Olympus Series
E-Star®
Mini-Split System
Service Manual
MODELS:
Read this manual carefully before installation and keep it where
the operator can easily nd it for future reference.
Due to updates and constantly improving performance, the
information and instructions within this manual are subject to
change without notice.
Version Date: April 20, 2026
Please visit www.mrcool.com/documentation
to ensure you have the latest version of this manual.
O-*-HP-WMAH-230C-O
O-ES-*-HP-C-230C-O1
This product utilizes R-454B refrigerant
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CONTENTS
SAFETY ............................................................................................................................... 2
SPECIFICATIONS ............................................................................................................... 9
2.1 Model Reference .................................................................................................. 9
2.2 External Appearance ........................................................................................... 9
2.3 Dimensional Drawing ........................................................................................ 10
2.4 Install Location .................................................................................................. 13
2.5 Line Set Height Dierence ................................................................................ 13
2.6 Noise Curves ...................................................................................................... 15
2.7 Refrigerant Cycle Diagrams .............................................................................. 17
2.8 Electrical Wiring Diagrams ............................................................................... 20
INSTALLATION ................................................................................................................ 26
3.1 Accessories ......................................................................................................... 26
3.2 Location Selection ............................................................................................. 26
3.3 Outdoor Unit Installation ................................................................................. 27
3.4 Refrigerant Pipe Installation ............................................................................ 27
3.5 Additional Refrigerant Charge ......................................................................... 29
3.6 Insulation ............................................................................................................ 29
3.7 Electrical Wiring ................................................................................................. 30
3.8 Test Operation ................................................................................................... 31
BASIC FUNCTION ............................................................................................................ 31
4.1 Abbreviation ....................................................................................................... 31
TROUBLESHOOTING ...................................................................................................... 33
5.1 Safety Caution .................................................................................................... 33
5.2 Error Display....................................................................................................... 34
5.3 Outdoor Unit Point Check Function ................................................................ 35
5.4 Quick Maintenance by Error Code .................................................................. 37
5.5 Troubleshooting by Error Code ....................................................................... 40
5.6 Check Procedures .............................................................................................. 63
TEMPERATURE SENSOR RESISTANCE TABLE ............................................................... 67
SYSTEM PRESSURE TABLE .............................................................................................. 69
Contents
1
2
3
4
5
6
7
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SAFETY
1
Incorrect usage may cause serious damage or injury.
The symbols below are used throughout this manual to indicate instructions that should be
followed closely or actions that should be avoided to prevent death, injury, and/or property
damage.
Safety Precautions
CAUTION
Indicates the possibility of personal injury or loss of life.
Indicates the possibility of property damage or serious
consequences.
Read Before Using
WARNING
WARNING FOR PRODUCT INSTALLATION
INSTALLATION MUST BE PERFORMED BY AN AUTHORIZED DEALER OR SPECIALIST. DEFECTIVE
INSTALLATION CAN CAUSE WATER LEAKAGE, ELECTRICAL SHOCK, OR FIRE.
****ELECTRICAL WORK MUST BE COMPLETED BY A QUALIFIED ELECTRICAL TECHNICIAN****
DO NOT install the unit in a location that may be exposed to combustible gas leaks. If
combustiblegasaccumulatesaroundtheunit,itcouldcausere.
DO NOT turn on the power until the installation and all work has been completed.
1. Installation must be performed according to the installation instructions. Improper installation could cause
water leakage, electrical shock, or re.
2. Contact an authorized service technician for repair or maintenance of this unit.
3. This appliance must be installed in accordance with national wiring regulations.
4. Only use the included accessories, parts, and specied parts for installation. Using non-standard parts can
cause water leakage, electrical shock, re, and/or failure of the unit.
5. Install the unit in a rm location that can support the unit’s weight. If the location cannot support the unit’s
weight, or the installation is not done properly, the unit may drop and cause serious injury and damage.
6. Install the drainage piping according to the instructions in this manual. Improper drainage could cause
water damage to your home and/or property.
7. When moving or relocating the air conditioner, consult experienced service technicians for disconnection
and re-installation of the unit.
8. For detailed information of how to install the indoor and outdoor units to their respective supports, please
refer to the indoor unit installation and outdoor unit installation sections of this manual.
9. USB device access, replacement, and maintenance operations must be carried out by professional sta.
WARNING FOR CLEANING & MAINTENANCE
1. DO NOT clean the unit with excessive amounts of water.
2. DO NOT clean the unit with combustible cleaning agents, as these could cause deformation and/or re.
3. Turn o the device and disconnect the power before cleaning. Failure to do this could result in electrical
shock.
TAKE NOTE OF FUSE SPECIFICATIONS
• The unit’s circuit board (PCB) is designed with a fuse to provide over-current protection.
• The specications of the fuse are printed on the circuit board, examples of such are T5A/250VAC and
T10A/250VAC.
Note: Only a blast-proof ceramic fuse can be used.
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SAFETY
1
WARNING FOR PRODUCT USE
DO NOT insertngers,rods,orotherobjectsintotheairinletoroutlet.Thiscouldcauseinjury,
since the fan may be rotating at high speeds.
DO NOT useammablesprayssuchashairspray,lacquerorpaintneartheunit,asthiscould
causereand/oranexplosion.
DO NOT operate the unit in places near or around combustible gases. Emitted gas may collect
around the unit and cause an explosion.
DO NOT allow children to play with the appliance. Children must be supervised around
the unit at all times.
DO NOT operate the unit in a room where it could be exposed to excessive amounts of water,
such as a bathroom or laundry room. Exposure to excessive water amounts can cause the
electrical components to short circuit.
DO NOT exposeyourbodydirectlytodirectcoolairowfromtheunitforaprolongedperiod
of time.
1. If the unit operates abnormally (emits strange noises or a burning smell), immediately turn o the unit
and disconnect the power in order to avoid electric shock, re, and/or injury. Call your local dealer, or
MRCOOL® tech support at (270) 366-0457, for further assistance.
2. If the air conditioner is used together with burners or other heating devices, thoroughly ventilate the room
in order to avoid an oxygen deciency.
3. In certain functional environments (such as kitchens and server rooms etc.), the use of specially designed
air-conditioning units is highly recommended.
4. This appliance is not intended for use by persons(including children) with reduced physical, sensory or
mental capabilities, or lack of experience and knowledge, unless they have been given supervision or
instruction concerning use of the appliance by a person responsible for their safety. Children should be
supervised to ensure that they do not play with the appliance.
5. Turn o the unit and disconnect the power before performing any cleaning, installation, or repairing.
Failure to do so can cause electric shock.
ELECTRICAL WARNINGS
****ELECTRICAL WORK MUST BE COMPLETED BY A QUALIFIED ELECTRICAL TECHNICIAN****
DO NOT sharethepowersupplywithotherappliances.Animproperorinsucientpower
supplycouldcausereand/orelectricalshock.
1. Only use the specied wire. If the wire is damaged, it must be replaced by the manufacturer, its service
agent or similarly qualied persons in order to avoid a hazard.
2. The product must be properly grounded during installation or electrical shock could occur.
3. Appropriate wiring standards, regulations, and the installation manual must be followed for all electrical
work.
4. If connecting power to xed wiring, an all-pole disconnection device must be incorporated in the xed
wiring in accordance with the wiring rules and must meet the following requirements: at least 3 mm of
clearances in all poles, a leakage current that may exceed 10 mA, and a residual current device (RCD)
having a rated residual operating current not exceeding 30 mA.
5. Connect cables tightly and clamp them securely to prevent external forces from damaging the terminal.
CAUTION
DO NOT allow the air conditioner to operate for extended periods of time with the doors or
windows open, or in very high humidity.
DO NOT operate the air conditioner with wet hands, as this could cause electric shock.
DO NOT use device for any other purpose than its intended use.
DO NOT climbontoorplaceobjectsontopoftheoutdoorunit.
1. Make sure that water condensation can drain smoothly and unhindered from the unit.
2. Turn o the unit and disconnect the power if the unit will not be used for an extended period of time.
3. Turn o and unplug the unit during storms.
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4
SAFETY
1
FLAMMABLE REFRIGERANT WARNINGS
1. The installation of pipe-work should be kept to a minimum and should be protected from physical damage.
2. Refrigerant pipes should comply with national gas regulations.
3. All mechanical connections and ventilation openings should be kept clear of obstruction.
4. Utilize proper disposal processes based on national regulations.
5. Any person involved with working on or breaking into a refrigerant circuit should hold a current valid
certicate from an industry-accredited assessment authority, which authorizes their competence to handle
refrigerants safely in accordance with an industry recognized assessment specication.
6. Maintenance and repair requiring the assistance of other skilled personnel shall be carried out under the
supervision of the person competent in the use of ammable refrigerants.
7. Do not use any means to accelerate the defrosting process or to clean, other than those recommended by
the manufacturer.
8. The appliance shall be stored in a room without continuously operating ignition sources (for example: open
ames, an operating gas appliance, or an operating electric heater).
9. Do not allow foreign matter (oil, water, etc.) to enter the piping, and securely seal the opening by pinching,
taping, etc.
10. Do not pierce or burn.
11. Refrigerants may not contain an odor.
12. Working procedures that aect safety should only be carried out by competent persons.
13. The unit should be stored in a well-ventilated area where the room size corresponds to the room area as
specic for operation, and should be stored so as to prevent potential mechanical damage from occurring.
14. Joints should be tested with detection equipment with a capability of 5 g/year of refrigerant or better, with
the equipment in standstill and under operation or under a pressure of at least these standstill or operation
conditions after installation. Detachable joints should NOT be used in the indoor side of the unit (brazed,
welded joint could be used).
15. A leak detection system is installed. The unit must be powered except for service. For units with a refrigerant
sensor, the indoor unit will display an error code and emit a buzzing sound, the compressor of the outdoor
unit will immediately stop, and the indoor fan will start running. The service life of the refrigerant sensor
is 15 years. When the refrigerant sensor malfunctions, the indoor unit will display the error code "FHCC".
The refrigerant sensor cannot be repaired and can only be replaced by the manufacturer. It should only be
replaced with the sensor specied by the manufacturer.
16. When a ammable refrigerant is used, the requirements for installation space of the appliance and/or
ventilation requirements are determined according to:
• The mass charge amount (M) used in the unit.
• The installation location.
• The type of ventilation of the location of the unit.
• Piping material, pipe routing, and installation must include protection from physical damage in
operation and service. This must be in compliance with local codes and standards, such as ASHRAE
15, IAPMO Uniform Mechanical Code, ICC International Mechanical Code, or CSA B52. All eld joints
must be accessible for inspection prior to being covered or enclosed.
• Protection devices, piping and ttings must be protected as much as possible against adverse
environmental eects. For example, against the danger of water collecting and freezing in relief pipes
or against accumulation of dirt or debris.
ELECTRICAL WARNINGS
Improper electrical connections could overheat, causing re and/or electrical shock.
5. All electrical connections must be made according to the Electrical Connection Diagram located on the
panels of the indoor and outdoor units.
6. All wiring must be properly arranged to ensure that the control board cover can close properly. If the
control board cover is not properly closed, it can lead to corrosion and cause the connection points on the
terminal to heat up, catch re, or cause electrical shock.
7. Disconnection must be incorporated in the xed wiring in accordance with the wiring rules.
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SAFETY
1
FLAMMABLE REFRIGERANT WARNINGS
• Piping in refrigeration systems must be designed and installed to minimize the likelihood of hydraulic
shock, resulting in damage from the system.
• Steel pipes and components must be protected against corrosion with a rust-proof coating before
applying insulation.
• Precautions must be taken against excessive vibration or movement of the unit.
• The minimum oor area of the room must be mentioned in the form of a table or a single gure
without reference to a formula.
17. After completion of eld piping for split systems, the eld pipework should be pressure tested with an inert
gas and then vacuum tested prior to refrigerant charging, according to the following requirements:
• The minimum test pressure for the low side of the system should be the low side design pressure and
the minimum test pressure for the high side of the system should be the high side design pressure,
unless the high side of the system cannot be isolated from the low side of the system in which case the
entire system should not be pressure tested to the low side design pressure.
• The test pressure after removal of pressure source shall be maintained for at least 1 hour with no
decrease of pressure indicated by the test gauge, with test gauge resolution not exceeding 5% of the
test pressure.
18. Prior to beginning work on systems containing ammable refrigerants, safety checks are necessary
to ensure that the risk of ignition is minimized. For repairs to the refrigerating system, the following
precautions shall be complied with prior to conducting work on the system.
19. Work should be undertaken under a controlled procedure so as to minimize the risk of a ammable gas or
vapor being present while the work is being performed.
20. All maintenance sta and others working in the local area should be instructed on the nature of work being
carried out. Avoid work in conned spaces.
21. The area should be checked with an appropriate refrigerant detector prior to and during work, to ensure the
technician is aware of potentially ammable atmospheres. Ensure that the leak detection equipment being
used is suitable for use with ammable refrigerants, i.e. no sparking, adequately sealed, or intrinsically safe.
22. If any hot work is to be conducted on the refrigeration equipment or any associated parts, appropriate re
extinguishing equipment should be on site and readily available. Have a dry power or CO2 re extinguisher
adjacent to the charging area.
23. No person carrying out work in relation to a refrigerating system which involves exposing any pipe work
should use any sources of ignition in such a manner that it may lead to the risk of re or explosion. All
possible ignition sources, including cigarette smoking, should be kept suciently far away from the site
of installation, repairing, removing, and disposal, during which refrigerant can possibly be released to the
surrounding space. Prior to work taking place, the area around the equipment is to be surveyed to make
sure that there are no ammable hazards or ignition risks. "No Smoking" signs should be displayed.
24. Ensure that the area is in the open or that it is adequately ventilated before breaking into the system or
conducting any hot work. A degree of ventilation shall continue during the period that the work is carried
out. The ventilation should safely disperse any released refrigerant and preferably expel it externally into the
atmosphere.
23. Where electrical components are being changed, they shall be t for the purpose and to the correct
specication. At all times the manufacturer's maintenance ad service guidelines shall be followed. If in
doubt, consult the manufacturer's technical department for assistance. The following checks should be
applied to installations using ammable refrigerants:
• the actual refrigerant charge is in accordance with the room size within which the refrigerant containing
parts are installed;
• the ventilation machinery and outlets are operating adequately and are not obstructed;
• if an indirect refrigerating circuit is being used, the secondary circuits should be checked for the
presence of refrigerant;
• marking to the equipment continues to be visible and legible, marking and signs that are illegible
should be corrected;
• refrigerant pipe or components are installed in a position where they are unlikely to be exposed to
any substance which may corrode refrigerant containing components, unless the components are
constructed of materials which are inherently resistant to or protected against corrosion.
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SAFETY
1
FLAMMABLE REFRIGERANT WARNINGS
24. Repair and maintenance to electrical components shall include initial safety checks and component
inspection procedures. If a fault exists that could compromise safety, then no electrical supply shall be
connected to the circuit until it is satisfactorily dealt with. If the fault cannot be corrected immediately but it
is necessary to continue operation, an adequate temporary solution should be used.
25. Initial safety checks should include:
• that capacitors are discharged: this should be done in a safe manner to avoid the possibility of sparking;
• that there are no live electrical components and wiring are exposed while charging, recovering, or
purging the system;
• that there is continuity of earth bonding.
26. Sealed electrical components should be replaced if damaged.
27. Intrinsically safe components should be replaced if damaged.
28. Check that wiring will not be subject to wear, corrosion, excessive pressure, vibration, sharp edges, or
any other adverse environmental eects. The check shall also take into account the eects of aging or
continual vibration from sources such as compressors or fans.
29. Under no circumstances should potential sources of ignition be used in the search for or detection of
refrigerant leaks. A halide torch (or any other detector using a naked ame) should not be used. The
following leak detection methods are deemed acceptable for refrigerant systems. Electronic leak detectors
may be used to detect refrigerant leaks but, in the case of ammable refrigerants, the sensitivity may
not be adequate, or may need re-calibration. (Detection equipment shall be calibrated in a refrigerant-
free area.) Ensure that the detector is not a potential source of ignition and is suitable for the refrigerant
used. Leak detection equipment shall be set at a percentage of the LFL of the refrigerant and should
be calibrated to the refrigerant employed, and the appropriate percentage of gas (25% minimum) is
conrmed. Leak detection uids are also suitable for use with most refrigerants but the use of detergents
containing chlorine may react with the refrigerant and corrode the copper work. Examples of leak
detection uids are the bubble method, uorescent method agents, etc. If a leak is suspected, all naked
ames should be removed/extinguished. If a leakage of refrigerant is found which requires brazing, all of
the refrigerant should be recovered from the system, or isolated (by means of shut-o valves) in a part of
the system remote from the leak. See the following instructions of removal of refrigerant.
30. When breaking into the refrigerant circuit to make repairs, or for any other purpose, conventional
procedures should be used. However, for ammable refrigerants, it is even more vital to follow best
practice. The following procedure should be adhered to:
• safely remove refrigerant following local and national regulations;
• evacuate;
• purge the circuit with inert gas;
• evacuate;
• continuously ush or purge with inert gas when using ame to open circuit;
• open the circuit
31. The refrigerant charge should be recovered into the correct recovery cylinders if venting is not allowed by
local and national codes. For units containing ammable refrigerants, the system should be purged with
oxygen-free nitrogen to render the appliance safe for ammable refrigerants. This process might need to
be repeated several times. Compressed air or oxygen shall not be used for purging refrigerant systems.
For appliances containing ammable refrigerants, refrigerant purging should be achieved by breaking the
vacuum in the system with oxygen-free nitrogen and continuing to ll the working pressure is achieved,
then venting to atmosphere, and nally pulling down to a vacuum. This process should be repeated until
no refrigerant is within the system. When the nal oxygen-free nitrogen charge is used, the system should
be vented down to atmospheric pressure to enable work to take place. The outlet for the vacuum pump
should not be close to any potential ignition sources, and ventilation should be available.
32. In addition to conventional charging procedures, the following requirements should be followed:
• Work should be undertaken with appropriate tools only (in case of uncertainty, please consult the
manufacturer of the tools for use with ammable refrigerants)
• Ensure that contamination of dierent refrigerants does not occur when using charging equipment.
Hoses or lines shall be as short as possible to minimize the amount of refrigerant contained in them.
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OVERVIEW
2
FLAMMABLE REFRIGERANT WARNINGS
• Ensure that the refrigeration system is grounded prior to charging the system with refrigerant.
• Label the system when charging is complete (if not already).
• Extreme care should be taken not to overll the refrigeration system.
• Prior to recharging the system, it should be pressure tested with oxygen-free nitrogen (OFN). The
system should be leak-tested on completion of charging but prior to commissioning. A follow-up leak
test shall be carried out prior to leaving the site.
33. Before carrying out this procedure, it is essential that the technician is completely familiar with the
equipment and all its detail. It is good recommended practice that all refrigerants are recovered safely.
Prior to the task being carried out, an oil and refrigerant sample should be taken in case analysis is
required prior to re-use of recovered refrigerant. It is essential that electrical power is available before the
task is commenced.
a. Become familiar with the equipment and its operation.
b. Isolate the system electrically.
c. Before attempting the procedure ensure that:
• mechanical handling equipment is available, if required, for handling refrigerant cylinders;
• all personal protective equipment is available and being used correctly;
• the recovery process is supervised at all times by a competent person;
• recovery equipment and cylinders conform to the appropriate standards
Pump down refrigerant system, if possible.
e. If a vacuum is not possible, make a manifold so that refrigerant can be removed from various parts of
the system.
f. Make sure that the cylinder is situated on the scales before recovery takes place.
g. Start the recovery machine and operate in accordance with instructions.
h. Do not overll cylinders (no more than 80% volume liquid charge).
i. Do not exceed the maximum working pressure of the cylinder, even temporarily.
j. When the cylinders have been lled correctly and the process completed, make sure that the cylinders
and equipment are removed from the site promptly and all isolation valves on the equipment are closed o.
k. Recovered refrigerant should not be charged into another refrigeration system unless it has been
cleaned and checked.
34. Equipment shall be labeled stating that it has been decommissioned and emptied of refrigerant. The label
should be dated and signed. For appliances containing ammable refrigerants, ensure that there are labels
on the equipment stating the equipment contains ammable refrigerant.
35. When removing refrigerant from a system, either for servicing or decommissioning, it is good
recommended practice that all refrigerants are removed safely. When transferring refrigerant into
cylinders, ensure that only appropriate refrigerant recovery cylinders are employed. Ensure that the
correct number of cylinders for holding the total system charge is available. All cylinders to be used should
be designated for the recovered refrigerant and labeled for that refrigerant (i.e. special cylinders for the
recovery of refrigerant). Cylinders shall be complete with pressure-relief valve and associated shut-o
valves in good working order. Empty recovery cylinders are evacuated and, if possible, cooled before
recovery occurs. The recovery equipment should be in good working order with a set of instructions
concerning the equipment that is at hand and should be suitable for the recovery of the ammable
refrigerant. If in doubt, the manufacturer should be consulted. In addition, a set of calibrated weighing
scales should be available and in good working order. Hoses should be complete with leak-free disconnect
couplings and in good condition. The recovered refrigerant should be processed according to local
legislation in the correct recovery cylinder, and the relevant waste transfer note arranged. Do not mix
refrigerants in recovery units and especially not in cylinders.
36. If compressors or compressor oils are to be removed, ensure that they have been evacuated to an
acceptable level to make certain that ammable refrigerant does not remain within the lubricant. The
compressor body should not be heated by an open ame or other ignition sources to accelerate this
process. When oil is drained from a system, it should be carried out safely.
37. An unventilated area where the appliance using ammable refrigerants is installed should be constructed
so that should any refrigerant leak, it will not stagnate so as to create a re or explosion hazard. If
appliances connected via an air duct system to one or more rooms below the ventilation requirements,
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SPECIFICATIONS
3
FLAMMABLE REFRIGERANT WARNINGS
that room should never contain potential ignition sources. A ame-producing device may be installed
in the space if the device is provided with an eective ame arrest. Auxiliary devices which may be a
potential ignition source should not be installed in the duct work. Examples of such are hot surfaces with
a temperature exceeding 1292°F (700°C) and electric switching devices. Only auxiliary devices (such as
a certied heater kit) approved by the manufacturer or declared suitable with the refrigerant should be
installed in connecting ductwork. False or drop ceilings may be used as a return air plenum if a refrigerant
detection system is provided in the appliance and any external connections are also provided with a sensor
immediately below the return air plenum duct joint. Refrigerant sensors for refrigerant detection systems
should only be replaced with sensors specied by the manufacturer. A leak detection system is installed.
The unit must be powered except for service.
38. Transport of equipment containing ammable refrigerants should comply with transportation regulations.
39. Marking of equipment using signs should comply with local regulations.
40. Disposal of equipment using ammable refrigerants should comply with national regulations.
41. Storage of equipment/appliances should be in accordance with the manufacturer's instructions.
42. Storage of packed (unsold) equipment should be constructed so that mechanical damage to the equipment
inside the package will not cause a leak of the refrigerant charge. The maximum number of pieces of
equipment permitted to be stored together will be determined by local regulations.
43. During the evacuation test, after achieving a vacuum level specied in the manual or less, the refrigeration
system shall be isolated from the vacuum pump and the pressure shall not rise above 1500 microns within
10 minutes. The vacuum pressure level should be specied in the manual, and should be the lessor of 500
microns of the value required for compliance with national and local codes and standards, which may vary
between residential, commercial, and industrial buildings.
• Field-made refrigerant joints indoors should be tightness-tested according to the following
requirements: the test method should have a sensitivity of 5 grams per year of refrigerant or better
under a pressure of at least 0.25 times the maximum allowable pressure. No leak should be detected.
• Any servicing should be performed only as recommended by MRCOOL®.
43. Any maintenance, service, or repair operations must be performed by qualied personnel. Every working
procedure that aects safety should only be carried out by competent persons that are both trained and
certied. The training of these procedures should be carried out by national training organizations or
manufacturers that are accredited to teach the relevant national competency standards that may be set in
legislation. All training should follow the ANNEX HH requirements of UL 60334-2-40 4th Edition.
Examples of such working procedures are:
• breaking into a refrigerant circuit
• opening of sealed components
• opening of ventilated enclosures
Symbols Displayed on Indoor & Outdoor Unit
WARNING
This symbol shows that this appliance uses a ammable refrigerant. If the refrigerant
is leaked and exposed to an external ignition source, there is a risk of re.
CAUTION This symbol shows that the operation manual should be read carefully.
CAUTION
This symbol shows that a service personnel should be handling this equipment with
reference to the installation manual.
CAUTION
CAUTION
This symbol shows that information is available such as the operating manual or
installation manual.
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SPECIFICATIONS
2
2.1 Model Reference
Outdoor Unit Model Capacity(Btu/h) Power Supply
O-ES-09-HP-C-230C-O1 9K
1Ph, 208/230V~, 60Hz
O-ES-12-HP-C-230C-O1 12K
O-ES-18-HP-C-230C-O1 18K
O-ES-24-HP-C-230C-O1 24K
2.2 External Appearance
9/12K
18K
24K
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SPECIFICATIONS
2
2.3 Dimensional Drawing
Please check the corresponding dimensional drawing according to the panel plate.
Outdoor Unit Model Panel Plate
O-ES-09-HP-C-230C-O1 X230
O-ES-12-HP-C-230C-O1 X230
O-ES-18-HP-C-230C-O1 X430
O-ES-24-HP-C-230C-O1 D30
X230 Platform
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SPECIFICATIONS
2
X430 Platform
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SPECIFICATIONS
2
D30 Platform
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SPECIFICATIONS
2
2.4 Install Location
2.5LineSetHeightDierence
Capacity(Btu/h) 9K PipeLength(ft/m)
Cooling 24.6/7.5 32.8/10 65.6/20 82/25
Height Dierence H
(ft/m)
Indoor Higher
Than Outdoor
15/49.2 0.975 0.911
32.8/10 0.985 0.985 0.920
16.4/5 0.995 0.995 0.995 0.929
0 1.000 1.000 1.000 0.934
Outdoor Higher
Than Indoor
-16.4/-5 1.000 1.000 1.000 0.934
-32.8/-10 1.000 1.000 0.934
-15/-49.2 1.000 0.934
Heating 24.6/7.5 32.8/10 65.6/20 82/25
Height Dierence H
(ft/m)
Indoor Higher
Than Outdoor
15/49.2 1.000 0.956
32.8/10 1.000 1.000 0.956
16.4/5 1.000 1.000 1.000 0.956
0 1.000 1.000 1.000 0.956
Outdoor Higher
Than Indoor
-16.4/-5 0.992 0.992 0.992 0.948
-32.8/-10 0.984 0.984 0.941
-15/-49.2 0.976 0.933
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SPECIFICATIONS
2
Capacity(Btu/h) 12K PipeLength(ft/m)
Cooling 24.6/7.5 32.8/10 65.6/20 82/25
Height Dierence H
(ft/m)
Indoor Higher
Than Outdoor
15/49.2 0.975 0.932
32.8/10 0.985 0.985 0.942
16.4/5 0.995 0.995 0.995 0.951
0 1.000 1.000 1.000 0.956
Outdoor Higher
Than Indoor
-16.4/-5 1.000 1.000 1.000 0.956
-32.8/-10 1.000 1.000 0.956
-15/-49.2 1.000 0.956
Heating 24.6/7.5 32.8/10 65.6/20 82/25
Height Dierence H
(ft/m)
Indoor Higher
Than Outdoor
15/49.2 0.981 0.974
32.8/10 0.994 0.981 0.974
16.4/5 1.000 0.994 0.981 0.974
0 1.000 0.994 0.981 0.974
Outdoor Higher
Than Indoor
-16.4/-5 0.992 0.986 0.973 0.966
-32.8/-10 0.978 0.965 0.958
-15/-49.2 0.957 0.951
Capacity(Btu/h) 18K PipeLength(ft/m)
Cooling 24.6/7.5 32.8/10 65.6/20 98.4/30
Height Dierence H
(ft/m)
Indoor Higher
Than Outdoor
65.6/20 0.941 0.919
32.8/10 0.974 0.951 0.928
16.4/5 0.995 0.983 0.960 0.937
0 1.000 0.988 0.965 0.942
Outdoor Higher
Than Indoor
-16.4/-5 1.000 0.988 0.965 0.942
-32.8/-10 0.988 0.965 0.942
-65.6/-20 0.965 0.942
Heating 24.6/7.5 32.8/10 65.6/20 98.4/30
Height Dierence H
(ft/m)
Indoor Higher
Than Outdoor
65.6/20 0.987 0.978
32.8/10 0.996 0.987 0.978
16.4/5 1.000 0.996 0.987 0.987
0 1.000 0.996 0.987 0.978
Outdoor Higher
Than Indoor
-16.4/-5 0.992 0.988 0.979 0.970
-32.8/-10 0.980 0.971 0.962
-65.6/-20 0.963 0.955
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SPECIFICATIONS
2
Capacity
(Btu/h)
24K PipeLength(ft/m)
Cooling 24.6/7.5 32.8/10 65.6/20 98.4/30 131.20/40 164/50
Height
Dierence H
(ft/m)
Indoor
Higher Than
Outdoor
82/25 0.917 0.898 0.879
65.6/20 0.946 0.926 0.907 0.887
32.8/10 0.975 0.955 0.936 0.916 0.896
16.4/5 0.995 0.985 0.965 0.945 0.925 0.905
0 1.000 0.990 0.970 0.950 0.930 0.910
Outdoor
Higher Than
Indoor
-16.4/-5 1.000 0.990 0.970 0.950 0.930 0.910
-32.8/-10 0.990 0.970 0.950 0.930 0.910
-65.6/-20 0.970 0.950 0.930 0.910
-82/-25 0.950 0.930 0.910
Heating 24.6/7.5 32.8/10 65.6/20 98.4/30 131.2/40 164/50
Height
Dierence H
(ft/m)
Indoor
Higher Than
Outdoor
82/25 0.984 0.978 0.972
65.6/20 0.991 0.984 0.978 0.972
32.8/10 0.997 0.991 0.984 0.978 0.972
16.4/5 1.000 0.997 0.991 0.984 0.978 0.972
0 1.000 0.997 0.991 0.984 0.978 0.972
Outdoor
Higher Than
Indoor
-16.4/-5 0.992 0.989 0.983 0.977 0.970 0.964
-32.8/-10 0.981 0.975 0.969 0.963 0.957
-65.6/-20 0.967 0.961 0.955 0.949
-82/-25 0.953 0.947 0.941
2.6 Noise Curves
Notes:
-Sound is measured at 3.25ft/1.0m away from the
center of the unit.
-Data is valid at free eld condition.
-Data is valid at nominal operation condition.
-Reference acoustic pressure 0db=20µPa.
-The sound level will vary depending on arrange
off factors as the construction (acoustic absorption
coefficient) of the room in which the equipment is
installed.
-The operating conditions are assumed to be
standard.
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16
SPECIFICATIONS
2
O-ES-09-HP-C-230C-O1 O-ES-12-HP-C-230C-O1
O-ES-18-HP-C-230C-O1 O-ES-24-HP-C-230C-O1
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SPECIFICATIONS
2
2.7 Refrigerant Cycle Diagrams
Compressor
Model No.
Pipe Size
(Diameter:Ø)
inch(mm)
Piping Length
(ft/m)
Elevation(ft/m)
Additional
Refrigerant
Gas Liquid Rated Max. Rated Max
O-ES-09-HP-C-230C-O1
3/8(9.52) 1/4(6.35) 24.6/7.5 82/25 0 49.2/15 0.16oz/ft (15g/m)
O-ES-12-HP-C-230C-O1
Condenser
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18
SPECIFICATIONS
2
Condenser
Model No.
Pipe Size
(Diameter:Ø)
inch(mm)
Piping Length
(ft/m)
Elevation(ft/m)
Additional
Refrigerant
Gas Liquid Rated Max. Rated Max
O-ES-18-HP-C-230C-O1 1/2(12.7) 1/4(6.35) 24.6/7.5 98.4/30 0 65.6/20 0.16oz/ft (15g/m)
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SPECIFICATIONS
2
Condenser
Model No.
Pipe Size
(Diameter:Ø)
inch(mm)
Piping Length
(ft/m)
Elevation(ft/m)
Additional
Refrigerant
Gas Liquid Rated Max. Rated Max
O-ES-24-HP-C-230C-O1 5/8(16) 3/8(9.52) 24.6/7.5 164/50 0 82/25 0.32oz/ft (30g/m)
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20
SPECIFICATIONS
2
2.8 Electrical Wiring Diagrams
ODU Model ODU Wiring Diagram ODU Main Printed Circuit Board
O-ES-09-HP-C-230C-O1
16022000040311 17122000057661
O-ES-12-HP-C-230C-O1
O-ES-18-HP-C-230C-O1
16022000040313
17122000048066
O-ES-24-HP-C-230C-O1
17122000048064
Outdoor Unit Wiring Diagram: 16022000040311
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SPECIFICATIONS
2
Outdoor Unit Wiring Diagram: 16022000040313
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SPECIFICATIONS
2
Outdoor Unit Wiring Diagram: 17122000057661
mrcool.com23
No. Name NC# Meaning
1 TESTPORT NC6 Used for testing
2 PMV CN31 Connects to electric expansion valve (Output: 0~20VDC)
3 DC-FAN CN7 Connects to DC fan (Output: 0~310VAC)
4 TP T4 T3 CN31
Connects to pipe temp. sensor T3, Ambient Temp.
sensor T4, exhaust temp. sensor TP (Output: 0~5VDC)
5 HEAT1 CN17 Connects to compressor heater (Output: 230VAC)
6 4-WAY CN60 Connects to 4 way valve (Output: 230VAC)
7 HEAT2 CN15 Connects to chassis heater (Output: 230VAC)
8 CN1A
CN16 S: Connects to indoor unit communication
CN2 L_in: Connects to L-line (230VAC input)
CN1 N_in: Connects to N-line (230VAC input)
CN3 Earth
9 CN50
W
Connects to compressor (Output: 0~310VAC)V
U
Note: This section is for reference only. Please take practicality as standard.
SPECIFICATIONS
2
mrcool.com 24
24
Outdoor Unit Wiring Diagram: 17122000048064 & 17122000048066
SPECIFICATIONS
2
mrcool.com25
No. Name NC# Meaning
1 Power Supply
CN6 Earth: Connects to ground
CN7 N_in: Connects to N-line (230VAC input)
CN8 L_in: Connects to L-line (230VAC input)
2 S CN2
S; Connects to indoor unit communication (230VAC
input)
3 4-WAY CN60 Connects to 4 way valve (Output: 230VAC)
4 AC-FAN CN5 Connects to AC fan
5 HEAT2 CN18 Connects to chassis heater (Output: 230VAC)
6 TP T4 T3 CN17
Connects to pipe temp. sensor T3, ambient temp.
sensor T4, exhaust temp. sensor TP (Output: 0~5VDC)
7 PMV CN18 Connects to electric expansion valve
8 HEAT1 CN16 Connects to compressor heater (Output: 230VAC)
9 DC-FAN CN414 Connects to DC fan (Output: 230VAC)
10 TESTPORT CN23 Used for testing
11 FAN_IPM IPM501 IPM for DC fan
12 COMP_IPM IPM1 IPM for compressor
13
U CN27
Connects to compressor (Output: 0~310VAC)V CN28
W CN29
14 EE_PORT CN505 EEPROM programmer port
Note: This section is for reference only. Please take practicality as standard.
SPECIFICATIONS
2
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26
INSTALLATION
3
3.1 Accessories
Name Shape Quantity
Drain Joint
1
Seal
1
3.2 Location Selection
-For unit location selection refer to the installation manual.
DO NOT install the unit in the following locations:
• Near an obstacle that will block air inlets and
outlets.
• Near a public street, crowded areas, or where
noise from the unit will disturb others.
• Near animals or plants that will be harmed by hot
air discharge.
• Near any source of combustible gas.
• In a location that is exposed to large amounts of
dust.
• In a location exposed to excessive amounts of
salty air.
MeetallrequirementsshownintheInstallation
ClearanceRequirementsbelow.
Rows of Series Installation:
L A
L≤H
L≤1/2H 9.8in (25cm) or more
1/2H<L≤H 11.8in (30cm) or more
L>H
Cannot be installed
Note:
H: Unit Height
L: Height of the wall behind the unit
A: Distance between the unit and the wall
If the unit is exposed to heavy wind:
• Install the unit so that the air outlet fan is at a 90°
angle to the direction of the wind. If needed, build
a barrier in front of the unit to protect it from
extremely heavy winds.
Iftheunitisfrequentlyexposedtoheavyrainor
snow:
• Build a shelter above the unit to protect it from
the rain or snow. Be careful not to obstruct air
ow around the unit.
Iftheunitisfrequentlyexposedtosaltyair
(seaside):
• Use an outdoor unit that is specially designed to
resist corrosion.
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INSTALLATION
3
3.3 Outdoor Unit Installation
Installation of Drain Joint:
Before bolting the outdoor unit in place, you must
install the drain joint at the bottom of the unit.
Note that there are two dierent types of drain joints
depending on the type of outdoor unit.
If the drain joint comes with a rubber seal (see Fig. A),
do the following:
1. Fit the rubber seal on the end of the drain joint
that will connect to the outdoor unit.
2. Insert the drain joint into the hole in the base pan
of the unit.
3. Rotate the drain joint 90° until it clicks in place
facing the front of the unit. For some panel plates,
you need to use a tool.
4. Connect a drain hose extension (not included)
to the drain joint to redirect water from the unit
during heating mode.
If the drain joint doesn't come with a rubber seal (see
Fig. B), do the following:
1. Insert the drain joint into the hole in the base pan
of the unit. The drain joint will click into place.
2. Connect a drain hose extension (not included)
to the drain joint to redirect water from the unit
during heating mode.
Anchor Outdoor Unit:
The outdoor unit can be anchored to the ground or
to a wall-mounted bracket with bolt (M10). Prepare
the installation base of the unit according to the
dimensions in the next column.
The following is a list of dierent outdoor unit sizes
and the distance between their mounting feet.
Panel Plate Unit D A B C
X2
inch 11.93 17.80 11.26 12.36
mm 303 452 286 314
X4
inch 13.46 26.1 13.94 15.5
mm 642 663 354 394
D30
inch 16.14 26.50 15.87 17.9
mm 410 673 403 455
3.4 Refrigerant Pipe Installation
Maximum Length and Drop Height:
Ensure that the length of the refrigerant pipe, the
number of bends, and the drop height between the
indoor and the outdoor units meet the requirements
shown in the following table.
Capacity(kBtu/h) Max.Length(ft/m) Max. Elevation
(ft/m)
9/12K 82/25 49.2/15
18K 98.4/30 65.6/20
24 164/50 82/25
Current Loop
CAUTION
1. The capacity test is based on the standard length
and the maximum permissive length is based on
the system reliability.
2. Oil traps
• If oil ows back into the outdoor unit's
compressor, this might cause liquid compression
or deterioration of oil return. Oil traps in the
rising gas piping can prevent this.
• An oil trap should be installed every 20ft(6m) of
vertical suction line riser (<36KBtu/h unit).
• An oil trap should be installed every 32.8ft(10m)
of vertical suction line riser (≥36KBtu/h unit).
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28
Procedure of Connecting Pipes:
1. Choose the pipe size according to the specication
table.
2. Conrm the cross way of the pipes.
3. Measure the necessary pipe length.
4. Cut the selected pipe with a pipe cutter.
• Make the section at and smooth.
5. Insulate the copper pipe.
• Before test operation, the joint parts should not
be heat insulated.
6. Flare the pipe.
• Insert a are nut into the pipe before aring the
pipe according to the following table.
Pipe Diameter
(inch(mm))
Flare Dimension A
Flare Shape
Min. Max.
Ø1/4 (Ø6.35) 0.33/8.4 0.34/8.7
Ø3/8(Ø9.52) 0.52/13.2 0.53/13.5
Ø1/2(Ø12.7) 0.64/16.2 0.65/16.5
Ø5/8(Ø15.9) 0.76/19.2 0.78/19.7
Ø3/4(Ø19) 0.91/23.2 0.93/23.7
Ø7/8(Ø22) 1.04/26.4 1.06/26.9
• After aring the pipe, the opening end must be
sealed to avoid dust or impurities from coming
into the piping.
7. Drill holes if the pipes need to pass through the
wall.
8. If needed bend the pipes slowly to pass through
the wall.
9. Bind and wrap the wire together with the
insulated pipes if necessary.
10. Set the wall conduit.
11. Set the supporter for the pipe.
12. Locate the pipe and x it by the supporter.
• For horizontal refrigerant pipe, the distance
between supporters should not exceed 3.2ft
(1m).
• For vertical refrigerant pipe, the distance
between supports should not exceed 4.9ft
(1.5m).
13. Connect the pipe to the indoor and outdoor unit
by using two crescent wrenches.
• Be sure to use two crescent wrenches and
proper torque to fasten the nut, too much
torque will damage the bell housing, and too
little of torque can cause leakage. Refer to the
following table for dierent pipe connections.
Pipe Diameter
(inch(mm))
Torque
Flare Shape
N.m(lb.ft)
Ø1/4 (Ø6.35)
18~20
(13.3~14.8)
Ø3/8(Ø9.52)
32~39
(23.6~28.8)
Ø1/2(Ø12.7)
49~59
(36.1~43.5)
Ø5/8(Ø15.9)
57~71
(42~52.4)
Ø3/4(Ø19)
67~101
(49.4~74.5)
Ø7/8(Ø22)
85~110
(62.7~81.1)
3.4 Vacuum Drying & Leak Checks
The Purpose of Vacuum Drying:
• Eliminating moisture in the system to prevent the
formation of ice-blockage and copper oxidation
which can damage the compressor.
• Eliminating non-condensible gas (air) in the system
prevents the components from oxidizing, pressure
uctuation, and poor heat exchange during the
operation of the system.
Selection of a Vacuum Pump:
• The maximum vacuum degree of a pump shall be
-756mmHg or above.
• Precision of a vacuum pump shall reach
0.02mmHg or above.
INSTALLATION
3
mrcool.com29
Operation Procedure for Evacuation:
• Due to dierent construction environments
two ways of evacuation can be done, ordinary
evacuation and special evacuation.
Ordinary Evacuation:
• When conducting the rst evacuation, connect
your gauges to the gas and liquid pipe and run
the vacuum pump for 1 hour (the degree of the
vacuum pump shall be reached -755mmHg).
• If the vacuum degree could not reach -755mmHg
after 1 hour of running, it indicates that there is
moisture or leakage in the pipeline of the system
and needs to run for an additional half hour.
• If the vacuum degree still could not reach
-755mmHg after and hour and a half of running,
check to see if there is a leak in the system.
• Leakage test: After the vacuum degree reaches
-755mmHg, stop the pump and let it set for an
hour. If the indicator of the vacuum gauge does
not go up it is sealed. If the gauge goes up it
indicates there is moisture in the system or a leak
source.
Special Evacuation:
Special evacuation should be used when:
1. Finding moisture when ushing the refrigerant
pipe.
2. Installation on a rainy day (as rain may have
entered the pipeline).
3. Installation period is long and rain water may have
entered the pipeline.
Procedures of special evacuation are as follows:
1. Vacuuming for one hour.
2. Stop the pump and ll with nitrogen to reach
0.5Kgf/cm
2
.
3. Vacuum again for half an hour.
If the pressure reached -775mmHg, start to pressure
leak test. If it cannot reach the value vacuum again for
1 hour.
4. Leakage test: After the vacuum degree reaches
-755mmHg, stop the pump and let it set for an
hour. If the indicator of the vacuum gauge does
not go up it is sealed. If the gauge goes up it
indicates there is moisture in the system or a leak
source.
3.5 Additional Refrigerant Charge
After the vacuuming process is carried out, the
additional refrigerant charge process needs to be
performed.
The outdoor unit is factory charged with refrigerant.
The additional refrigerant charge volume is decided
by the diameter and length of the liquid pipe between
the indoor and outdoor unit. Refer to the next column
for the formula to calculate the charge volume.
DiameterofLiquid
Pipe(inch(mm))
Formula
R454B
Ø1/4(Ø6.35)
V=0.16(15)oz/
ft(g/m)x(L-standard
pipe length)
Ø3/8(Ø9.52)
V=0.32(30)oz/
ft(g/m)x(L-Standard
pipe length)
V: Additional refrigerant charge volume
L: The length of the liquid pipe
NOTE
• Refrigerant may only be added after vacuuming.
• Always use gloves and safety glasses to protect
your hands and eyes during charging.
• Use an electronic scale or uid infusion
apparatus to weigh in refrigerant. Be sure
to avoid overcharging as it can cause liquid
hammering of the compressor.
• Charge the system in a liquid state.
• Before recharging the air in your gauges and
lines should be purged.
• After charging check for leaks at joints using an
leak detector or soapy water.
3.6 Insulation
Insulation of Refrigerant Pipe:
Cut the pipe—insulation (except joint section)—are
the pipe—piping layout and connection—vacuum—
insulate the joining parts
Purpose of Refrigerant Pipe Insulation:
• During operation the temperature of the gas pipe
and liquid pipe will be hot/cold. Therefore, it is
necessary to install insulation; otherwise it will
lower performance or burn up the compressor.
• The gas pipe temperature is low during cooling.
If there is insucient insulation it will condensate
and drip.
• The temperature of the gas pipe is high
(122°F~212°F(50°C~100°C) during heating.
Insulation must be installed to prevent burns.
Insulation Material Selection for Refrigerant Pipe:
• The insulation rating should be over 248°F (120°C).
• Choose insulation according to local codes and
ordnances.
• The thickness of the insulation should be above
0.39in(10mm). If in a hot or wet environment use
thicker insulation.
Installation Highlights:
• The gas and liquid pipe should be insulated
separately, if the gas pipe and liquid pipe
were insulated together it will decrease the
performance of the system.
INSTALLATION
3
mrcool.com 30
• The insulation material at the joint pipe should be
1.96in~3.93in(5cm~10cm) longer than the gap of
insulation material.
• The insulation material at the joint pipe should be
inserted into the gap of the insulation material.
• The insulation material at the joint pipe should be
banded to the gap pipe and liquid pipe tightly.
• The a joining part should be glued together.
• Be sure not to bind the insulating material over-
tight, it may extrude out the air in the material and
cause it to rot.
3.7 Electrical Wiring
Highlights of Electrical Wiring Installation:
• All wiring must comply with local and national
electrical codes, regulations, and must be installed
by a licensed electrician.
• All electrical connections must be made according
to the Electrical Connection Diagram located on
the panels of the indoor and outdoor unit.
• If there is a serious safety issue with the power
supply, stop work immediately. Explain your
reasoning to the client, and refuse to install the
unit until the safety issue is properly resolved.
• Power voltage should be within 90~110% of the
rated voltage. Insucient power supply can cause
malfunction, electrical shock, or re.
• Installation of an external surge suppressor at the
outdoor disconnect is recommended.
• If connecting power to xed wiring, a switch or
circuit breaker that disconnects all poles and has
a contact separation of at least 1/8in(3mm) must
be incorporated in the xed wiring. The qualied
technician must use an approved circuit breaker
or switch.
• Only connect the unit to an individual branch
circuit. Do not connect another appliance to that
outlet.
• Make sure to properly ground the air conditioner.
• Every wire must be rmly connected. Loose wiring
can cause the terminal to overheat, resulting in
product malfunction and possible re.
• Do not let wires touch or rest against refrigerant
tubing, the compressor, or any moving parts
within the unit.
• If the unit has an auxiliary electric heater, it must
be installed at least 40in(1m) away from any
combustible material.
• To avoid electrical shock, never touch the electrical
components after the power supply has been
turned o. After turning o the power, always
wait 10 minutes or more before you touch the
electrical components.
• Make sure that you do not cross your electrical
wiring with your signal wiring as this may cause
distortion, interference, or possibly damage to the
circuit boards.
• No other equipment should be connected to the
same power circuit.
• Connect the outdoor wires before connecting the
indoor wires.
Table: Minimum Cross-Sectional Area of Power
and Signal Cables:
Rated Current of Appliance
(A)
AWG
≤6 18
6~10 16
10~16 14
16~25 12
25~32 10
Outdoor Unit Wiring:
Before performing any electrical work, turn o the
main power to the system.
1. Prepare the cable for connection.
a. You must rst choose the right cable size.
Choose the cable type according to the electrical
codes and regulations.
b. The size of the power supply cable, signal cable,
fuse, and switch needed is determined by the
Minimum Circuit Ampacity of the unit. The
Minimum Circuit Ampacity is indicated on the
nameplate located on the side panel of the unit.
Refer to this nameplate to choose the right
cable, fuse, or switch.
c. Using wire strippers, strip the rubber jacket
from both ends of the signal cable to reveal
approximately 5.9in(150mm) of wire.
d. Strip the insulation from the ends.
e. Using a wire crimper, crimp u-lugs on the ends.
Note: When connecting the wires, strictly follow the
wiring diagram found inside the electrical box cover.
2. Remove the 2 screws xed on the front right
panel, then take it down to perform wire
connections (for double fan units).
Unscrew the big handle and remove it (for single
fan outdoor units).
3. Connect the u-lugs to the terminals and match the
wire colors/labels with the labels on the terminal
block. Firmly screw the u-lug of each wire to its
corresponding terminal.
4. Clamp down the cable with the cable clamp.
INSTALLATION
3
mrcool.com31
5. Insulate unused wires with electrical tape.
Keep them away from any electrical or metal
parts.
6. Reinstall the cover of the electric control box.
3.8 Test Operation
Conrmthefollowingpointsbeforethetest
operation:
• The indoor and outdoor unit are installed
properly.
• Piping and wiring are properly connected.
• Be sure that there are no obstacles near the
inlet and outlet of the unit that might cause poor
performance or product malfunction.
• The refrigeration system does not leak.
• The drainage system is unimpeded and draining
to a safe location.
• The heating insulation is properly installed.
• The grounding wires are properly connected.
• The length of the piping and the added refrigerant
stow capacity have been recorded.
• Power voltage is the correct voltage for the air
conditioner.
CAUTION
Failure to perform the test run may result in unit
damage, property damage, or personal injury.
Test Run Instructions:
1. Open both the liquid and gas stop valves.
2. Turn on the main power switch and allow the unit
to warm up.
3. Set the air conditioner to COOL mode and check
the following points:
Indoor Unit
• Double check to see if the room temperature is
being registered correctly.
• Be sure the manual buttons on the indoor unit
work properly.
• Check to see that the drainage system is
unimpeded and draining smoothly.
• Be sure there is no vibration or abnormal noise
during operation.
Outdoor Unit
• Check to see if the refrigeration system is leaking.
• Make sure there is no vibration or abnormal noise
during operation.
• Be sure the wind, noise, and water generated by
the unit do not disturb your neighbors or pose a
safety hazard.
Drainage Test:
1. Be sure the drainpipe ows smoothly. New
buildings should perform this test before nishing
the ceiling.
2. Turn on the main power switch and run the air
conditioner in COOL mode.
3. Check to see that the water is discharged. It may
take up to one minute before the unit begins to
drain depending on the drainpipe.
4. Make sure that there are no leaks in any of the
piping.
5. Stop the air conditioner. Turn o the main power
switch and reinstall the test cover.
INSTALLATION
3
4.1 Abbreviation
Abbreviation Element
T1 Indoor room temperature
T2 Coil temperature of evaporator
T3 Coil temperature of condenser
T4 Outdoor ambient temperature
TP Compressor discharge temperature
Tsc Adjusted setting temperature
CDIFTEMP Cooling shutdown temperature
HDIFTEMP2 Heating shutdown temperature
TCDE1 Exit defrost temperature 1
TCDE2
Exit defrost temperature 2 (maintain
for a period of time)
TIMING_
DEFROST_
TIME
Enter defrost time
Unit Element Abbreviations:
In this manual, such as CDIFTEMP, HDIFTEMP2,
TCDE1, TCDE2, TIMING_DEFROST_TIME...etc., they are
well-setting parameter of EEPROM.
Fan Mode:
When fan mode is activated:
• The outdoor fan and compressor are stopped.
Cooling Mode:
Reach the congured temperature:
1. When the compressor runs continuously for less
than 120 minutes.
• If the following conditions are satised, the
compressor ceases operation.
• Calculated frequency(fb) is less than minimum
limit frequency(FminC).
• Compressor runs at FminC more than ten
minutes.
mrcool.com 32
BASIC FUNCTIONS
4
• Indoor room temperature(T1) is lower than or
equal to (Tsc-CDIFTEMP-0.9°F(0.5°C).
2. When the compressor runs continuously for more
than 120 minutes.
• If the following conditions are satised, the
compressor ceases operation.
• Calculated frequency(fb) is less than minimum
limit frequency(FminC).
• Compressor runs at FminC more than 10
minutes.
• When the indoor room temperature(T1) is lower
than or equal to (Tsc-CDIFTEMP).
Note: CDIFTEMP is EEPROM setting parameter. It is
35.6°F(2°C) normally.
3. If one of the following conditions is satised, do
not judge protective time.
• Compressor running frequency is more than test
frequency.
• When the compressor running frequency is
equal to the test frequency, the outdoor ambient
temperature(T4) is more than 59°F(15°C) or
outdoor ambient sensor(T4) fault.
• Change the setting temperature.
• Turning on/o turbo or sleep function.
• Various frequency limit shutdown occurs.
Outdoor Fan Control:
• The outdoor unit will be ran at dierent fan
speeds according to the outdoor ambient
temperature(T4) and compressor frequency.
• For dierent outdoor units, the fan speeds are
dierent.
Condenser Temperature Protection
When the condenser temperature exceeds a
congured value, the compressor ceases operation.
Heating Mode:
Compressor Control:
1. Reach the congured temperature
• If the following conditions are satised, the
compressor ceases operation.
• Calculated frequency(fb) is less than minimum
limit frequency(FminH).
• Compressor runs at FminH more than 10
minutes.
• T1 is higher than or equal to Tsc+HDIFTEMP2.
Note: HDIFTEMP2 is EEPROM setting parameter. It is
35.6°F(2°) normally.
• If one of the following conditions is satised, do
not judge protective time.
• Compressor running frequency is more than test
frequency.
• Compressor running frequency is equal to test
frequency, outdoor ambient temperature(T4)
is more than 59°F(15°C), or outdoor ambient
sensor(T4) fault.
• Change setting temperature.
• Turning on/o turbo or sleep function
2. When the current is higher than the predened
safe value, sure protection is activated, causing
the compressor to cease operations.
Outdoor Fan Control:
• The outdoor unit will run at dierent fan speeds
according to the outdoor ambient temperature(T4)
and compressor frequency.
• For dierent outdoor units, the fan speeds are
dierent.
Defrosting Mode:
• The unit enters defrosting mode according
to the temperature value of the condenser
temperature(T3) and outdoor ambient
temperature(T4) as well as the compressor
running time.
• In defrosting mode, the compressor continues
to run, the indoor and outdoor motor will cease
operation, the defrost light of the indoor unit will
turn on, and the "df" symbol is displayed.
• If any one of the following conditions are satised,
defrosting ends and the machine switches to
normal heating mode:
• Condenser temperature(T3) rises above TCDE1.
• Condenser temperature(T3) maintained above
TCDE2 for 80 seconds.
• Unit runs for 15 minutes consecutively in
defrosting mode.
• If the outdoor ambient temperature(T4) is lower
than or equal to -7.6°(-22°C) and the compressor
running time is more than TIMING_DEFROST_
TIME, if any one of the following conditions
are satised, defrosting ends and the machine
switches to normal heating mode:
• Unit runs for 10 minutes consecutively in
defrosting mode.
• Condenser temperature(T3) rises above
50°F(10°C).
• If any one of the following conditions are satised,
the unit enters defrosting mode.
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BASIC FUNCTIONS
4
• If condenser temperature(T3) or outdoor ambient temperature(T4) is lower than 26.6°F(-3°C) for 30
seconds, Ts-T1 is lower than 41°F(5°C) and the compressor running time is more than EE_TIME_DEFROST7.
• If condenser temperature(T3) or outdoor ambient temperature(T4) is lower than 26.6°F(-3°C) for 30
seconds and the compressor running time is more than EE_TIME_DEFROST7+30 minutes.
• If any one of the following conditions are satised, defrosting ends an the machine switches to normal
heating mode:
• Condenser temperature(T3) rises above TCDE1+7.2°(4°C).
• Condenser temperature(T3) maintained above TCDE2+7.2°F(4°C) for 80 seconds.
• Unit runs for 15 minutes consecutively in defrosting mode.
5.1 Safety Caution
WARNING
Besuretoturnoallpowersuppliesordisconnectallwirestoavoidelectricshock.Whilecheckingthe
indoor/outdoorPCB,pleaseequipyourselfwithanti-staticglovesorawriststraptoavoiddamaging
the board.
Electricitywillremainincapacitorsevenwhenthepowersupplyiso.Ensurethecapacitorsarefully
discharged before troubleshooting
Note: If using the inverter test tool for maintenance, remove the big handle from the unit, take out
the detection cable, take out the female end of the cable, and connect the inverter testing tool. After
maintenance is completed, insert the female end back into the port.
Note: This picture is for reference only. Actual appearance may vary.
LEDFlashFrequency:
CAUTION
Do not use a megger for testing as this will damage the compressor.
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5.2 Error Display
Display Error Information Solution
DF
Defrost
Normal display, not
error code
FC
Forced cooling
EC 07
ODU fan speed out of control TS14
EC 71
Over current failure of outdoor DC fan motor TS14
EC 72
Lack phase failure of outdoor DC fan motor TS34
EC 50
ODU temp. sensor error (T3,T4, TP) TS16
EC 51
ODU EEPROM parameter error TS10
EC 52
ODU coil temp. sensor (T3) error TS16
EC 53
ODU ambient temp. sensor (T4) error TS16
EC 54
COMP. discharge temp. sensor (TP) TS16
EC 55
ODU IPM module temperature sensor malfunction TS36
EC 56
IDU coil outlet temp. sensor (T2B) error TS16
EC 57
Refrigerant pipe temperature sensor error TS16
EL 01
IDU & ODU communication error TS11
PC 00
IPM module protection TS19
PC 02
Compressor top (or IPM) temp. protection TS27
PC 06
Discharge temperature protection of compressor TS25
PC 08
Outdoor overcurrent protection TS18
PC 0A
High temperature protection of condenser TS26
PC 0F
PFC module protection TS24
PC 0L
Low ambient temperature protection --
PC 10
ODU low AC voltage protection TS21
PC 11
ODU main control board DC bus high voltage protection TS21
PC 12
ODU main control board DC bus low voltage protection / 341 MCE error TS21
PC 13
The AC power is cut o or the AC voltage detection circuit fails TS29
PC 30
System high pressure protection TS31
PC 31
System low pressure protection TS23
PC 40
Communication error between ODU main chip and compressor driven
chip
TS17
PC 42
Compressor start failure of outdoor unit TS34
PC 43
ODU compressor lack phase protection TS17
PC 45
ODU IR chip drive failure TS35
PC 46
Compressor speed has been out of control TS17
PC 49
Compressor overcurrent failure TS17
LC 06
High temperature protection of Inverter module (IPM) TS28
PH 90
High temperature protection of evaporator TS37
PH 91
Low temperature protection of evaporator TS38
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5.3 Outdoor Unit Point Check Function
• A check switch is included on the auxiliary board.
• Press SW1 to check the unit's status while running. The digital display shows the following codes
each time the SW1 button is pushed.
Number of
Presses
Display Remark
00 Normal display Display running frequency, running state or malfunction code
01 Indoor unit capacity demand code
Actual data*HP*10
If capacity demand code is higher than 99, the digital display tube will show
single digit and tens digit. (For example, the digital display tube show “5.0”,it
means the capacity demand is 15. the digital display tube show “60”,it means
the capacity demand is 6.0)
S communication, the digital display tube will show: “--”
02 Amendatory capacity demand code
03
The frequency after the capacity
requirement transfer
04
The frequency after the frequency
limit
05
The frequency of sending to 341
chip
06
Indoor unit evaporator
temperature (T2)
If the temp. is lower than -9°C, the digital display tube will show “-9”.
If the temp. is higher than 70°C, the digital display tube will show
“70”. If the indoor unit is not connected, the digital display tube will
show: “--”
07 Condenser pipe temp. (T3)
08 Outdoor ambient temp. (T4)
09 Compressor discharge temp. (tp)
The display value is between 0~199°C. If the temp. is lower than
0°C, the digital display tube will show “0”.If the temp. is higher than
99°C, the digital display tube will show single digit and tens digit. ( For
example, If the display shows 0.5, so 0.5 multiplied by 10 to become
5, then added to 100 to become 105°C.)
10 AD value of current The display value is a hex number.
For example, the digital display tube shows “Cd”, so
C*161+d*160=12*16+13=205, it means AD value is 205.
AD value is detected by the chip.
11 AD value of voltage
12 Indoor unit running mode code
S communication: Standby:0, Cooling:1, Heating:2, Fan only 3,Drying:4,
Forced cooling:6, Defrosting: 7,485 communication: Standby:0, Fan only
1,Cooling:2, Heating:3,Forced cooling:4, Drying:6, Self clean:8
13 Outdoor unit running mode code
14 EXV open angle
Actual data/4.
If the value is higher than 99, the digital display shows single and double
digits.
For example, if the digital display shows “2.0”, so 2.0 multiplied by
10 to become 20, then added to 100 to become 120, the EXV open
angle is 120×4=480p.
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Number of
Presses
Display Remark
15 Frequency limit symbol
Bit7
Frequency limit caused by IGBT
radiator
The display value is a
hexadecimal number. For
example, the digital display
show 2A, then Bit5=1, Bit3=1,
and Bit1=1.
This means that a frequency
limit may be caused by T2, T3,
or the current.
Bit6 Frequency limit caused by PFC
Bit5
Frequency limit caused by high
temperature of T2
Bit4
Frequency limit caused by low
temperature of T2
Bit3 Frequency limit caused by T3
Bit2 Frequency limit caused by TP
Bit1 Frequency limit caused by current
Bit0 Frequency limit caused by voltage
16 Outdoor unit fan motor state
O: 0, Turbo:1 High speed:2, Med speed: 3, Low speed: 4, Breeze:5, Super
breeze: 6 other speed:7
17 IGBT radiator temp.
The display value is between 0~130°C. If the temp. is higher than 99°C, the
digital display tube will show single digit and tens digit. (For example, the
digital display tube show “0.5”,it means the IGBT radiator temp. is 105°C. the
digital display tube show “1.6”,it means the IGBT radiator temp. is 116°C)
18 Indoor unit number
The indoor unit can communicate with outdoor unit well.
General:1, Twins:2
19
Evaporator pipe temp. T2 of 1#
indoor unit
If the temp. is lower than 0°C, the digital display tube will show “0”.If the
temp. is higher than 70°C, the digital display tube will show “70”. If the indoor
unit is not connected, the digital display tube will show: “--”(heating T2,
cooling T2B)
S communication, the digital display tube will show: “--”
20
Evaporator pipe temp. T2 of 2#
indoor unit
21 Reserved
22
1# Indoor unit capacity demand
code
Actual data*HP*10
If capacity demand code is higher than 99, the digital display tube will show
single digit and tens digit. (For example, the digital display tube show “5.0”,it
means the capacity demand is 15. the digital display tube show “60”,it means
the capacity demand is 6.0). If the indoor unit is not connected, the digital
display tube will show: “--”
S communication, the digital display tube will show: “--”
23
2# Indoor unit capacity demand
code
24 Reserved
25 Room temp. T1 of 1# indoor unit
If the temp. is lower than -9°C, the digital display tube will show “-9”. If the
temp. is higher than 70°C, the digital display tube will show “70”. If the indoor
unit is not connected, the digital display tube will show: “--”
S communication, the digital display tube will show: “--”
26 Room temp. T1 of 2# indoor unit
If the temp. is lower than 0°C, the digital display tube will show “0”.If the
temp. is higher than 70°C, the digital display tube will show “70”. If the indoor
unit is not connected, the digital display tube will show:“--”
S communication, the digital display tube will show: “--
27 Average room temp. T1
If the temp. is lower than 0°C, the digital display tube will show “0”.If the
temp. is higher than 70° C, the digital display tube will show “70”
28 Reason of stop
29
Evaporator pipe temp. T2b of
1# indoor unit
If the temp. is lower than -9°C, the digital display tube will show “-9”.If
the temp. is higher than 70°C, the digital display tube will show “70”.
If the indoor unit is not connected, the digital display tube will show:
“--”
S communication, the digital display tube will show: “--”
30
Evaporator pipe temp. T2b of
2# indoor unit
If the temp. is lower than 0°C, the digital display tube will show “0”. If
the temp. is higher than 70° C, the digital display tube will show “70”.
If the indoor unit is not connected, the digital display tube will show:
“--”
S communication, the digital display tube will show: “--”
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5.4 Quick Maintenance by Error Code
If you do not have the time to test which specic parts are faulty, you can change the required parts according to
the error code. You can nd the parts to replace by error code in the following table.
PartRequiring
Replacement
Error code
EL 01 EH 50 EC 51 EC 52 EC 53 EC 54 EC 55 EC 56 EC 57
Indoor PCB √ X X X X X X X X
Outdoor PCB √ √ √ √ √ √ √ √ √
ODU coil temp. sensor X √ X √ X X X X X
ODU ambient temp.
sensor
X √ X √ X X X X X
COMP. discharge temp.
sensor
X √ X X √ X X X X
IPM module temperature
sensor
X X X X X √ X X X
IDU coil outlet temp.
sensor
X X X X X X √ X X
Refrigerant pipe
temperature sensor
X X X X X X X √ X
Condenser temperature
sensor
X X X X X X X X √
Reactor √ X X X X X X X X
IPM module board √ X X X X X X X X
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PartRequiring
Replacement
Error code
EC07/
EC 71
PC 00
PC01/
PC10/
PC11/
PC 12
PC 02
PC08/
PC42/
PC44/
PC46/
PC 49
PC 0F PH 90 PH 91
Outdoor PCB √ √ √ √ √ √ X X
Outdoor fan motor √ √ X X √ X X X
Reactor or inductance X √ √ X √ √ X X
Compressor X √ X X X X X X
IPM module board X √ √ X √ X X X
Bridge rectier X √ √ X √ X X X
Evaporator coil
temperature sensor
X X X X X X √ √
PFC module X X X X X √ X X
Additional refrigerant X X X X X X X X
Overload protector X X X √ X X X X
ODU ambient temp.
sensor
X X X X X X X X
Refrigerant pipe
temperature sensor
X X X X X X X X
Indoor fan X X X X X X √ X
Indoor PCB X X X X X X √ √
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PartRequiring
Replacement
Error code
PC 40 EC 72 PC 43 PC 45 PC 06 PC 0A PC 30 PC 31
Outdoor PCB √ √ √ X √ √ √ √
Outdoor fan motor X √ X X X √ √ √
ODU coil temp. sensor X X X X X √ X X
COMP. discharge temp.
sensor
X X X X √ X X X
Compressor X X √ X X X X X
IPM module board X X X √ X X X X
Additional refrigerant X X X X √ √ X √
Electric control box √ X X X X X X X
High pressure switch X X X X X X √ X
Low pressure switch X X X X X X X √
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5.5 Troubleshooting by Error Code
EC 51: EEPROM malfunction error diagnosis and solution.
Description: Indoor or outdoor PCB main chip does not receive feedback from EEPROM chip.
Recommended parts to prepare:
• Indoor PCB
• Outdoor PCB
Troubleshooting and repair:
Remarks:
EEPROM: A read-only memory whose contents can be erased and reprogrammed using a puled
voltage. The location of the EEPROM chip on the indoor and outdoor PCB is shown in the following
image:
Note: This picture is only for reference, actual appearance may vary.
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EL 01: IDU & ODU communication error diagnosis and solution.
Description: The indoor unit does not receive the feedback from the outdoor unit during 110 seconds
and this condition happens 4 times continuously.
Recommended parts to prepare:
• Indoor PCB
• Outdoor PCB
• IPM module board
• Reactor
Troubleshooting and repair:
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Remarks:
• Use a multimeter to test the DC voltage between 2 port (or S or L2 port) and 3 port (or N or S port)
of the outdoor unit. The red pin of the multimeter connects with 2 port (or S or L2 port) while the
black pin is for 3 port (or N or S port).
• When the AC is operating normally, the voltage is moving alternately as positive values and negative
values.
• If the outdoor unit has a malfunction, the voltage will have a positive value.
• While if the indoor unit has a malfunction, the voltage will have a certain value.
Note: This picture and the value are only for reference, actual condition and specic value may vary.
• Use a multimeter to test the resistance of the reactor which does not connect with the capacitor.
• The normal value should be around zero ohms. Otherwise, the reactor must have a malfunction.
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485Communication(S1,S2Communication):
Recommended parts to prepare:
• Signal wires
• Magnet ring
• Indoor PCB
• Outdoor PCB
Troubleshooting and repair:
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EC 07: Fan speed is operating outside of normal range. EC 71: Overcurrent failure
of outdoor DC fan motor diagnosis and solution.
Description: When the indoor/outdoor fan speed keeps too low or too high for a certain time, the LED
displays the failure code and the system turns o.
Recommended parts to prepare:
• Connection wires
• Fan assembly
• Fan motor
• PCB
Troubleshooting and repair:
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Index:
1. OutdoorDCfanmotor(controlchipisinfanmotor)
Power on and make sure the unit is in standby, measure the voltage of pin1-pin3, pin4-pin3 in the fan
motor connector. If the value of the voltage is not in the range showing in the tables below the PCB
will have problems and will need to be replaced.
NO. Color Signal Voltage
1 Red Vs/Vm 192V~380V
2 --- --- ---
3 Black GND 0V
4 White Vcc 13.5-16.5V
5 Yellow Vsp 0~6.5V
6 Blue FG 13.5-16.5V
Index:
1. OutdoorDCfanmotor(controlchipisinoutdoorPCB)
Release the UVW connector and measure the resistance of U-V, U-W, V-W. If the resistance is not equal
to each other the fan motor has a problem and needs to be replaced. Otherwise the PCB has a
problem and needs to be replaced.
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EC52/EC53/EC54/EC56/EC57/EC50:Opencircuitorshortcircuitof
temperature sensor diagnosis and solution.
Description: If the sampling voltage is lower than 0.06V or higher than 4.94V, the LED displays a fault
code.
Recommended parts to prepare:
• Connection wires
• Sensors
• PCB
Troubleshooting and repair:
Note: This picture and the value are only for reference, actual condition and specic value may vary.
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PC 08: Current overload protection. PC 42: Compressor start failure of outdoor
unit. PC 44: ODU zero speed protection. PC 46: Compressor speed has been out of
control. PC 49: Compressor overcurrent failure.
Description: An abnormal current rise is detected by checking the specied current detection circuit.
Recommended parts to prepare:
• Outdoor PCB
• Connection wires
• Bridge rectier
• PFC circuit or reactor
• Refrigeration piping system
• Pressure switch
• Outdoor fan
• IPM module board
Troubleshooting and repair:
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PC 00: IPM malfunction diagnosis and solution.
Description: When the voltage signal the IPM sends to the compressor drive chip is abnormal, the LED
displays a fault code and the system turns o.
Recommended parts to prepare:
• Connection wires
• IPM module board
• Outdoor fan assembly
• Compressor
• Outdoor PCB
• Reactor or inductance
• Bridge rectier
Troubleshooting and repair: At rst test the resistance between every two ports of U, V, W of the
IPM and P, N. If any result of them is 0 or close to 0, the IPM is defective. Otherwise, please follow the
procedure below:
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PC01: over voltage or too low voltage protection. PC 10: ODU low AC voltage
protection. PC 11: ODU main control board DC bus high voltage protection. PC 12:
ODUmaincontrolboardDCbuslowvoltageprotection/341MCEerrordiagnosis
and solution.
Description: Abnormal increases or decreases in voltage are detected by checking the specied
voltage detection circuit.
Recommended parts to prepare:
• Power supply wires
• IPM module board
• Outdoor PCB
• Bridge rectier
• PFC circuit or reactor
Troubleshooting and repair:
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PC 40: Communication error between ODU main chip and compressor driven chip
diagnosis and solution.
Description: The main PCB cannot detect the IPM board.
Recommended parts to prepare:
• Connection wires
• Outdoor PCB
• IPM module board
• Electric control box
Troubleshooting and repair:
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PC 0F: PFC module protection diagnosis and solution.
Description: Outdoor PCB detects PFC signal is low voltage or DC voltage is lower than 340V for 6s
when quick check.
Recommended parts to prepare:
• Connection wires
• Outdoor PCB
• Inductance
• PFC circuit or IPM module board
Troubleshooting and repair:
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PC 06: Discharge temperature protection of compressor diagnosis and solution.
Description: When the compressor discharge temperature (T5) is more than 115°C for 10 seconds,
the compressor ceases operation and does not restart until T5 is less than 90°C.
Recommended parts to prepare:
• Connection wires
• Outdoor PCB
• Discharge temperature sensor
• Refrigerant
Troubleshooting and repair:
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PC 0A: High temperature protection of condenser diagnosis and solution.
Description: The unit will stop when the condenser temperature is higher than 65°C, and runs again
when it is less than 52°C.
Recommended parts to prepare:
• Connection wires
• Condenser temperature sensor
• Outdoor fan
• Outdoor main PCB
• Refrigerant
Troubleshooting and repair:
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PC02/LC06:Compressortop(orIPM)temp.protectiondiagnosisandsolution.
Description: For some models with an overload protector, if the sampling voltage is not 5V, the LED
will display a fault code. If the temperature of the IPM module is higher than a certain value, the LED
will display a fault code. Models without an overload protector should be diagnosed according to the
second owchart.
Recommended parts to prepare:
• Connection wires
• Outdoor PCB
• IPM module board
• High pressure protector
• System blockages
Troubleshooting and repair:
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PC 30: System high pressure protection diagnosis and solution.
Description: The outdoor pressure switch cuts o the system because of high pressure ( being higher
than 638PSI (4.4MPA)) .
Recommended parts to prepare:
• Connection wires
• Pressure switch
• Outdoor fan
• Outdoor main PCB
Troubleshooting and repair:
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PC 31: System low pressure protection diagnosis and solution.
Description: The outdoor pressure switch cuts o the system because of low pressure ( being lower
than 18.85PSI (0.13MPA)) .
Recommended parts to prepare:
• Connection wires
• Outdoor PCB
• Low pressure protector
• Refrigerant
Troubleshooting and repair:
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EC 72: Lack phase failure of the outdoor DC fan motor diagnosis and solution.
Description: When the three-phase sampling current of the DC motor is abnormal, especially when
the current of one or more phases is always small and almost 0, the LED displays an error code.
Recommended parts to prepare:
• Connection wires
• Fan motor
• Outdoor PCB
Troubleshooting and repair:
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PC 43: ODU compressor lack phase protection diagnosis and solution.
Description: When the three-phase sampling current of the DC motor is abnormal, especially when
the current of one or more phases is always small and almost 0, the LED displays an error code.
Recommended parts to prepare:
• Connection wires
• Compressor
• Outdoor PCB
Troubleshooting and repair:
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PC 45: ODU IR chip drive failure diagnosis and solution.
Description: When the IR chip detects its own parameter error, the LED displays the fault code when
powered on.
Recommended parts to prepare:
• Inverter module PCB
Troubleshooting and repair:
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EC 55: ODU IPM module temperature sensor malfunction diagnosis and solution.
Description: If the sampling voltage is 0V or 5V, the LED displays a fault code.
Recommended parts to prepare:
• IPM module PCB
• Connection wires
• Sensors
• Outdoor main PCB
Troubleshooting and repair:
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PH 90: High temperature protection of evaporator diagnosis and solution.
Description: When the evaporator coil temperature is more than 140°F (60°C) in heating mode the
unit stops. It starts again only when the evaporator coil temperature is less than 125.6°F (52°C).
Recommended parts to prepare:
• Connection wires
• Evaporator coil temperature sensor (T2)
• Indoor fan
• Indoor main PCB
Troubleshooting and repair:
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PH 91: Low temperature protection of evaporator diagnosis and solution.
Description: When the evaporator coil temperature is lower than 32°F (0°C) in cooling or drying mode
the unit stops. It starts again only when the evaporator coil temperature is more than 41°F (5°C) .
Recommended parts to prepare:
• Connection wires
• Evaporator coil temperature sensor (T2)
• Indoor main PCB
Troubleshooting and repair:
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5.6 Check Procedures
WARNING
Besuretoturnoallpowersuppliesordisconnectallwirestoavoidelectricshock.Operateonlyafter
thecompressorandcoilhasreturnedtonormaltemperatureincaseofinjury.
1. Disconnect the temperature sensor from the PCB.
2. Measure the resistance value of the sensor using a multi-meter.
3. Check corresponding temperature sensor resistance value table.
Temperature Sensor Check:
Note: The picture and the value are for reference only, actual condition and specic values may vary.
Compressor Check:
1. Disconnect the compressor power cord from the outdoor PCB.
2. Measure the resistance value of each winding using a multi-meter.
3. Check the resistance value of each winding in the following table.
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TROUBLESHOOTING
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Resistance Value KSK103D33UEZ3 KSN140D58UFZ KTF250D22UMT KTN110D42UFZ KTF420D62UNT
Blue-Red
2.13Ω 1.86Ω 0.75Ω 1.82Ω 0.86Ω
Blue-Black
Red-Black
Resistance Value KTN150D30UFZA KTM240D46UKT2 KTF310D43UMT
ETPQ420D1UMUA
ETPQ440D1UMUB
KTQ420D1UMU
EKPQ440D1UMUB
MTH356UKRC8FQL
Blue-Red
1.02Ω 1.04Ω 0.65Ω 0.37Ω 0.487Ω
Blue-Black
Red-Black
Resistance Value MTH550UKPC8FU
Blue-Red
0.295Ω
Blue-Black
Red-Black
Note: The picture and the value are for reference only, actual condition and specic values may vary.
mrcool.com65
TROUBLESHOOTING
5
WARNING
Electricityremainsincapacitorsevenwhenthepowersupplyiso.Ensurethecapacitorsarefully
discharged before troubleshooting.
IPM Continuity Check:
1. Turn o the outdoor unit and disconnect the power supply.
2. Discharge electronic capacitors and ensure all energy-storage units have been discharged.
3. Disassemble the outdoor PCB or disassemble the IPM board.
4. Measure the resistance value between P and U (U,W,N), U(V,W) and N.
Digital tester Resistance Value Digital Tester Resistance Value
(+)Red (-)Black
∞
(Several MΩ)
(+)Red (-)Black
∞
(Several MΩ)
P
N U
N
U V
V W
W -
Or test the conductivity of IPM with diode mode.
Needle-type Tester
Normal Value
Needle-Type Tester
Normal Value
Red Black Red Black
P
U
Open-Circuit N
U
0.3-0.5VV V
W W
Needle-type Tester
Normal Value
Needle-Type Tester
Normal Value
Red Black Red Black
P
U
0.3-0.5V N
U
Open-CircuitV V
W W
Note: The picture and the value are for reference only, actual condition and specic values may vary.
mrcool.com 66
TROUBLESHOOTING
5
Normal Voltage of P and N:
208-230V(1-phase)
In Standby
Around 310VDC
In Operation
With passive PFC module With partial active PFC module With fully active PFC module
>200VDC >310VDC >370VDC
Reactor Check:
Measure the resistance of the reactor. The normal resistance should be around 0.1 ohm and if not the
reactor has a malfunction.
4-Way Valve Check:
1. Power on, use a digital tester to measure the voltage. When the unit is operating in cooling it is 0V.
When the unit operates in heating it is about equal to the power supply voltage. ( If the value of the
voltage is not in range, the PCB has a problem and needs to be replaced).
2. Turn o the power and use a digital tester to measure the resistance. The value should be
1.8~2.5KΩ.
EXV(EEV)Check:
1. Turn o the outdoor unit and disconnect the power supply.
2. Disconnect the connectors of the EXV.
3. Measure the resistance value between Red and Blue(Yellow); Brown and Orange(White).
Resistance to EXV coil:
Color of Lead
Winding
Normal Value
Red-Blue
About 50Ω
Red-Yellow
Brown-Orange
Brown-White
mrcool.com67
°C °F K Ohm °C °F K Ohm °C °F K Ohm °C °F K Ohm
-20 -4 542.7 20 68 68.66 60 140 13.59 100 212 3.702
-19 -2 511.9 21 70 65.62 61 142 13.11 101 214 3.595
-18 0 483 22 72 62.73 62 144 12.65 102 216 3.492
-17 1 455.9 23 73 59.98 63 145 12.21 103 217 3.392
-16 3 430.5 24 75 57.37 64 147 11.79 104 219 3.296
-15 5 406.7 25 77 54.89 65 149 11.38 105 221 3.203
-14 7 384.3 26 79 52.53 66 151 10.99 106 223 3.113
-13 9 363.3 27 81 50.28 67 153 10.61 107 225 3.025
-12 10 343.6 28 82 48.14 68 154 10.25 108 226 2.941
-11 12 325.1 29 84 46.11 69 156 9.902 109 228 2.86
-10 14 307.7 30 86 44.17 70 158 9.569 110 230 2.781
-9 16 291.3 31 88 42.33 71 160 9.248 111 232 2.704
-8 18 275.9 32 90 40.57 72 162 8.94 112 234 2.63
-7 19 261.4 33 91 38.89 73 163 8.643 113 235 2.559
-6 21 247.8 34 93 37.3 74 165 8.358 114 237 2.489
-5 23 234.9 35 95 35.78 75 167 8.084 115 239 2.422
-4 25 222.8 36 97 34.32 76 169 7.82 116 241 2.357
-3 27 211.4 37 99 32.94 77 171 7.566 117 243 2.294
-2 28 200.7 38 100 31.62 78 172 7.321 118 244 2.233
-1 30 190.5 39 102 30.36 79 174 7.086 119 246 2.174
0 32 180.9 40 104 29.15 80 176 6.859 120 248 2.117
1 34 171.9 41 106 28 81 178 6.641 121 250 2.061
2 36 163.3 42 108 26.9 82 180 6.43 122 252 2.007
3 37 155.2 43 109 25.86 83 181 6.228 123 253 1.955
4 39 147.6 44 111 24.85 84 183 6.033 124 255 1.905
5 41 140.4 45 113 23.89 85 185 5.844 125 257 1.856
6 43 133.5 46 115 22.89 86 187 5.663 126 259 1.808
7 45 127.1 47 117 22.1 87 189 5.488 127 261 1.762
8 46 121 48 118 21.26 88 190 5.32 128 262 1.171
9 48 115.2 49 120 20.46 89 192 5.157 129 264 1.674
10 50 109.8 50 122 19.69 90 194 5 130 266 1.632
11 52 104.6 51 124 18.96 91 196 4.849
12 54 99.69 52 126 18.26 92 198 4.703
13 55 95.05 53 127 17.58 93 199 4.562
14 57 90.66 54 129 16.94 94 201 4.426
15 59 86.49 55 131 16.32 95 203 4.294
16 61 82.54 56 133 15.73 96 205 4.167
17 63 78.79 57 135 15.16 97 207 4.045
18 64 75.24 58 136 14.62 98 208 3.927
19 66 71.86 59 138 14.09 99 210 3.812
TemperatureSensorResistanceValueTable(°C-K)
TEMPERATURE SENSOR RESISTANCE TABLE
6
mrcool.com 68
OtherTemperatureSensorResistanceValueTable(°C-K)
°C °F K Ohm °C °F K Ohm °C °F K Ohm °C °F K Ohm
-20 -4 115.266 20 68 12.6431 60 140 2.35774 100 212 0.62973
-19 -2 108.146 21 70 12.0561 61 142 2.27249 101 214 0.61148
-18 0 101.517 22 72 11.5 62 144 2.19073 102 216 0.59386
-17 1 96.3423 23 73 10.9731 63 145 2.11241 103 217 0.57683
-16 3 89.5865 24 75 10.4736 64 147 2.03732 104 219 0.56038
-15 5 84.219 25 77 10 65 149 1.96532 105 221 0.54448
-14 7 79.311 26 79 9.55074 66 151 1.89627 106 223 0.52912
-13 9 74.536 27 81 9.12445 67 153 1.89627 107 225 0.51426
-12 10 70.1698 28 82 8.71983 68 154 1.83003 108 226 0.49989
-11 12 66.0898 29 84 8.3356 69 156 1.76647 109 228 0.486
-10 14 62.2756 30 86 7.97078 70 158 1.70547 110 230 0.47256
-9 16 58.7079 31 88 7.62411 71 160 1.64691 111 232 0.45957
-8 18 56.3694 32 90 7.29464 72 162 1.59068 112 234 0.44699
-7 19 52.2438 33 91 6.98142 73 163 1.53668 113 235 0.43482
-6 21 49.3161 34 93 6.68355 74 165 1.48481 114 237 0.42304
-5 23 46.5725 35 95 6.40021 75 167 1.43498 115 239 0.41164
-4 25 44 36 97 6.13059 76 169 1.38703 116 241 0.4006
-3 27 41.5878 37 99 5.87359 77 171 1.34105 117 243 0.38991
-2 28 39.8239 38 100 5.62961 78 172 1.29078 118 244 0.37956
-1 30 37.1988 39 102 5.3689 79 174 1.25423 119 246 0.36954
0 32 35.2024 40 104 5.17519 80 176 1.2133 120 248 0.35982
1 34 33.3269 41 106 4.96392 81 178 1.17393 121 250 0.35042
2 36 31.5635 42 108 4.76253 82 180 1.13604 122 252 0.3413
3 37 29.9058 43 109 4.5705 83 181 1.09958 123 253 0.33246
4 39 28.3459 44 111 4.38736 84 183 1.06448 124 255 0.3239
5 41 26.8778 45 113 4.21263 85 185 1.03069 125 257 0.31559
6 43 25.4954 46 115 4.04589 86 187 0.99815 126 259 0.30754
7 45 24.1932 47 117 3.88673 87 189 0.96681 127 261 0.29974
8 46 22.5662 48 118 3.73476 88 190 0.93662 128 262 0.29216
9 48 21.8094 49 120 3.58962 89 192 0.90753 129 264 0.28482
10 50 20.7184 50 122 3.45097 90 194 0.8795 130 266 0.2777
11 52 19.6891 51 124 3.31847 91 196 0.85248 131 268 0.27078
12 54 18.7177 52 126 3.19183 92 198 0.82643 132 270 0.26408
13 55 17.8005 53 127 3.07075 93 199 0.80132 133 271 0.25757
14 57 16.9341 54 129 2.95896 94 201 0.77709 134 273 0.25125
15 59 16.1156 55 131 2.84421 95 203 0.7537 135 275 0.24512
16 61 15.3418 56 133 2.73823 96 205 0.73119 136 277 0.23916
17 63 14.6181 57 135 2.63682 97 207 0.68844 137 279 0.23338
18 64 13.918 58 136 2.53973 98 208 0.66818 138 280 0.22776
19 66 13.2631 59 138 2.4467 99 210 0.64862 139 282 0.22231
6
TEMPERATURE SENSOR RESISTANCE TABLE
mrcool.com69
Pressure Temperature Pressure Temperature
Kpa Bar PSI °C °F Kpa Bar PSI °C °F
58.196 0.58 8.44 -60 -76 935.23 9.35 135.64 8 46.4
61.517 0.62 8.92 -59 -74.2 963.75 9.64 139.78 9 48.2
64.988 0.65 9.43 -58 -72.4 992.93 9.93 14401 10 50
68.615 0.69 9.95 -57 -70.6 1022.8 10.23 148.34 11 51.8
72.402 .072 10.50 -56 -68.8 1053.3 10.53 152.76 12 53.6
76.354 0.76 11.07 -55 -67 1084.5 10.85 157.29 13 55.4
80.478 0.80 11.67 -54 -65.2 1116.4 11.16 161.91 14 57.2
84.776 0.85 12.30 -53 -63.4 1149 11.49 166.64 15 59
89.256 0.89 12.95 -52 -61.6 1182.3 11.82 171.47 16 60.8
93.923 0.94 13.62 -51 -59.8 1216.3 12.16 176.40 17 62.6
98.781 0.99 14.33 -50 -58 1251.1 12.51 181.45 18 64.4
103.84 1.04 15.06 -49 -56.2 1286.6 12.87 186.60 19 66.2
109.1 1.09 15.82 -48 -54.4 1322.8 13.23 191.85 20 68
114.56 1.15 16.61 -47 -52.6 1359.9 13.60 197.23 21 69.8
120.25 1.20 17.44 -46 -50.8 1397.7 13.98 202.71 22 71.6
126.15 1.26 18.30 -45 -49 1436.3 14.36 208.31 23 73.4
132.28 1.32 19.18 -44 -47.2 1475.7 14.76 214.02 24 75.2
138.64 1.39 20.11 -43 -45.4 1515.9 15.16 219.85 25 77
145.24 1.45 21.06 -42 -43.6 1557 15.57 225.82 26 78.8
152.09 1.52 22.06 -41 -41.8 1598.9 15.99 231.89 27 80.6
159.18 1.59 23.09 -40 -40 1641.6 16.42 238.09 28 82.4
166.54 1.67 24.15 -39 -38.2 1685.2 16.85 244.41 29 84.2
174.15 1.74 25.26 -38 -36.4 1729.7 17.30 250.86 30 86
182.04 1.82 26.40 -37 -34.6 1775 17.75 257.43 31 87.8
190.2 1.90 27.59 -36 -32.8 1821.3 18.21 264.15 32 89.6
198.65 1.99 28.81 -35 -31 1868.4 18.68 270.98 33 91.4
207.39 2.07 30.08 -34 -29.2 1916.5 19.17 277.95 34 93.2
216.42 2.16 31.39 -33 -27.4 1965.6 19.66 285.08 35 95
225.76 2.26 32.74 -32 -25.6 2015.5 20.16 292.31 36 96.8
235.41 2.35 34.14 -31 -23.8 2066.5 20.67 299.71 37 98.6
245.37 2.45 35.59 -30 -22 2118.4 21.18 307.24 38 100.4
255.67 2.56 37.08 -29 -20.2 2171.3 21.71 314.19 39 102.2
266.29 2.66 38.62 -28 -18.4 2225.2 22.25 322.73 40 104
277.25 2.77 40.21 -27 -16.6 2280.2 22.80 330.70 41 105.8
288.56 2.89 41.85 -26 -14.8 2336.1 23.36 38.81 42 107.6
300.22 3.00 43.54 -25 -13 2393.2 23.93 347.09 43 109.4
312.24 3.12 45.28 -24 -11.2 2451.3 24.51 355.52 44 111.2
324.63 3.25 47.08 -23 -9.4 2510.4 25.10 364.09 45 113
337.39 3.37 48.93 -22 -7.6 2570.7 25.71 372.84 46 114.8
350.54 3.51 50.84 -21 -5.8 2632.1 26.32 381.74 47 116.6
364.08 3.64 52.80 -20 -4 2694.7 26.95 390.82 48 118.4
378.02 3.78 54.83 -19 -2.2 2758.33 27.58 400.04 49 120.2
392.37 3.92 56.91 -18 -0.4 2823.2 28.23 409.46 50 122
407.13 4.07 59.05 -17 1.4 2889.3 28.89 419.04 51 123.8
System Pressure Table-R454B
SYSTEM PRESSURE TABLE
7
mrcool.com 70
Pressure Temperature Pressure Temperature
Kpa Bar PSI °C °F Kpa Bar PSI °C °F
422.31 4.22 61.25 -16 3.2 2956.5 29.57 428.79 52 125.6
437.92 4.38 63.5 -15 5 3025 30.25 438.72 53 127.4
453.98 4.54 65.84 -14 6.8 3094.7 30.95 448.83 54 129.2
470.47 4.70 68.23 -13 8.6 3165.7 31.66 459.13 55 131
487.43 4.87 70.69 -12 10.4 3238.1 32.38 469.63 56 132.8
504.84 5.05 73.22 -11 12.2 3311.7 33.12 480.30 57 134.6
522.73 5.23 75.81 -10 14 3386.7 33.87 491.18 58 136.4
541.1 5.41 78.48 -9 15.8 3463 34.63 502.25 59 138.2
559.95 5.60 81.21 -8 17.6 3540.7 35.41 513.52 60 140
579.31 5.79 84.02 -7 19.4 3619.9 36.20 525.00 61 141.8
599.16 5.99 86.90 -6 21.2 3700.5 37.01 536.69 62 143.6
619.54 6.20 89.85 -5 23 3782.7 37.83 548.61 63 145.4
640.43 6.40 92.88 -4 24.8 3866.3 38.66 560.74 64 147.2
661.86 6.62 95.99 -3 26.6 3951.5 39.52 573.10 65 149
683.82 6.84 99.18 -2 28.4 4038.3 40.38 585.69 66 450.28
706.34 7.06 102.44 -1 30.2 4126.8 41.27 598.52 67 152.6
729.41 7.29 105.79 0 32 4217 42.17 611.60 68 154.4
753.06 7.53 109.22 1 33.8 4309 43.09 624.95 69 156.2
777.28 7.77 112.73 2 35.6 4402.9 44.03 638.56 70 158
802.08 8.02 116.33 3 37.4 4498.7 44.99 652.46 71 159.8
827.47 8.27 120.01 4 39.2 4596.5 45.97 666.64 72 161.6
853.49 8.53 123.78 5 41 4696.5 46.97 681.15 73 163.4
880.11 8.80 127.64 6 42.8 4798.9 47.99 696.00 74 165.5
907.35 9.07 131.60 7 44.6 4904.1 49.04 711.25 75 167
System Pressure Table-R454B Cont.
7
SYSTEM PRESSURE TABLE
Olympus Series
E-Star®
Mini-Split System
Service Manual
The design and specications of this product and/or manual are subject to change without prior notice.
Consult with the sales agency or manufacturer for details.
