Olympus Series
Multi-Zone
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.
MULTI*-*HP230C-O
O-*-HP-WMAH-230C-O
DUCT-*HP-230B-O
CASSETTE*HP-230C-O
This product utilizes R-454B refrigerant
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CONTENTS
SAFETY ............................................................................................................................... 2
SPECIFICATIONS ............................................................................................................... 9
2.1 Model Reference .................................................................................................. 9
2.2 Pipe Length & Drop Height ................................................................................. 9
2.3 Indoor Unit Combination ................................................................................. 10
2.4 Refrigeration Cycle Diagrams .......................................................................... 12
2.5 Electrical Wiring Diagrams ............................................................................... 14
ELECTRONIC FUNCTIONS .............................................................................................. 23
OUTDOOR UNIT DISASSEMBLY ..................................................................................... 24
4.1 Dimensions ......................................................................................................... 24
4.2 Outdoor Disassembly ....................................................................................... 27
4.3 Fan Assembly ..................................................................................................... 42
TROUBLESHOOTING ...................................................................................................... 48
5.1 Error Display....................................................................................................... 48
5.2 Outdoor Unit Point Check Function ................................................................ 49
5.3 Quick Maintenance by Error Code .................................................................. 53
5.4 Troubleshooting by Error Code ....................................................................... 56
5.5 Check Procedures .............................................................................................. 80
TEMPERATURE SENSOR RESISTANCE TABLE ............................................................... 84
SYSTEM PRESSURE TABLE .............................................................................................. 86
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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6
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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8
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
MULTI3-18HP230C-O 18K
208/230B~,
60Hz, 1Phase
MULTI4-27HP230C-O 27K
MULTI5-36HP230C-O 36K
MULTI6-48HP230C-O 48K
2.2 Pipe Length & Drop Height
Be sure that the length of the refrigerant pipe and the drop height between the indoor and outdoor units meet
the requirements shown in the following table.
1 drive 2 1 drive 3 1 drive 4 1 drive 5 1 drive 6
Max. length for all rooms
(ft/m)
131/40 197/60 262/80 262/80 262/80
Max. length for one IU
(ft/m)
82/25 98/30 115/35 115/35 115/35
Max. Height dierence
between IU and OU (ft/m)
49/15 49/15 49/15 49/15 49/15
Max. Height dierence
between IUs (ft/m)
33/10 33/10 33/10 33/10 33/10
• The refrigerant pipe diameter is dierent according to the indoor unit to be connected. When using the
extension pipe, refer to the tables below.
• When the refrigerant pipe diameter is dierent from that of the outdoor units union, additional transfer
connectors need to be used on the outdoor unit.
CAUTION
Indoor Unit
Model PipeDiameter(inch(mm))
9K, 12K
Liquid Φ1/4(Φ6.35
Gas Φ3/8(Φ9.52)
18K
Liquid Φ1/4(Φ6.35)
Gas Φ1/2(Φ12.7)
24K
Liquid Φ3/8(Φ9.52)
Gas Φ5/8(Φ16)
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SPECIFICATIONS
2
Outdoor Unit
Model Pipe Diameter
(inch(mm))
Adapter(inch(mm) Qty
MULTI3-18HP230C-O
Liquid Φ1/4(Φ6.35)*3
Φ3/8(Φ9.52)-->Φ1/2(Φ12.7) 2
Gas Φ3/8(Φ9.52)*3
MULTI4-27HP230C-O
Liquid Φ1/4(6.35)*4
Φ3/8(Φ9.52)-->Φ1/2(Φ12.7)
Φ1/2(Φ12.7)-->Φ3/8(Φ9.52)
3
1
Gas
Φ3/8(Φ9.52)*3
Φ1/2(Φ12.7)*1
MULTI5-36HP230C-O
Liquid Φ1/4(6.35)*5 Φ1/4(Φ6.35)-->Φ3/8(Φ9.52)
Φ1/2(Φ12.7)-->Φ5/8(Φ16)
Φ3/8(Φ9.52)-->Φ1/2(Φ12.7)
Φ1/2(Φ12.7)-->Φ3/8(Φ9.52)
1
1
3
1
Gas
Φ3/8(Φ9.52)*4
Φ1/2(Φ12.7)*1
MULTI6-48HP230C-O
Liquid Φ1/4(Φ6.35)*6 Φ1/4(Φ6.35)-->Φ3/8(Φ9.52)
Φ1/2(Φ12.7)-->Φ5/8(Φ16)
Φ3/8(Φ9.52)-->Φ1/2(Φ12.7)
Φ1/2(Φ12.7)-->Φ3/8(Φ9.52)
2
2
2
2
Gas
Φ3/8(Φ9.52)*4
Φ1/2(Φ12.7)*2
2.3 Indoor Unit Combination
Indoor unit combination for the MULTI3-18HP230C-O
Available Indoor One Unit Two Units
Wall mounted(AG/EP):
9K/12K/18K;
Cassette/Duct/Console:
9K/12K/18K
12 9+9
18 9+12
12+12
Indoor unit combination for the MULTI4-27HP230C-O
Available Indoor One Unit Two Units Three Units Four Units
Wall mounted(AG/EP):
9K/12K/18K/24K;
Cassette/Duct/Console:
9K/12K/18K/24K;
18 9+9 9+9+9 9+9+9+9
24 9+12 9+9+12
9+18 9+9+18
9+24 9+12+12
12+12 12+12+12
12+18
12+24
18+18
mrcool.com11
Indoor unit combination for the MULTI5-36HP230C-O
Available Indoor One Unit Two Units Three Units Four Units Five Units
Wall mounted(AG/EP):
9K/12K/18K/24K;
Cassette/Duct/Console:
9K/12K/18K/24K;
24 9+9 9+9+9 9+9+9+9 9+9+9+9+9
9+12 9+9+12 9+9+9+12 9+9+9+9+12
9+18 9+9+18 9+9+9+18
9+24 9+9+24 9+9+12+12
12+12 9+12+12 9+9+12+18
12+18 9+12+18 9+12+12+12
12+24 9+12+24 12+12+12+12
18+18 9+18+18
12+12+12
12+12+18
12+12+24
12+18+18
Indoor unit combination for the MULTI6-48HP230C-O & MULTI6-55HP230D-O
Available Indoor One Unit Two
Units
Three
Units
Four Units Five Units Six Units
Wall mounted(AG/EP):
9K/12K/18K/24K/36K;
Cassette/Duct/Console:
9K/12K/18K/24K;
36 9+18 9+9+9 9+9+9+9 9+9+9+9+9 9+9+9+9+9+9
9+24 9+18+24 9+9+9+12 9+9+9+9+12 9+9+9+9+9+12
9+36 9+18+36 9+9+9+18 9+9+9+9+18 9+9+9+9+9+18
12+12 12+12+12 9+9+9+24 9+9+9+9+24 9+9+9+9+12+12
12+18 12+12+18 9+9+12+12 9+9+9+12+12 9+9+9+12+12+12
12+24 12+12+24 9+9+12+18 9+9+9+12+18
12+30 12+12+36 9+9+12+24 9+9+9+12+24
12+36 12+18+18 9+9+18+18 9+9+9+18+18
18+18 12+18+24 9+9+18+24 9+9+12+12+12
18+24 18+18+18 9+12+12+12 9+9+12+12+18
18+30 9+12+12+18 9+12+12+12+12
18+36 9+12+12+24 9+12+12+12+18
24+24 9+12+18+18 12+12+12+12+12
24+36 9+12+18+24
9+18+18+18
12+12+12+12
12+12+12+18
12+12+12+24
12+12+18+18
SPECIFICATIONS
2
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12
2.4 Refrigeration Cycle Diagrams
Refrigeration Cycle Diagram of the MULTI3-18HP230C-O
Refrigeration Cycle Diagram of the MULTI4-27HP230C-O
SPECIFICATIONS
2
mrcool.com13
Refrigeration Cycle Diagram of the MULTI5-36HP230C-O
Refrigeration Cycle Diagram of the MULTI6-48HP230C-O & MULTI6-55HP230C-O
SPECIFICATIONS
2
mrcool.com 14
14
SPECIFICATIONS
2
2.5 Electrical Wiring Diagrams
Outdoor Unit
ODU Model ODU Wiring Diagram
MULTI3-18HP230C-O
16022000040630
MULTI4-27HP230C-O
16022300005674
MULTI5-36HP230C-O
16022300005893
MULTI6-48HP230C-O
16022000040750
Outdoor Unit Wiring Diagram
Outdoor Unit Printed Circuit Board Diagram
Outdoor Unit
ODU Model ODU Wiring Diagram
MULTI3-18HP230C-O
17122000062845
MULTI4-27HP230C-O
MULTI5-36HP230C-O
17122300008875
MULTI6-48HP230C-O
17122300007152
mrcool.com15
SPECIFICATIONS
2
Outdoor Unit Wiring Diagram: 16022300005674
mrcool.com 16
16
SPECIFICATIONS
2
Outdoor Unit Wiring Diagram: 16022000040750
mrcool.com17
Outdoor Unit Wiring Diagram: 16022300005893
SPECIFICATIONS
2
mrcool.com 18
18
Outdoor Unit Wiring Diagram: 17122000062845
SPECIFICATIONS
2
mrcool.com19
No. Name NC# Meaning
1 Power Supply
CN11 L_in: connects to N-line (208-230VAC input)
CN12 N_in: Connects to L-line (208-230VAC input)
2
S-A CN4
S: Connects to indoor unit communication (pin1-pin2:
24VDC Pulse wave; pin2-pin3: 208-240VAC input)
S-B CN2
S-C CN34
S-D CN5
S-E CN10
3
EEV-A CN10
Connects to electric expansion valve
EEV-B CN13
EEV-C CN3
EEV-D CN15
EEV-E CN17
4 HEAT_D CN39 Connects to chassis heater, 208-240VAC when ON
5 4-WAY CN38 Connects to 4 way valve, 208-240VAC when ON
6 HEAY_Y CN40 Connects to compressor heater, 208-240VAC when ON
7 T2B CN28
Connects to evaporator coil outlet temperature sensor
T2B
8 T3 T4 TP CN26
Connects to pipe temp. sensor T3, ambient temp.
sensor T4, exhaust temp. sensor TP
9 OLP TEMP. SENSOR CN30
Connects to compressor top temp. sensor (5VDC Pulse
wave)
10 H-PRO, L-PRO CN29
Connects to high and low pressure switch (pin1-pin2 &
pin3-pin4: 5VDC pulse wave)
11 / CN27 Connects to key board CN1
12 TESTPORT CN24/CN14 Used for testing
13 Compressor
U
Connects to compressor: 0VAC (standby), 10-200VAC
(running)
V
W
14 DC-FAN CN32 Connects to DC fan
Note: This section is for reference only. Please take practicality as standard.
SPECIFICATIONS
2
mrcool.com 20
20
Outdoor Unit Wiring Diagram: 17122300007152
SPECIFICATIONS
2
mrcool.com21
No. Name NC# Meaning
1 COMPRESSOR
U
Connects to compressor (Output: 0~30VAC)V
W
2 DC-FAN1 CN32 Connects to DC fan (Output: 0~310VAC)
3 TESTPORT CN45 Used for testing
4 HEAT_Y CN38 Connects to compressor heater (Output: 230VAC)
5 4-WAY
CN37 Connects to 4 way valve 1 (Output: 230VAC)
CN25 Connects to 4 way valve 2 (Output: 230VAC)
CN42 Connects to 4 way valve 3 (Output: 230VAC)
6 HEAT_D CN24 Connects to chassis heater (Output: 230VAC)
7 Power Supply
CN11 N_in: Connects to N-line (230VAC input)
CN12 L_in: Connects to L-line (230VAC input)
8
S-A
CN43
S: Connects to indoor unit communication (230VAC
input)
S-B
S-C
S-D
S-E
S-F
9
TBH-IN TBH-OUT T3B
TF
CN9
Connects to cold plate inlet temp. sensor TBH-IN, cold
plate outlet temp. sensor TBH-OUT, condenser coil
middle temp. sensor T3B, refrigerant tube inlet temp.
sensor TF
10 OLP TEMP. SENSOR CN30
Connects to compressor top temp. sensor (Output
0~5VDC)
11 T2B CN28
Connects to evaporator coil outlet temperature sensor
T2B
12 / CN27 Connects to key board CN1
13 T3 T4 TP CN26
Connects to condenser coil temp. sensor T3, ambient
temp. sensor T4, Exhaust temp. sensor TP (Output:
0~5VDC)
14 H-PRO, L-PRO CN29
Connects to high and low pressure switch (pin1-pin2 &
pin3-pin4:5VDC pulse wave)
SPECIFICATIONS
2
mrcool.com 22
No. Name NC# Meaning
15
EEVA CN17
Connects to electric expansion valve (Output: 0~12VDC)
EEVB CN16
EEVC CN22
EEVE CN14
EEVD CN12
EEVF CN1
EEV1 CN53
EEV2 CN44
EEV3 CN3
16 H_YL CN49 Connects to high pressure sensor
17 DC-FAN2 CN10 Connects to DC fan (Output: 0~310VAC)
Note: This section is for reference only. Please take practicality as standard.
SPECIFICATIONS
2
mrcool.com23
ELECTRONIC FUNCTIONS
3
Abbreviation Element
T1 Indoor room temperature sensor
T2
Middle indoor heat exchanger coil
temperature
T2B
Indoor heat exchanger exhaust coil
temperature (located on the outdoor
unit)
T3 Coil temperature of condenser
T4 Outdoor ambient temperature
T3B Condenser middle temperature
T5 Refrigerant pipe inlet temperature
T6A
Economizer branch inlet
temperature
T6B
Economizer branch outlet
temperature
TP Compressor discharge temperature
Unit Element Abbreviations:
NOTE: T3B, T5, T6A & T6B are only for hyper heat
models.
Main Protection:
Sensor Redundancy and Automatic Shuto
• If one temperature sensor (T3, T4, T2B, or TP)
malfunctions, the unit ceases operation and
displays the corresponding error code.
Automatic Shuto Based on Fan
• If the outdoor fan speed is operating outside of
the normal range, fna lack of phase or fan zero
speed failure, the unit ceases operation.
Inverter Module Protection
• The inverter module has an automatic hsuto
mechanism based on the unit's current and
temperature. If the automatic shuto is initiated,
the corresponding error code is displayed and the
unit ceases operation.
Indoor/Outdoor Units Communication Protection
• If the indoor units do not receive the feedback
signal from the outdoor units for 2 consecutive
minutes or the outdoor units do not receive
the feedback signal from any one of the indoor
units for 3 consecutive minutes, the unit ceases
operation and displays a failure code.
EEPROM Parameter Error
• If the main chip does not receive feedback from
EEPROM chip or parameter check error, the unit
ceases operation.
Automatic Shuto Based on Compressor
• If the compressor speed has been out of control,
compressor lack of phase or voltage too low
failure, the unit ceases operation.
Temperature Protection of Compressor Discharge
• When the discharge temperature of the
compressor rises, the running frequency is
limited. If the discharge temperature is too high,
the compressor stops and then restarts until
the discharge temperature is reduced to normal
range.
Evaporator Anti-Freezing Protection
• The T2 sent from the indoor unit to the outdoor
unit is low, and the unit limits the compressor to
run at a low frequency.
Oil Return
1. If the unit runs at low frequency for a long time,
the unit will run the oil return program to increase
the frequency of the compressor;
2. After the units runs continuously for a period of
time, the unit will run the oil return program to
increase the compressor frequency.
mrcool.com 24
24
OUTDOOR UNIT DISASSEMBLY
4
ODU Model Panel Plate PCB Board
MULTI3-18HP230C-O
X430 PCB board 6
MULTI4-27HP230C-O
D30 PCB board 9
MULTI5-36HP230C-O
MULTI6-48HP230C-O
E30 PCB board 10
PanelPlateX430(1drive2)
4.1 Dimensions
mrcool.com25
OUTDOOR UNIT DISASSEMBLY
4
PanelPlateD30(1drive3&1drive4)
PanelPlateE30(1drive4&1drive5)
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26
PanelPlateE30(1drive6)
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com27
4.2 Outdoor Disassembly
Panel Plate X430
Procedure Illustration
1. Turn o the air conditioner and the power
breaker.
2. Remove the screws of the big handle assembly
and water collector then remove them. (6 screws)
3. Remove the screws of the top cover and then
remove the top cover (3 screws). One of the screws
is located underneath the big handle.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com 28
28
Procedure Illustration
4. Remove the screws of the front panel and then
remove the front panel (7 screws).
5. Remove the screws of the right panel and then
remove the right panel (14 screws, two of them are
used to x the optional rear net).
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com29
OUTDOOR UNIT DISASSEMBLY
4
D30
Procedure Illustration
1. Turn o the air conditioner and the power
breaker.
2. Remove four screws and then remove the big
handle.
3. Remove three screws and then remove the water
collecting cover.
4. Remove the screws on the top cover and then
remove the top cover (4 screws). Two of the screws
are located underneath the big handle.
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com 30
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
5. Remove the screws of the front right panel and
then remove the front right panel (2 screws).
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com31
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
6. Remove the screws of the front panel and then
remove the front panel (9 screws).
7. Remove the screws of the rear net and then
remove the rear net (6 screws).
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com 32
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
6. Remove the screws of the right panel and then
remove the right panel (12 screws)
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com33
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
1. Turn o the air conditioner and the power
breaker.
2. Remove the screws of the big handle and then
remove it (3 screws).
3. Remove the screws of the water collecting cover
and then remove it (3 screws).
4. Unx the four screws of the top cover and then
remove it.
E30
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com 34
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
5. Remove the two screws of the right front panel
and then push it down to unhook the right front
panel from the 9 hooks.
6. Remove the 7 screws of the front panel then
remove the front panel.
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com35
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
7. Unx the screws on the right side of the right
panel (9 screws).
8. Remove the screws on the back of the right panel
and then remove the right panel and rear net (9
screws).
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com 36
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
1. Remove 5 screws of the electrical control box
cover and remove it.
2. Cut the ribbon by a shear and disconnect the
4-way valve connector.
3. Turn over the electronic control box subassembly.
PCB board 6
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com37
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
4. Remove the electronic installing box subassembly
(4 hooks).
5. Remove the support of the electronic control box.
Note: This section is for reference only. Actual unit appearance may vary.
mrcool.com 38
Procedure Illustration
6. Disconnect the connectors from the electronic
control board.
7. Remove the 4 screws and then remove the
electronic control board.
8. Pull out the connector, remove one screw, and
then remove the key board subassembly on the
terminal board.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com39
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
1. Remove the cover of the electrical control box.
2. Disconnect the fan motor connector.
3. Remove 8 xing screws.
4. Turn over the electronic control box subassembly.
Note: This section is for reference only. Actual unit appearance may vary.
PCB board 9
mrcool.com 40
Procedure Illustration
5. Remove 3 screws and then remove the bracket.
6. Disconnect the connectors from the electronic
control board.
7. Remove 3 screws and then remove the electronic
control board.
8. Pull out the connector, remove one screw and
then remove the key board subassembly on the
terminal board.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com41
OUTDOOR UNIT DISASSEMBLY
4
Procedure Illustration
9. Disconnect the connectors from the electronic
control board.
10. Remove 3 screws and then remove the electronic
control board.
11. Pull out the connector, remove one screw and
then remove the key board subassembly on the
terminal board.
Note: This section is for reference only. Actual unit appearance may vary.
PCB board 10
mrcool.com 42
4.3 Fan Assembly
Procedure Illustration
1. Remove the nut securing the fan with a crescent
wrench.
2. Remove the fan.
NOTE: Remove the panel plate before disassembling the fan.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com43
Procedure Illustration
3. Remove the xing screws of the fan motor (4
screws).
4. Remove the fan motor.
Fan Motor
NOTE: Remove the panel plate and the connection of the fan motor on the PCB before
disassembling the fan motor.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com 44
Procedure Illustration
1. Remove the sound blanket (side and top).
Sound Blanket
NOTE: Remove the panel plate before disassembling the sound blanket.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com45
Procedure Illustration
1. Heat up the brazed parts and then detach the
four-way valve and the pipe.
2. Remove the four-way valve assembly with pliers.
Four-Way Valve
WARNINGS
Evacuate the system and conrm that there is no refrigerant left in the system before removing the four-way
valve and the compressor.
NOTE: Remove the panel plate, connection of the four-way valve on PCB before
disassembling the sound blanket.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com 46
Compressor
WARNINGS
Evacuate the system and conrm that there is no refrigerant left in the system before removing the four-way
valve and the compressor.
NOTE: Remove the panel plate, connection of the four-way valve on PCB before
disassembling the sound blanket.
Procedure Illustration
1. Remove the ange nut of the terminal cover and
remove the terminal cover.
2. Disconnect the connectors.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com47
Procedure Illustration
3. Remove the hex nuts and washers securing the
compressor, located on the bottom plate.
4. Heat up the brazed parts and then remove the
discharge pipe and the suction pipe.
5. Lift the compressor from the base pan assembly
with pliers.
Note: This section is for reference only. Actual unit appearance may vary.
OUTDOOR UNIT DISASSEMBLY
4
mrcool.com 48
TROUBLESHOOTING
5
5.1 Error Display
Display Error Information Solution
DF Defrost
Normal display, not error code
FC Forced cooling
EC 07 ODU fan speed out of control TS16
EC 71 Over current failure of outdoor DC fan motor TS16
EC 72 Lack phase failure of outdoor DC fan motor TS23
EC 50 ODU temp. sensor error (T3,T4, TP) TS18
EC 51 ODU EEPROM parameter error TS12
EC 52 ODU coil temp. sensor (T3) error TS18
EC 53 ODU ambient temp. sensor (T4) error TS18
EC 54 COMP. discharge temp. sensor (TP) TS18
EC 55 ODU IPM module temperature sensor malfunction TS42
EC 56 IDU coil outlet temp. sensor (T2B) error TS18
EC 57 Refrigerant pipe temperature sensor error TS18
EC 5A Failure of enthalpy inlet temperature sensor TS18
EC 5b Failure of enthalpy outlet temperature sensor TS18
EC 5E Condenser temperature sensor (T3B) failure TS18
EC 5C Pressure sensor failure TS43
EH C1 Refrigerant sensor detects leakage TS41
EL 01 IDU & ODU communication error TS13
PC 00 IPM module protection TS21
PC 02 Compressor top (or IPM) temp. protection TS21
PC 06 Discharge temperature protection of compressor TS29
PC 08 Outdoor overcurrent protection TS19
PC 0A High temperature protection of condenser TS30
PC 0F PFC module protection TS27
PC 0L Low ambient temperature protection --
PC 10 ODU low AC voltage protection TS23
PC 11 ODU main control board DC bus high voltage protection TS23
PC 12 ODU main control board DC bus low voltage protection / 341 MCE error S23
PC 13 The AC power is cut o or the AC voltage detection circuit fails TS44
PC 30 System high pressure protection TS34
PC 31 System low pressure protection TS36
PC 40 Communication error between ODU main chip and compressor driven chip TS26
PC 43 ODU compressor lack phase protection TS39
PC 44 ODU zero speed protection TS19
PC 45 ODU IR chip drive failure TS40
PC 46 Compressor speed has been out of control TS19
PC 49 Compressor overcurrent failure TS19
PC A1 Condensation protection of refrigerant pipe TS45
LC 06 High temperature protection of Inverter module (IPM) TS32
WARNING
Besuretoturnoallpowersuppliesordisconnectallwirestoavoidelectricshock.Whilecheckingthe
indoor/outdoorPCB,pleaseequipyourselfwithanti-staticglovesorawriststraptoavoiddamaging
the board.
Electricitywillremainincapacitorsevenwhenthepowersupplyiso.Ensurethecapacitorsarefully
discharged before troubleshooting
mrcool.com49
5.2 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
Quantity of indoor units with
working connection
Display Number of indoor unit
02
Outdoor unit running mode
code
Standby: 0, Fan only: 1, Cooling/Drying: 2, Heating: 3, Forced cooling:
6, Forced defrosting: A
03
Indoor unit A capacity
The capacity unit is horse power. If the indoor unit is not connected,
the digital display shows the following: "--"
(6K:0.6HP, 7K:0.8HP, 9K:1.0HP, 12K:1.2HP, 18K:1.5HP, 24K:2.5HP,
30K:3.0HP, 36K:3.2HP)
04
Indoor unit B capacity
05
Indoor unit C capacity
06
Indoor unit D capacity
07
Indoor unit E capacity
08
Indoor unit A capacity demand
code
Normal code*HP
(6K:0.6HP, 7K:0.8HP, 9K:1.0HP, 12K:1.2HP, 18K:1.5HP, 24K:2.5HP,
30K:3.0HP, 36K:3.2HP)
09
Indoor unit B capacity demand
code
10
Indoor unit C capacity demand
code
11
Indoor unit D capacity demand
code
12
Indoor unit E capacity demand
code
13
Outdoor unit amendatory
capacity demand code
14
The frequency corresponding
to the total indoor units'
amendatory capacity demand
15
The frequency after the
frequency limit
16
The frequency sending to
compressor control chip
17
Indoor unit A evaporator outlet
temperature (T2B)
If the temperature is lower than -9°C, the digital display shows "-9". If
the temperature is higher than 70°C, the digital display shows "70". If
the indoor unit is not connected, the digital display shows "--".
18
Indoor unit B evaporator outlet
temperature (T2B)
19
Indoor unit C evaporator outlet
temperature (T2B)
20
Indoor unit D evaporator outlet
temperature (T2B)
21
Indoor unit E evaporator outlet
temperature (T2B)
TROUBLESHOOTING
5
mrcool.com 50
Number of
Presses
Display Remark
22
Indoor unit A room
temperature (T1A)
If the room temperature is lower than 0°C, the digital display shows
"0". If the temperature is higher than 70°C, the digital display shows
"70". If the indoor unit is not connected, the digital display shows:
"--".
23
Indoor unit B room
temperature (T1B)
24
Indoor unit C room
temperature (T1C)
25
Indoor unit D room
temperature (T1D)
26
Indoor unit E room
temperature (T1E)
27
Indoor unit A evaporator
temperature (T2A)
If the temperature is lower than -9°C, the digital display shows "-9". If
the temperature is higher than 70°C, the digital display shows "70". If
the indoor unit is not connected, the digital display shows "--".
28
Indoor unit B evaporator
temperature (T2B)
29
Indoor unit C evaporator
temperature (T2C)
30
Indoor unit D evaporator
temperature (T2D)
31
Indoor unit E evaporator
temperature (T2E)
32
Condenser pipe temperature
(T3)
33
Outdoor ambient temperature
(T4)
34
Compressor discharge
temperature (TP)
The display value is between 30-129°C. If the temperature is lower
than 30°C, the digital display shows "30". If the temperature is higher
than 99°C, the digital display shows single and double digits. 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.
35
AD value of current
The display value is 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 for DIY-MULTI5-36HP230D-O the
actual AD value is AD value plus 60.
36
AD value of AC voltage
37
AD value of DC voltage
38
EXV open angle for A indoor
unit
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.
39
EXV open angle for B indoor
unit
40
EXV open angle for C indoor
unit
41
EXV open angle for D indoor
unit
42
EXV open angle for E indoor
unit
43
MVI open angle (for some
models)
44
EXI open angle (for some
models)
TROUBLESHOOTING
5
mrcool.com51
Number of
Presses
Display Remark
45
Frequency limit symbol
Bit7 Reserved
The display value is a
hexadecimal number. For
example, the digital display
shows 2A, the corresponding
binary is 101010, so Bit5=1,
Bit3=1, and Bit1=1.
This means that a frequency
limit may be caused by current,
IPM or T3.
Bit6
Frequency limit caused by
voltage
Bit5
Frequency limit caused by
voltage
Bit4 Reserved
Bit3
Frequency limit caused by
IPM
Bit2
Frequency limit caused
by Compressor discharge
temperature (T5)
Bit1
Frequency limit caused by
Outdoor heat exchanger pipe
temperature (T3)
Bit0
Frequency limit caused
by Middle indoor heat
exchanger coil temperature
(T2)
46
T2B fault
00:No fault, 01:T2B-A fault, 02:T2B-B fault, 03:T2B-C fault, 04:T2B-D
fault, 05:T2B-E fault, 06:T2B-F fault(the display priority is A-B-C-D-E-F)
47
Average value of T2
(Sum T2 value of all indoor units)(number of indoor units in good
connection)(The heating is the average value of T2, and the cooling is
the average value of T2B)
If the temperature is lower than -9°C, the digital display shows "-9"
48
Outdoor unit fan speed See next list
49
Reason of stop
50~59
Reserved
60
Air injection enthalpy inlet
temperature (for hyper heat
models)
If the temperature is lower than -9°C, the digital display shows "-9". If
the temperature is higher than 70°C, the digital display shows "70". If
the indoor unit is not connected, the digital display shows: "--".
61
Air injection enthalpy outlet
temperature (for hyper heat
models)
62
Condenser coil middle
temperature (for hyper heat
models)
63
Refrigerant tube inlet
temperature (for hyper heat
models)
64
Target discharge temperature
The display value is between 0-199°C, If the temperature is lower
than 30°C, the digital display shows "30". If the temperature is higher
than 99°C, the digital display shows single and double digits. 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.
65
Indoor Unit F capacity
The capacity unit is horse power. If the indoor unit is not connected,
the digital display shows the following "--".
66
Indoor unit F capacity demand
code
Normal code*HP
(9K: 1HP, 12K: 1.2HP, 18K: 1.5HP)
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Number of
Presses
Display Remark
67
Indoor unit F evaporator outlet
temperature (T2BF)
If the temperature if lower than -9°C, the digital display shows "-9". If
the temperature is higher than 70°C, the digital display shows "70". If
the indoor unit is not connected, the digital display shows: "--".
68
Indoor unit F room
temperature (T1F)
If the temperature is lower than 0°C, the digital display shows "0". If
the temperature is higher than 70°C, the digital display shows "70'. If
the indoor unit is not connected, the digital display shows "--".
69
Indoor unit F evaporator
temperature (T2F)
If the temperature is lower than -9°C, the digital display shows "-9". If
the temperature is higher than 70°C, the digital display shows "70". If
the indoor unit is not connected, the digital display shows "--".
70
EXV open angle for F indoor
unit
Actual data/4
If the value is higher than 99, the digital display shows single and
double digits.
71
IPM module temperature
The display value is between 0-199°C. If the temperature is higher
than 99°C, the digital display shows single and double digits. For
example, if the display shows 5.0, so 5.0 multiplied by 10 to become
50, then added to 100 to become 150°C.
72
The high pressure sensor
detects the pressure
corresponding to the
condensation temperature (Tc)
The digital display shows: "--"
73
Reserved
74
Outdoor unit fan speed corresponding table:
Outdoor Unit Fan
Speed
Display
>600rpm 02
>300rpm & <=600rpm 03
<=300rpm 04
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5.3 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 EC 50 EC 51 EC 52 EC 53 EC 54 EC 55 EC 56 EC 57 EC 5A EC 5b EC 5E
Indoor PCB
√ x x x x x x x x x x x
Outdoor PCB
√ √ √ √ √ √ √ √ √ √ √ √
ODU coil temp.
sensor
x √ x √ x x x x x x x x
ODU ambient
temp. sensor
x √ x x √ x x x x x x x
COMP. Discharge
temp. sensor
x √ x x x √ x x x x x x
IPM module
temperature
sensor
x x x x x x √ x x x x x
IDU coil outlet
temp. sensor
x x x x x x x √ x x x x
Refrigerant pipe
temperature
sensor
x x x x x x x x √ x x x
Enthalpy inlet
temperature
sensor
x x x x x x x x x √ x x
Enthalpy outlet
temperature
sensor
x x x x x x x x x x √ x
Condenser
temperature
sensor
x x x x x x x x x x x √
Reactor
√ x x x x x x x x x x x
IPM module
board
√ x x x x x x x x x x x
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PartRequiring
Replacement
Error Code
EC 5C EH C1
EC07/
EC 71
PC 00
PC01/
PC10/
PC11/
PC 12
PC 02
PC08/
PC44/
PC46/
PC 49
PC 13 PC A1 PC 0F
Outdoor PCB √ x √ √ √ √ √ √ √ √
Outdoor fan motor
x x √ √ x x √ x x x
Reactor or
inductance
x x x √ √ x √ x x √
Compressor
x x x √ x x x x x x
IPM module board
x x x √ √ x √ x x x
Bridge rectier
x x x √ √ x √ x x x
Pressure sensor
√ x x x x x x x x x
PFC module
x x x x x x x x x √
Additional refrigerant
x √ x x x x x x x x
Over load protector
x x x x x √ x x x x
ODU ambient temp.
sensor
x x x x x x x x √ x
Refrigerant pipe
sensor
x x x 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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CAUTION
Do not use a megger for testing as this will damage the compressor.
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5.4 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 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.
Note: This picture and the value are only for reference, actual condition and specic value may vary.
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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/EC5A/EC5b/EC5E/EC50:Opencircuitorshort
circuit of 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 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:
CE:Automaticcorrectionofwiring/pipingerror.
Press the "check switch" on the outdoor units PCB board for 5 seconds until the LED displays "CE"
which means this function is working. Approximately 5-10 minutes after the switch is pressed, the
"CE" will disappear and the wiring/piping error will be corrected.
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EH C1: Refrigerant sensor detects leakage or working condition of the refrigerant
sensor is out of range and leakage is detected diagnosis ans solution.
Description: The refrigerant sensor detects a concentration higher than or equal to 10%*LFL for 10
seconds or the refrigerant sensor detects a concentration higher than or equal to 20%*LFL or the multi
mode receives the refrigerant leakage protection fault sent by the outdoor unit.
Recommended parts to prepare:
• Additional refrigerant
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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EC 5C: Pressure sensor failure diagnosis and solution.
Description: If the sampling voltage is lower than 2V or higher than 254V.
Recommended parts to prepare:
• Connection wires
• Sensor
• Outdoor PCB
Troubleshooting and repair:
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PC13:TheACpoweriscutoortheACvoltagedetectioncircuitfailsdiagnosis
and solution.
Description: The machine equipped safety shut-o has detected a power outage from the main
power.
Recommended parts to prepare:
• Outdoor PCB
Troubleshooting and repair:
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PC A1: Condensation protection of refrigerant pip diagnosis and solution.
Description: If the outdoor ambient temperature is higher than a certain set value of the refrigerant
pipe temperature for a period of time, the LED displays a fault code.
Recommended parts to prepare:
• T4 sensor
• T5 sensor
• Main EXV
• Outdoor PCB
Troubleshooting and repair:
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5.5 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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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.
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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.
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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
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°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)
6
TEMPERATURE SENSOR RESISTANCE TABLE
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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
TEMPERATURE SENSOR RESISTANCE TABLE
6
mrcool.com 86
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
7
SYSTEM PRESSURE TABLE
mrcool.com87
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.
SYSTEM PRESSURE TABLE
7
Olympus Series
Multi-Zone
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.
