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: February 26, 2025
Please visit www.mrcool.com/documentation
to ensure you have the latest version of this manual.
This product utilizes R-454B refrigerant
DIY
®
Series
Single-Zone
Mini-Split System
INSTALLATION & OWNER’S MANUAL
DIY-*-HP-WMAH-115D25-O
DIY-*-HP-WMAH-230D25-O
DIY-*-HP-C-115D25-O
DIY-*-HP-C-230D25-O
mrcool.com1
CONTENTS
SAFETY ............................................................................................................................... 2
UNIT OVERVIEW ................................................................................................................ 9
2.1 Packing List........................................................................................................... 9
2.2 Indoor Unit Display .......................................................................................... 10
2.3 Additional Functions ......................................................................................... 11
2.4 Setting Angle of Airow .................................................................................... 12
2.5 Manual Operation ............................................................................................. 13
2.6 Packing & Unpacking the Unit ......................................................................... 13
INDOOR UNIT INSTALLATION ....................................................................................... 14
3.1 Installation Overview ........................................................................................ 14
3.2 Installation Summary........................................................................................ 15
3.3 Location Selection ............................................................................................. 17
3.4 Drilling Wall Opening ........................................................................................ 19
3.5 Refrigerant Pipe & Drain Hose Installation .................................................... 21
3.6 Electrical Wiring ................................................................................................. 25
3.7 Wrap Piping & Cables ........................................................................................ 26
3.8 Mount Indoor Unit ............................................................................................. 27
OUTDOOR UNIT INSTALLATION ................................................................................... 29
4.1 Location Selection ............................................................................................. 29
4.2 Drain Joint Installation ...................................................................................... 30
4.3 Anchor Outdoor Unit ........................................................................................ 31
4.4 Signal & Power Cable Connection ................................................................... 32
4.5 Refrigerant Piping Connection ......................................................................... 33
POST-INSTALLATION ...................................................................................................... 35
5.1 Electrical & Gas Leak Checks ........................................................................... 35
5.2 Test Run .............................................................................................................. 36
5.3 Care & Maintenance .......................................................................................... 37
5.4 Troubleshooting ................................................................................................ 39
5.5 Error Display (Indoor Unit) ............................................................................... 41
5.6 Error Display (Outdoor Unit with Auxiliary Board) ....................................... 42
5.7 Quick Maintenance by Error Code .................................................................. 43
1
2
3
4
5
Contents
This marking indicates that this product should not be disposed with other household wastes
throughout North America. To prevent possible harm to the environment or human health from
uncontrolled waste disposal, recycle it responsibly to promote the sustainable reuse of material
resources. To return your used device, please use the return and collection systems or contact the
retailer where the product was purchased. They can take this product for environmental safe recycling.
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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.
SAFETY
1
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 requiremetns 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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SAFETY
1
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 nto 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
SAFETY
1
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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2.1 Packing List
This system comes with the following accessories. Use all of the installation parts and accessories to
install the unit. Improper installation may result in water leakage, electrical shock and re, or cause the
equipment to fail. The items that are not included with the air conditioner must be purchased separately.
UNIT OVERVIEW
2
PART LOOKS LIKE QUANTITY
Manuals
2 (Installation
& Remote)
Mounting Plate
& Template
1
1- Metal Mounting
Plate
1 - Cardboard
Template
Remote Control 1
Drain Pipe 1
Anchor
5-8 each
(Packaged
Together)
Mounting Plate
Fixing Screw
Smart
Controller Kit
1
DIYPRO
®
Cable 1
Small Filter 1-2
Allen Wrench 1
Non-Adhesive
Tape
1
PART LOOKS LIKE QUANTITY
AAA Battery 2
Remote Control
Holder
1
Fixing Screw for
Remote Control
Holder
2
Insulation
Sleeve
2
Sound-
Absorbent Pads
2
Seal
1
Drain Joint
1
Plastic Wall
Sleeve & Cap
1
Quick
Connect® Line
Set
1
Neoprene
1
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2.2 Indoor Unit Display
UNIT OVERVIEW
2
Only use compatible modules certied for use with the model. Refer to the Electric Auxiliary Heat Model
specication for additional details to ensure proper selection and installation.
Display Code Display Code Meaning
• When Wireless Control feature is activated (For APP control units)
• Displays temperature, operation feature and Error codes:
(for 3 seconds)
• TIMER ON is set (if the unit is OFF, “ ” remains on when TIMER ON is set ).
• SWING, TURBO or SILENCE feature is turned on.
(for 3 seconds)
• TIMER OFF is set.
• SWING, TURBO or SILENCE feature is turned o.
• When defrosting.
• When Active Clean feature is turned on.
• When 46 F(8 C) heating feature is turned on.
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Auto-Restart
In the event that there is a power loss, the unit will
automatically restart with the prior settings once
power has been restored.
Breeze Away
This feature avoids airow from blowing directly on
the body. The louver will set to a 35°angle. The fan will
adjust to continue to maintain a cool atmosphere in
the room.
Wireless Control(For App control units)
Allows you to control your air conditioner using your
mobile phone and a wireless connection. For the USB
device access, replacement, maintenance operations
must be carried out by HVAC Technicians.
Active Clean function
The Active Clean Technology washes away dust when
it adheres to the heat exchanger by automatically
freezing and then rapidly thawing the frost. This
operation is used to produce more condensed water
to improve the cleaning eect, and the cold air will
blow out. After cleaning, the internal wind wheel
then keeps operating with hot air to blow-dry the
evaporator, thus keeping the inside clean. When this
function is turned on, the indoor unit display window
appears “CL ”, after 20 to 45 minutes, the unit will turn
o automatically and cancel the Active Clean function.
Louver Angle Memory
When turning on your unit, the louver will
automatically resume its former angle.
Heat Exchanger Dust Removal Function
This feature helps keep the outdoor coil cleaner
and may extend the duration between regular
maintenance intervals depending on local conditions.
When the unit is turned o, a 10 second delay occurs
then the outdoor fan runs in reverse rotation for 70
seconds. This will blow o loose accumulated dust and
debris.
Refrigerant Leakage Detection
When the system detects a malfunction of the
refrigerant, the indoor unit will automatically display
the following error codes:
“EL0C (System lacks refrigerant )” ,
“EHC1 (Refrigerant sensor detects leakage)”,
“EHC2 (Working condition of the refrigerant sensor is
out of range and leakage is detected)”, “EHC3(Working
condition of the refrigerant sensor is out of range )”, or
“ECC1 (Other indoor unit refrigerant sensor detects
leakage (Multi-zone)”.
When “EHC1” or “EHC2” error occurs, the buzzer will
continue to beep for 5 to 6 minutes before stopping.
You can also press any button on the remote controller
to stop the buzzer.
Note: Error codes of “EHC1”, “EHC2”,“EHC3” and
“ECC1” are only applicable to the units with refrigerant
sensor.
Sleep Operation
The SLEEP function is used to maximize energy usage
while you sleep (and don’t need the same temperature
settings to stay comfortable). When in COOL mode,
press the SLEEP button on remote control. The unit
will increase the temperature by 2°F (1°C) after 1 hour,
and will increase an additional 2°F (1°C) after another
hour. When in HEAT mode, the unit will decrease
the temperature by 2°F (1°C) after 1 hour, and will
decrease an additional 2°F (1°C) after another hour.
The sleep feature will stop after 8 hours and the
system will keep running with nal temperature
setting.
2.3 Additional Functions
Note: When the unit is powered on, a buzzing
sound will be heard to indicate that the unit has
been powered on normally. If there is no sound, it is
possible that there is a problem with the unit. If this
happens, power o and then on again. Also, check
the circuit. Check the indoor display and remote
control for your unit.
(See the Remote Controller Manual for more
features.)
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2.4SettingAngleofAirow
Note: While the unit is on, use the SWING/DIRECT button (Located on the remote control) to set the direction,
or vertical angle, of airow. Please refer to the Remote Control Manual for details.
Do not manually move the louver. To reset the louver, turn o the unit and disconnect from power.
Note on Louver Angles
When using COOL of DRY mode, do not set louver at too vertical of an angle
for long periods of time. This will cause the water to condense, which will
result in water dropping below the unit.
The horizontal angle of the airow must be set manually. To adjust, grip the deector rod and set it to the
preferred position.
The horizontal angle of the airow can also be set by remote control. (Refer to the Remote Control Manual for
instructions.)
DO NOT put your ngers in or near the blower and suction side of the unit. The high-speed fan inside the unit
may cause injury.
CAUTION
When using COOL or HEAT mode, setting the louver at to small an angle can
reduce the performance of the unit due to restricted air ow.
Set the vertical air ow louver to it's maximum angle according to the relative
standards requirement under heating capacity test.
SettingHorizontalAngleofAirow
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2.5 Manual Operation
To Operate the Unit Manually:
1. Open the front panel of the air handler. Note: If there is
a supporting rod located on the left or right side, use that
to secure to panel.
2. Locate the MANUAL CONTROL button on the right-hand
side of the unit.
3. Press the MANUAL CONTROL button one time to activate
FORCED AUTO mode.
4. Press the MANUAL CONTROL button again to activate
FORCED COOLING mode.
5. Press the MANUAL CONTROL button a third time to turn
the unit o.
6. Release the supporting rod (if included), then close the
front panel.
2.6 Packing & Unpacking the Unit
Unpacking the Indoor Unit
1. Cut the sealing tape on the carton on the left, one
cut in the middle, and one cut on the right.
2. Use a vice to take out the sealing nails on the top of
the carton.
3. Open the carton.
4. Take out the middle support plate if it is included.
5. Take out the accessory package, then take out the
connecting wire (if included).
6. Lift the machine out of the carton and lay it at.
7. Remove the packing foam, and untie the packaging
bag.
Unpacking the Outdoor Unit
1. Cut the packing belt.
2. Take the unit out of the carton.
3. Remove the foam from the unit.
4. Remove the packaging bag from the unit.
Packing the Indoor Unit
1. Place the indoor unit into the packing bag.
2. Attach the packing foam to the unit.
3. Place the unit into the carton, then add the
accessory package.
4. Close the carton can seal it with packing tape.
5. Use the packing belt, if necessary.
Packing the Outdoor Unit
1. Place the outdoor unit into the packing bag.
2. Inset the packing foam into the box.
3. Place the unit into the carton, then put the upper
packing foam on the unit.
4. Close the carton and seal it with packing tape.
5. Use the packing belt, if necessary.
CAUTION
The manual button is intended for testing purposes and emergency operation only. Please do not use this
function unless the remote control is unavailable. To restore regular operation, use the remote control to
activate the unit. The unit must be turned o before manual operation.
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3.1 Installation Overview
Note: Illustrations in this manual are for explanatory purposes. The shape of your actual unit may be slightly
dierent.
1. Wall Mounting Plate
2. Front Panel
3. Louver
4. Air Filter
5. Drain Pipe (purchase separately)
6. Connection Cable (purchase
separately).
7. Refrigerant Piping (purchase
separately).
8. Remote Control
9. Remote Control Holder
(purchase separately)
10. Outdoor Unit Power Cable
(purchase separately)
Tools NOT Included:
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3.2 Installation Summary
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3.3 Installation Location
Note: Before you begin installation, refer to the label on the product box to make sure that the model number
of the indoor unit matches the model number of the outdoor unit.
The following standards will help you choose an appropriate location for the unit. Proper installation must meet
the following specications:
Do NOT install the unit in the following locations:
ǿ Near any source of heat, steam, or combustible gas.
ǿ Near ammable items such as curtains or clothing.
ǿ Near any obstacle that might block air circulation.
ǿ Near a doorway.
ǿ In a location that is subject to direct sunlight.
Note for Product Installation:
When choosing a location, be aware that you should leave ample room for a wall hole (see steps for drilling a
wall hole for connecting piping) for the signal cable and refrigerant piping that connect the indoor and outdoor
units. The default position for all piping is the right side of the indoor unit (when facing the unit).
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For R454B Refrigerant Charge Amount and Minimum Room Area:
See below for unit refrigerant specications. The indoor and outdoor units are designed to be used together.
Double check for the correct specications for your purchased unit. The indoor unit should be installed at least
6.0ft/1.8m above the oor. The height of the room cannot be less than 7.3ft/2.2m. The minimum room area of
operation or storage should be according to the table below:
Amin [ft
2
/m
2
] hinst[ft/m]
mc or mREL
[oz/kg]
6.0~7.3/
1.8~2.2
7.6/2.3 7.9/2.4 8.6/2.6 9.2/2.8 9.9/3.0
<=62.6/1.776 12/1.10
63.4/1.8 60/5.53 57/5.29 55/5.07 51/4.68 47/4.35 44/4.06
70.5/2.0 67/6.15 64/5.88 61/5.64 56/5.2 52/4.83 49/4.51
77.5/2.2 73/6.76 70/6.47 67/6.2 62/5.72 58/5.31 54/4.96
84.6/2.4 80/7.38 76/7.06 73/6.76 68/6.24 63/5.8 59/5.41
91.7/2.6 86/7.99 83/7.64 79/7.32 73/6.76 68/6.28 64/5.86
98.7/2.8 93/8.6 89/8.23 85/7.89 79/7.28 73/6.76 68/6.31
105.8/3.0 100/9.22 95/8.82 91/8.45 84/7.8 78/7.24 73/6.76
112.8/3.2 106/9.83 102/9.41 97/9.01 90/8.32 84/7.73 78/7.21
119.9/3.4 113/10.45 108/9.99 104/9.58 96/8.84 89/8.21 83/7.66
126.9/3.6 120/11.06 114/10.58 110/10.14 101/9.36 94/8.69 88/8.11
134/3.8 126/11.68 121/11.17 116/10.7 107/9.88 99/9.17 93/8.56
141.1/4.0 133/12.29 127/11.76 122/11.27 112/10.4 104/9.66 97/9.01
148.1/4.2 139/12.9 133/12.34 128/11.83 118/10.92 110/10.14 102/9.46
155.1/4.4 146/13.52 140/12.93 134/12.39 124/11.44 115/10.62 107/9.91
162.2/4.6 153/14.13 146/13.52 140/12.96 129/11.96 120/11.11 112/10.37
169.2/4.8 159/14.75 152/14.11 146/13.52 135/12.48 125/11.59 117/10.82
176.3/5.0 166/15.36 159/14.69 152/14.69 140/13 130/12.07 122/11.27
Area Formula:
Amin is the required minimum room area in ft
2
/m
2
mc is the actual refrigerant charge in the system oz/kg
mREL is the refrigerant releasable charge in oz/kg
(Applicable to the unit with the refrigerant sensor only.)
hinst is the height of the bottom of the appliance
relative to the oor of the room after installation.
WARNING
The minimum room area or minimum room area of
conditioned space is based on releasable charge and
total system refrigerant charge.
Model Indoor Unit Outdoor Unit Indoor Normal Air Volume
9K (115V) DIY-09-HP-WMAH-115D25-O DIY-09-HP-C-115D25-O 540m
3
/h 318CFM
12K (115V) DIY-12-HP-WMAH-115D25-O DIY-12-HP-C-115D25-O 540m
3
/h 318CFM
18K DIY-18-HP-WMAH-230D25-O DIY-18-HP-C-230D25-O 800m
3
/h 470CFM
23K DIY-24-HP-WMAH-230D25-O DIY-24-HP-C-230D25-O 1000m
3
/h 588CFM
36K DIY-36-HP-WMAH-230D25-O DIY-36-HP-C-230D25-O 1000m
3
/h 588CFM
When the unit detects a refrigerant leak, the minimum airow of the indoor unit is as follows:
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3.4 Drill Wall Opening
Determining Wall Opening Location
Step 1:
Remove the screw that attaches the mounting plate to
the back of the indoor unit.
Step 2:
Secure the mounting plate to the wall with the screws
provided. Ensure the mounting plate is at against the
wall.
Step 3:
Determine the location of the wall hole based on the
position of the mounting plate. The dotted rectangular
box on the right gure shows the size of your product.
NOTE
A cardboard template of the mounting plate is
included to aid in installation. It can be placed
against the wall in place of the actual mounting
plate before drilling into the wall.
9K & 12K Units
NOTE: WALL HOLE SIZE
The size of the wall hole is determined by the
connecting pipes. When the pipe size of the gas side
is Φ5/8in (Φ16mm) or more, the wall hole should be
Φ3.54in (Φ90mm). When the pipe size of the gas side
is less than Φ5/8in (Φ16mm), the wall hole should be
Φ2.5in (Φ65mm).
36K Unit
18K & 24K Units
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Drill Wall Hole
CAUTION
When drilling the wall hole, make sure to avoid wires, plumbing, and other sensitive components.
Step 2:
Place the protective wall cu in the hole. This protects
the edges of the hole and will help seal it when you
nish the installation process.
Step 1:
Using a 2.5in (65mm) or 3.54 (90mm) core drill, drill a
hole in the wall. Make sure that the hole is drilled at a
slight downward angle, so that the outdoor end of the
hole is lower than the indoor end by about 0.2-0.275in
(5-7mm). This will ensure proper water drainage.
Note for Concrete or Brick Walls:
If the wall is made of brick, concrete, or similar
material, drill 0.2in-diameter (5mm-diameter) holes in
the wall and insert the sleeve anchors provided. Then,
secure the mounting plate to the wall by tightening
the screws directly into the clip anchors.
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3.5 Refrigerant Pipe & Drain Hose Installation
NOTE
The refrigerant piping is inside an insulating sleeve
attached to the back of the unit. You must prepare
the piping before passing it through the hole in the
wall.
Tools Needed:
You will require the following tools to carry out this
installation work correctly:
• 1 open-ended spanner, 19mm
• 1 open-ended spanner, 22mm/24mm
• 1 open-ended spanner, 24mm/27mm
• 1 Allen Key, 5mm
• 1 Philips Screwdriver
• 1 leak detection spray or water/soap mixture
Important Information:
• Follow the detailed instructions for connecting the
refrigerant pipes to the indoor unit and outdoor
unit. The warranty is only valid if the lines are
installed correctly as described in the instructions.
• Do not remove the sealing caps and stoppers until
immediately before you install the lines.
• To prevent leaks, ensure that the quick-release
screw connections are absolutely free of dirt.
Moisture or foreign bodies will adversely aect the
function of the quick-release connectors, leading
to a risk of refrigerant loss, which is not covered
by the warranty.
• Only install refrigerant lines outdoors in dry
weather.
• The refrigerant lines must not be installed then
plastered over.
• Please make sure that refrigerant is never allowed
to enter the environment. Improper handling
of refrigerant may be harmful to health. Always
wear work gloves and goggles when handling
refrigerant.
• Do not smoke during the installation work. The
equipment must never be operated without
the refrigerant lines connected, otherwise the
equipment will be damaged immediately.
• The screw connections may only be tightened
using the appropriate open-ended spanner.
• Remember that if the refrigerant lines are
tightened with too little torque, they will leak, but
if they are tightened with too much torque, the
screw connections could be damaged. If you are
not condent about connecting the refrigerant
line connectors yourself, it is imperative that
you contact MRCOOL® customer service or a
refrigeration contractor.
IMPORTANT: The EQ values are only designed for
one-time installation. Their seal cannot be guaranteed
if they are installed more than once. This will also void
the warranty.
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Connect the Refrigerant Pipes to Indoor Unit
Step 1:
Do not remove the plastic seals from the indoor
equipment and the appropriate refrigerant pipe until
immediately before you connect them.
Step 2:
Align the refrigerant pipe correctly, and make sure the
dimensions of the connecting refrigerant pipe are the
same. Place the screw connector on the refrigerant
pipes onto the thread on the indoor equipment and
tighten the rst few threads by hand.
Step 3:
Using the image as a guide, and the steps
outlined in this paragraph, you will now tighten the
nuts of the screw connectors of the Quick
Connect® line set to the indoor unit. Using two
appropriate sized open-ended wrenches
(depending on the dimensions of the connector)
or adjustable crescent wrenches, place one of the
wrenches on the nut marked “1”, and the other
wrench on the nut marked “2,” as shown in the
image below. Now, turn the wrench marked “2” in
the direction of the rotational arrows, as shown,
while holding the other wrench in place. Continue
to tighten the connector until snug.
Work quickly while ensuring that the screw connectors
do not skew as you tighten them.
IMPORTANT: Since the coupling works with tapping
rings, it may leak if you disconnect and reconnect the
pipes. This will also void the warranty.
Step 4:
After nishing the connection, use the tape to wrap
the refrigerant pipe and connecting cable together.
NOTE: In North America, the cable should be
protected by an applicable conduit.
Step 5:
After connecting the quick connectors, pass the drain
hose and refrigerant pipes through the wall hole.
NOTE: The quick connector parts must be located
outside of the room. Use the wall hole sleeve, cap, and
neoprene to seal the wall hole.
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Step 6:
Use the sound-absorbent pads to prevent the quick-
connector parts from being exposed to the air. Wrap
the quick-connectors with the sound-absorbent pads
tightly.
Step 7:
Wrap the connectors with the black insulation
material. For the exposed portion on the top, use
the supplied white insulation material to wrap it up
completely.
Step 8:
Finally, use the tape to wrap the refrigerant pipe and
drain hose together. The cable should be protected by
an applicable conduit.
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Connect Drain Hose
Step 1:
The drain hose can be attached to the left or right side.
To ensure proper drainage, attach the drain hose on
the same side that the refrigerant piping exits the unit.
Attach a drain hose extension (purchased separately)
to the end of the drain hose.
• Wrap the connection point rmly with Teon tape
to ensure a good seal to prevent leaks.
• For the portion of the drain hose that will remain
indoors, wrap it with foam pipe insulation to
prevent condensation.
• Remove the air lter and pour a small amount of
water into the drain pan to ensure the water ows
from the unit smoothly.
NOTE ON DRAIN HOSE PLACEMENT
Make sure to arrange the drain hose according to
the following gures.
CORRECT
Make sure there are no
kinks or dents in the drain
hose to ensure proper
drainage.
NOT CORRECT
Kinks in the drain hose
will create water traps.
NOT CORRECT
Kinks in the drain hose will
create water traps.
NOT CORRECT
Do not place the end of
the drain hose in water
or in containers that
collect water. This will
prevent proper drainage.
PLUG THE UNUSED DRAIN HOLE
To prevent unwanted leaks you must
plug the unused drain hole with the
rubber plug provided.
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3.6 Electrical Wiring
WARNING
• Before performing any electrical work, read the following regulations.
• Before performing any electrical work, disconnect the main power to the system.
1. All wiring must comply with local and national
electrical codes, regulations, and must be
installed by a licensed electrician.
2. All electrical connections must be made according
to the Electrical Connection Diagram located on
the panels of the indoor and outdoor units.
3. 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.
4. If connecting power to xed wiring, a surge
protector and main power switch should be
installed.
5. Only connect the unit to an individual branch
circuit outlet. Do not connect another appliance
to that outlet.
6. Make sure to properly ground the unit.
7. Every wire must be rmly connected. Loose wiring
can cause the terminal to overheat, resulting in
product malfunction and possible re.
8. Do not let wires touch or rest against refrigerant
tubing, the compressor, or any moving parts
within the unit.
9. To avoid getting an electric shock, never touch
the electrical components soon 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.
WARNING
All wiring must be performed strictly in accordance
with the wiring diagram located on the back of the
indoor unit's front panel.
Connect Signal & Power Cables
The signal cable enables communication between the
indoor and outdoor units. You must rst choose the
right cable size before preparing it for connection.
NOTE: Choose the cable type according to local
electrical codes and regulations. Please choose the
right cable size according to the Minimum Circuit
Ampacity located on the nameplate of the unit.
DO NOT MIX LIVE AND NULL WIRES.
This is dangerous, and can cause the unit to
malfunction.
Connection Diagram (115V)
ConnectionDiagram(208/230V)
1. Open the front panel of the indoor unit.
2. Using a screwdriver, open the wire box cover
on the right side of the unit. This will reveal the
terminal block.
3. Facing the back of the unit, remove the large
plastic knock-out panel to create a slot through
which the conduit tube can be installed.
NOTE: For units with ve-core cable, remove the
small, middle plastic knock-out panel to create a slot
through which the cable can exit. Use needle-nose
pliers if the plastic panel is too dicult to remove by
hand.
4. As shown in the illustration, insert the wires
including the ground wire into the conduit and
secure them with a lock nut onto the conduit
mounting plate.
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26
5. Match wire colors with terminal numbers on
the indoor and outdoor unit's terminal blocks
and rmly screw the wires to the corresponding
terminals.
6. Connect the ground wires to the corresponding
terminals.
7. Pull the wires and check that the wires are
securely xed to the terminal block.
DO NOT MIX LIVE AND NULL WIRES.
This is dangerous, and can cause the unit to
malfunction.
3.7 Wrap Piping & Cables
NOTE
Before passing the piping and drain hose through
the wall hole, you must bundle them together to
save space, protect them, and insulate them.
Step 1:
Bundle the drain hose and refrigerant pipes as shown
below.
Step 2:
Using adhesive vinyl tape, attach the drain hose to the
underside of the refrigerant pipes.
Step 3:
Using insulation tape, wrap the refrigerant pipes and
drain hose tightly together. Double-check that all
items are bundled.
DRAIN HOSE MUST BE ON BOTTOM
Make sure the drain hose is at the bottom of
the bundle. Putting the drain hose at the top of
the bundle can cause the drain pan to overow,
which can lead to re or water damage.
DO NOT WRAP ENDS OF PIPING
When wrapping the bundle, keep the ends of
the piping unwrapped. You need to access them
to test for leaks at the end of the installation
process.
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3.8 Mount Indoor Unit
Put pipes in wall hole.
Hook it and press down
lightly to secure.
Check that the unit is mounted
rmly.
If you installed new connective piping to the outdoor unit, do the following:
• If you have already passed the refrigerant piping through the hole in the wall, proceed to Step 3.
1. Double-check that the ends of the refrigerant pipes are sealed to prevent dirt or foreign materials from
entering the pipes.
2. Slowly pass the wrapped bundle of refrigerant pipes, drain hose, and signal wire through the hole in the wall.
3. Hook the top of the indoor unit on the upper hook of the mounting plate.
4. Check that the unit is hooked rmly on the mounting plate by applying slight pressure to the left and right-
hand sides of the unit. The unit should not jiggle or shift.
5. Using even pressure, push down on the on the bottom half of the unit. Keep pushing down until the unit
snaps onto the hooks along the bottom of the mounting plate.
6. Again, check that the unit is rmly mounted by applying slight pressure to the left and the right-hand sides of
the unit.
If the refrigerant piping is already embedded in the wall, do the
following:
1. Hook the top of the indoor unit on the upper hook of the mounting plate.
2. Use a bracket or wedge to prop up the unit, giving you enough room to
connect the refrigerant piping, signal cable, and drain hose.
3. Connect drain hose and refrigerant piping. (Refer to the refrigerant
piping connection section of this manual for instructions.)
4. Keep pipe connection point exposed to perform the leak test. (Refer to
the Electrical Checks and Leak Checks sections of this manual.)
5. After the leak test, wrap the connection point with insulation tape.
6. Remove the bracket or wedge that is propping up the unit.
7. Using even pressure, push down on the bottom half of the unit. Keep
pushing down until the unit snaps onto the hooks along the bottom of
the mounting plate.
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NOTE: UNIT IS ADJUSTABLE
Keep in mind that the hooks on the mounting plate are smaller than the holes on the back of the unit. If you
nd that you don't have ample room to connect embedded pipes to the indoor unit, the unit can be adjusted
left or right by approximately 1.18-1.96in (30-50mm), depending on the model.
CAUTION
For the units that adopt the following pipe connectors, strictly perform the piping work in accordance with
the following instructions.
1. Before performing the refrigerant piping connection, always wear work gloves and goggles, and remember
that the connectors A and B are not allowed to face people directly.
2. Keep pressing the cross-shape part of connector B with a tool for approximately 5-10 seconds until the red
protruding point of Connector A retracts completely.
3. Remove connectors A and B, then perform the refrigerant piping connection between the indoor unit and
the outdoor unit.
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OUTDOOR UNIT INSTALLATION
4
4.1 Location Selection
NOTE: PRIOR TO INSTALLATION
Before installing the outdoor unit, you must choose an appropriate location. The following are standards that
will help you choose an appropriate location for the unit.
Proper Installation Locations Meet the Following Standards:
; Meets all spatial requirements shown in
Installation requirements above,.
; Protected from
prolonged periods of
direct sunlight or rain.
; Where snowfall is anticipated,
take appropriate measures to
prevent ice buildup & coil damage.
; Good air
circulation &
ventilation.
; Firm & solid-the
location can
support the unit
& will not vibrate.
; Noise from the
unit will not
disturb other
people.
NOTE: Install the unit by following local codes and regulations. These may dier slightly between dierent regions.
CAUTION: SPECIAL CONSIDERATIONS FOR EXTREME WEATHER
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.
Iftheunitisfrequentlyexposedtoheavyrainorsnow:
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 outdoor unit that is specially designed to resist corrosion.
DO NOT install the unit in the following locations:
ǿ Near an obstacle that will block air inlets & outlets.
ǿ Near a public street, crowded areas, or where noise
from the unit will disturb others.
ǿ In a location exposed to excessive amounts of salty air.
ǿ Near animals or plants that will be harmed by hot air
discharge.
ǿ Near any source of combustible gas.
ǿ In a location exposed to large amounts of dust.
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OUTDOOR UNIT INSTALLATION
4
4.2 Drain Joint Installation
NOTE: PRIOR TO INSTALLATION
Before bolting the outdoor unit in place, you must install the drain joint at the bottom of the unit. For the units
with base pan built-in with multiple holes for proper draining during defrost, the drain joint does not need to
be installed.
Step 1:
Find the base pan hole on the outdoor unit.
Step 2:
• Fit the rubber seal on the end of the drain joint that will connect to the outdoor unit.
• Insert the drain joint into the hole in the base pan of the unit.
• Connect a drain hose extension (not included) to the drain joint to redirect water from the unit during
heating mode.
NOTE: In cold climates, ensure that the drain hose is as vertical as possible to ensure swift water drainage. If water
drains too slowly, it can freeze in the hose and ood the unit.
mrcool.com31
4.3 Anchor Outdoor Unit
WARNING
When drilling into concrete, eye protection is recommended at all times.
• The outdoor unit can be anchored to the ground or to a wall-mounted bracket with bolts (M10). Prepare the
installation base on the unit according to the dimensions below.
• The following is a list of dierent outdoor unit sizes and the distance between their mounting feet. Prepare
the installation base of the unit according to the dimensions below.
Top View
Front View
Outdoor Unit
Model
Outdoor Unit Dimensions
W x H x D
Mounting Dimensions
Distance A Distance B
DIY-09-HP-C-115D25-O
30.1in x 21.8in x 11.9in (765mm x 555mm x 303mm) 17.8in (452mm) 11.3in (286mm)
DIY-12-HP-C-115D25-O
DIY-18-HP-C-230D25-O 35.0in x 26.5in x 13.5in (890mm x 673mm x 342mm) 26.1in (663mm) 13.9in (354mm)
DIY-24-HP-C-230D25-O
37.2in x 31.9in x 16.1in (946mm x 810mm x 410mm) 26.5in (673mm) 15.9in (403mm)
DIY-36-HP-C-230D25-O
If you will install the unit on the ground or on a
concrete platform, do the following:
1. Mark the positions for four expansion bolts based
on the dimensions chart.
2. Pre-drill holes for expansion bolts.
3. Place a nut on the end of each expansion bolt.
4. Hammer expansion bolts into the pre-drilled holes.
5. Remove the nuts from the expansion bolts, and
place the outdoor unit on the bolts.
6. Put a washer on each expansion bolt, then replace
the nuts.
7. Using a wrench, tighten each nut until snug.
If you will install the unit on a wall-mounted
bracket, do the following:
1. Mark the position of the bracket holes based on the
dimensions chart.
2. Pre-drill the holes for the expansion bolts.
3. Place a washer and nut on the end of each
expansion bolt.
4. Thread expansion bolts through holes in the
mounting brackets, put the mounting brackets in
position, and hammer expansion bolts into the
wall.
5. Check that the mounting brackets are level.
6. Carefully lift unit and place its mounting feet on the
brackets.
7. If allowed, install the unit with rubber gaskets to
reduce vibrations and noise.
CAUTION: SPECIAL CONSIDERATIONS FOR EXTREME WEATHER
Make sure that the wall is made of solid brick, concrete, or of similarly strong material. The wall must be able to
support at least four times the unit's weight.
OUTDOOR UNIT INSTALLATION
4
mrcool.com 32
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4.4 Signal & Power Cable Connection
WARNING
Before operation of the unit:
• All wiring work must be performed strictly in accordance with the wiring diagram located inside the wire
cover of the outdoor unit.
• Before performing any electrical or wiring work, turn o the main power to the system.
The outside unit's terminal block is protected by an electrical wiring cover on the side of the unit. A
comprehensive wiring diagram is printed on the inside of the wiring cover.
1. Remove the wire cover from the unit by loosening the 3 screws.
2. Connect the sheathed wire by rst turning the ring counterclockwise to remove.
3. Pass through the hole in the metal panel.
4. Reinstall the ring and tighten it by turning clockwise.
5. Replace the wire cover on the side of the unit, and screw it in place.
OUTDOOR UNIT INSTALLATION
4
mrcool.com33
4.5 Refrigerant Piping Connection
WARNING
For your safety, always wear goggles and work gloves
when connecting the pipes.
NOTE: All pictures are included for explanatory
purposes only. The actual shape of the outdoor unit
that you purchased may be slightly dierent.
Step 1:
First, remove the water tray on the outdoor unit.
NOTE: Before connecting the Quick Connect® line set, use a wrench to conrm the fast
joint and the shut-o valve are securely fastened in the direction indicated in the photo. If
there is any looseness, it needs to be tightened to prevent leakage. During the assembly
process, if there is a reverse disassembly operation, the above operation needs to be
performed to tighten it.
Step 2:
Do not remove the plastic seals from the outdoor
unit and the appropriate refrigerant pipes until
immediately before you connect them.
Step 3:
Align the refrigerant pipes correctly so that they line up
with the valves and are not stressed. Place the screw
connector on the refrigerant line just onto the thread
on the outdoor unit and tighten the rst few threads by
hand. NOTE: The refrigerant pipes must be connected
to the valves on the outdoor unit with as little stress as
possible.
WARNING
Before connecting the pipes, ensure that the quick
connectors are tightened.
Before you continue, it is essential that you read the
following instructions carefully.
OUTDOOR UNIT INSTALLATION
4
mrcool.com 34
34
Coupling Size
Pound-Force Foot
(lbf-ft)
Newton Meter (N-m)
Kilogram-Force
Meter (kgf-m)
Recommended Min.
TighteningTorque
-06 (6.35mm dash size) 18-20 24.4-27.1 2.4-2.7 10
-09 (9.62mm dash size) 30-35 40.6-47.4 4.1-4.8 15
-12 (12.7mm dash size) 45-50 61.0-67.7 6.2-6.9 25
-16 (15.88mm dash size) 60-65 81.3-88.1 8.2-8.9 32
-19 (19.05mm dash size) / / / 45
Step 4:
Using the rst image below as a guide, starting with the bottom screw connector, you will now tighten the line
set to the outdoor unit. Using two appropriate sized open-ended wrenches (depending on the dimensions of the
connector), or adjustable crescent wrenches, place one of the wrenches on the nut marked “1”, and the other
wrench on the nut marked “2,” Now, turn the wrench on nut “2” in the direction of the rotational arrow, while
holding the other wrench in place, as seen in the rst image below. Continue to tighten the connector until snug.
NOTE: Work quickly and make sure the screw connectors do not become crooked as you tighten them. Repeat
the same process for the top screw connector, using the second image below as a guide.
IMPORTANT: Since the coupling works with tapping rings, it may leak if you undo and reconnect the pipes. This
will also void the warranty.
NOTE: After completing steps 1-4, check that all the connections are sealed correctly using leak detection spray
or soap suds. If any bubbles form, the system has a leak and the screw connectors must be re-tightened using
an open-ended spanner.
Step 5:
Using the images below as a guide, remove the cover on the top valve, using a 19 mm open-ended wrench or
a crescent (adjustable-type) wrench. Then, insert a 5 mm Allen key and open the valve by turning it counter-
clockwise as far as it will go. DO NOT force it. The valve is now open. Screw the cover back onto the top valve
and tighten it well to ensure that it is properly sealed.
OUTDOOR UNIT INSTALLATION
4
mrcool.com35
POST-INSTALLATION
5
Step 6:
Using the images below as a guide, repeat the same process for the bottom valve. Remove the cover on the
bottom valve, using a 19 mm open-ended wrench or a crescent (adjustable-type) wrench. Then, insert a 5 mm
Allen key and open the valve by turning it counter-clockwise as far as it will go. DO NOT force it. Screw the cover
back onto the bottom valve and tighten it well to ensure that it is properly sealed.
IMPORTANT: The conical ring on the valve has an important sealing function together with the sealing sat in the
caps. Ensure that you do not damage the cone and that you keep the cap free of dirt and dust.
Step 7:
After completing steps 1-6, check that all the connections are sealed correctly using leak detection spray or soap
suds. If any bubbles form, the system has a leak and the screw connectors must be re-tightened.
Step 8:
Start the equipment so that the operating pressures build up inside it. Check all the connectors again for signs
of leaks during both cooling mode and heating mode. If any bubbles form, the system has a leak and the screw
connectors must be re-tightened.
5.1 Electrical & Gas Leak Checks
WARNING-RISK OF ELECTRIC SHOCK
All wiring must comply with local and national electrical codes and must be installed by a licensed electrician.
Electrical Safety Checks
After installation, conrm that all electrical wiring is installed in accordance with local and national regulations,
and according to the installation manual.
Gas Leak Checks
There are two dierent methods to check for gas leaks.
Soap & Water Method:
Using a soft brush, apply soapy water or liquid detergent to all pipe
connection points on the indoor unit and outdoor unit. The presence
of bubbles indicates a leak.
Leak Detector Method:
If using a leak detector, refer to the device's operation manual for
proper usage instructions.
AFTER PERFORMING GAS LEAK CHECKS:
After conrming that all of the pipe connection points do not
leak, replace the valve cover on the outside unit.
A: Low Pressure Stop Valve
B: High Pressure Stop Valve
C & D: Indoor Unit Flare Nuts
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36
BEFORE TEST RUN
Only perform the test run after you have completed
the following steps:
• Electrical Safety Checks - Conrm that the unit's
electrical system is safe and operating properly.
• Gas Leak Checks - Check all are nut connections
and conrm that the system is not leaking.
• Conrm that gas and liquid (high and low
pressure) valves are fully open.
5.2 Test Run
You should perform the test run for at least 30
minutes.
• Connect power to the unit.
• Press the ON/OFF button on the remote control to
turn it on.
• Press the MODE button to scroll through the
following functions, one at a time:
-Cool: Select lowest possible temperature
-Heat: Select highest possible temperature
• Let each function run for 5 minutes, and perform
the following checks:
Checks to Perform Pass/Fail
No electrical leakage
Unit is properly grounded
All electrical terminals are
properly covered
Indoor & outdoor units are
solidly installed
All pipe connection points
do not leak
Indoor (2): Outdoor (2):
Water drains properly from
drain hose
All piping is properly
insulated
Unit performs cool function
properly
Unit performs heat function
properly
Indoor unit louvers rotate
properly
Indoor unit responds to
remote control
DOUBLE-CHECK PIPE CONNECTIONS
During operation, the pressure of the refrigerant
circuit will increase. This may reveal leaks that were
not present during your initial leak check. Take
time during the Test Run to double-check that all
refrigerant pipe connection points do not have
leaks. Refer to the Gas Leak Checks section for
instructions.
After the test run is successfully completed, and you
conrm that all check points in the list have passed, do
the following:
• Using the remote control, return unit to normal
operating temperature.
• Using insulation tape, wrap the indoor refrigerant
pipe connections that you left uncovered during
the indoor unit installation process.
If Ambient Temperature is Below 60°F (16°C):
You can't use the remote control to turn on the
cool function when the ambient temperature is
below 60°F (16°C). In this instance, you can use the
MANUAL CONTROL button to test the cool function.
• Lift the front panel of the indoor unit, and raise it
until it clicks in place.
• The MANUAL CONTROL button is located on the
right-hand side of the unit. Press it 2 times to
select the COOL function.
• Perform the test run as normal.
POST-INSTALLATION
5
mrcool.com37
5.3 Care & Maintenance
CAUTION
• Clean the lter on your unit every two weeks. Failing to do so can lead to reduced cooling eciency or damage
to your health.
• Always turn o the system and disconnect its power supply before cleaning or maintenance.
• Do not touch the lter within 10 minutes after turning o the unit.
• Only use a soft, dry cloth to wipe the unit clean. You can use a cloth soaked in warm water to wipe it clean if the
unit is especially dirty.
• Do not use chemicals or chemically treated cloths to clean the unit.
• Do not use benzene, paint thinner, polishing powder, or other solvents to clean the unit. They can cause the
plastic surface to crack or deform.
• Do not use water hotter than 104°F (40°C) to clean the front panel. This can cause the panel to deform or
become discolored.
Cleaning the Air Filter
Step 1:
Lift the front panel of the indoor unit. For the unit with
a supporting rod, use it to prop up the front panel.
Step 2:
Grip the tab on the end of the lter, lift it up, then pull
it towards you and pull the lter out.
1. Flip to back 2. Remove air
freshening lter
3. Clean with
hand-held vacuum
Step 3:
If your lter has a small air freshening lter, unclip it
from the larger lter. Clean this air freshening lter
with a hand-held vacuum.
Step 4:
Clean the large air lter with warm, soapy water. Be
sure to use a mild detergent. Rinse the lter with fresh
water, then shake o excess water. Dry it in a cool, dry
place, and refrain from exposing it to direct sunlight.
Step 5:
When dry, re-clip the air freshening lter to the larger
lter, then slide it back into the indoor unit. Finally,
close the front panel of the indoor unit.
POST-INSTALLATION
5
mrcool.com 38
38
CAUTION
• Before changing the lter or cleaning, turn o the unit and disconnect its power supply.
• When removing the lter, do not touch metal parts in the unit. The metal edges are sharp.
• Do not use water to clean the inside of the indoor unit. This can destroy insulation and cause electrical shock.
• Do not expose the lter to direct sunlight when drying. This can shrink the lter.
• Any maintenance and cleaning of the outdoor unit should be performed by an authorized dealer or a licensed
service provider.
• Any unit repairs should be performed by an authorized dealer or service provider.
Maintaining the Unit
Long Periods of Non-Use
If you plan not to use the unit for an extended period
of time, do the following:
Clean all lters.
Turn on fan function
until unit dries out
completely.
Turn o the unit &
disconnect the power.
Remove batteries
from remote control.
Pre-Season Inspection
After long periods of non-use, or before periods of
frequent use, do the following:
Clean all lters.
Check for damaged
wires.
Check for leaks.
Ensure nothing is blocking the air inlets & outlets.
Replace batteries.
POST-INSTALLATION
5
mrcool.com39
CAUTION
If any of the following conditions occur, turn o the unit immediately.
• The wire is damaged or abnormally warm.
• You smell a burning odor.
• The unit emits loud or abnormal sounds.
• A power fuse blows or the circuit breaker frequently trips.
• Water or other objects fall into or out of the unit.
DO NOT ATTEMPT TO FIX THESE YOURSELF! CONTACT AN AUTHORIZED SERVICE PROVIDER IMMEDIATELY.
5.4 Troubleshooting
The following problems are not a malfunction, and in most situations will not require repairs.
Issue Possible Causes
Unit does not turn on when
pressingON/OFFbutton.
The unit has a 3-minute protection feature that prevents the unit from overloading.
The unit cannot be restarted within 3 minutes of being turned o.
TheunitchangesfromCOOL/
HEAT mode to FAN mode.
The unit may change its setting to prevent frost from forming on the unit. Once the
temperature increases, the unit will start operating in the previously selected mode
again.
The set temperature has been reached, at which point the unit turns o the
compressor. The unit will continue operating when the temperature uctuates again.
The indoor unit emits white
mist.
In humid regions, a large temperature dierence between the room's air and the
conditioned air can cause white mist.
Both the indoor and outdoor
units emit white mist.
When the unit restarts in heat mode after defrosting, white mist may be emitted due
to moisture generated from the defrosting process.
The indoor unit makes noises.
A rushing air sound may occur when the louver resets its position.
A squeaking sound may occur after running the unit in heat mode due to expansion
and contraction of the unit's plastic parts.
Both the indoor unit and the
outdoor unit make noises.
Low hissing sound during operation: this is normal and is caused by refrigerant gas
owing through both indoor and outdoor units.
Low hissing sound when the system starts, has just stopped running, or is defrosting:
This noise is normal and is caused by the refrigerant gas stopping or changing
direction.
Squeaking sound: Normal expansion and contraction of plastic and metal parts
caused by temperature changes during operation can cause squeaking noises.
The outdoor unit makes noises. The unit will make dierent sounds based on its current operating mode.
Dust is emitted from either the
indoor or outdoor unit.
The unit may accumulate dust during extended periods of non-use, which will be
emitted when the unit is turned on. This can be mitigated by covering the unit during
long periods of inactivity.
The unit emits a bad odor.
The unit may absorb odors from the environment (such as furniture, cooking,
cigarettes, etc.) which will be emitted during operation.
The unit's lters have become moldy and should be cleaned.
The fan of the outdoor unit
does not operate.
During operation, the fan speed is controlled to optimize product operation.
Operation is erratic,
unpredictable, or the unit is
unresponsive.
Interference from cell phone towers and remote boosters may cause the unit to
malfunction.
In this case, try the following:
• Disconnect the power, then reconnect.
• Press the ON/OFF button on the remote control to restart operation.
Note: If a problem persists, contact a local dealer or MRCOOL® customer service. Provide them with a detailed description of
the unit malfunction as well as your model number.
POST-INSTALLATION
5
mrcool.com 40
40
CAUTION
Before contacting a repair company, check the following points.
Problem Possible Causes Solution
Poor Cooling
Performance
Temperature setting may be higher
than ambient room temperature.
Lower the temperature setting.
The heat exchanger on the indoor or
outdoor unit is dirty.
Use the Clean function by remote control to clean the
aected heat exchanger.
Theairlterisdirty. Remove the lter and clean it according to instructions.
The air inlet or outlet of either unit is
blocked.
Turn the unit o, remove the obstruction and turn it back
on.
Doors and windows are open.
Make sure that all doors and windows are closed while
operating the unit.
Excessive heat is generated by
sunlight.
Close windows and curtains during periods of high heat
or bright sunshine.
Too many sources of heat in the room
(people, computers, electronics, etc.)
Reduce the amount of heat sources.
Low refrigerant due to leak or long-
term use.
Check for leaks, re-seal if necessary, and top o
refrigerant.
Silence function is activated (optional
function)
Silence function can lower product performance by
reducing operating frequency. Turn o Silence function.
The unit is not
working
Power failure Wait for the power to be restored.
Thepoweristurnedo. Turn on the power.
The fuse is burned out. Call a technician to replace the fuse.
Remote control batteries are dead. Replace batteries
The unit's 3-minute protection has
been activated.
Wait three minutes after restarting the unit.
Timer is activated. Turn timer o.
The unit starts and
stopsfrequently.
There's too much or too little
refrigerant in the system.
Call a technician to check for leaks and recharge the
system with refrigerant.
Incompressible gas or moisture has
entered the system.
Call a technician to evacuate and recharge the system
with refrigerant.
The compressor is broken. Call a technician to replace the compressor.
The voltage is too high or too low. Install a manostat to regulate the voltage.
Poor heating
performance
The outdoor temperature is
extremely low.
Use auxiliary heating device.
Cold air is entering through doors and
windows.
Make sure that all doors and windows are closed during
use.
Low refrigerant due to leak or long-
term use.
Call technician to check for leaks, re-seal if necessary, and
top o refrigerant.
Indicator lamps
continueashing
The unit may stop operation or continue to run safely. If the indicator lamps continue to ash or
error codes appear, wait for about 10 minutes. The problem may resolve itself.
If not, disconnect the power, then connect it again. Turn the unit on. If the problem persists,
disconnect the power and contact MRCOOL®.
Error code appears
and begins with
the following
letters in the
display area:
E(x), P(x), F(x), EH(xx),
EL(xx), EC(xx), PH(xx),
PL(xx), PC(xx)
Note: If the problem persists after performing the checks and diagnostics above, turn o the unit immediately and contact
MRCOOL®.
POST-INSTALLATION
5
mrcool.com41
POST-INSTALLATION
5
5.5 Error Display (Indoor Unit)
When the indoor unit encounters a recognized error, an error code will be displayed; the error codes are
described in the tables below:
Display Error Information Solution
DF
Defrost
Normal Display, not
error code
Cl
Active Clean
FP
Heating in Room Temperature under 46.4°F (8°C)
FC
Forced Cooling
AP
AP Mode of Wi Connection
CP
Remote Switched O
EH 00
IDU EEPROM Malfunction TS01-IDU
EH 0A
Indoor EEPROM Parameter Error TS01-IDU
EL 01
IDU & ODU Communication Error TS02-S-INV
EH 02
Zero-Crossing Signal Detection Error TS03
EH 03
IDU Fan Speed Out of Control TS04-S-IDU
EC 51
ODU EEPROM Parameter Error TS01-ODU
EC 52
ODU Coil Temperature Sensor (T3) Error TS05-ODU
EC 53
ODU Ambient Temperature Sensor (T4) Error TS05-ODU
EC 54
Comp. Discharge Temperature Sensor (TP) Error TS05-ODU
EC 56
IDU Coil Outlet Temperature Sensor (T2B) Error (Multi-Zone) TS05-ODU
EH 60
IDU Room Temperature Sensor (T1) Error TS05-IDU
EH 61
IDU Pipe Temperature (T2) Sensor Error TS05-IDU
EC 07
ODU Fan Speed Out of Control TS04-ODU
EH 0B
IDU Main Control Board & Display Board Communication Error TS07
FH CC
Refrigerant Sensor Error TS05-N10
EH C1
Refrigerant Sensor Detects Leakage TS06-N10
EH C2
Refrigerant Sensor is Out of Range & Leakage is Detected TS06-N10
EH C3
Refrigerant Sensor is Out of Range TS05-N10
EC C1
Other IDU Refrigerant Sensor Detects Leakage (Multi-Zone) TS06-N10
EL 0C
System Lacks Refrigerant TS06-INV
PC 00
ODU IPM Module Protection TS09-S
PC 01
ODU Voltage Protection TS10-S
PC 02
Compressor Top (or IPM) Temperature Protection TS11-S-INV
PC 04
Inverter Compressor Drive Error TS12-S
PC 03
Pressure Protection (low or high pressure) TS26-INV
PC 0L
Low Ambient Temperature Protection LP
----
IDUs Mode Conict (Multi-Zone) TS14
For other errors:
The display board may show a garbled code or a code
undened by the service manual. Ensure that this
code is not a temperature reading.
Troubleshooting:
Test the unit using the remote control. If the unit does
not respond to the remote, the indoor PCB requires
replacement. If the unit responds, the display board
requires replacement.
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POST-INSTALLATION
5
LEDFlashFrequency:
Display Error Information Solution
DF
Defrost
Normal display, not
error code
FC
Forced cooling
EC 51
ODU EEPROM Parameter Error TS01-ODU
EL 01
IDU & ODU Communication Error TS02-S-INV
PC 40
Communication Error between Outdoor Main Chip & Compressor-Driven Chip TS31
PC 08
ODU Overcurrent Protection TS08-S
PC 10
ODU Low AC Voltage Protection TS10-S
PC 11
ODU Main Control Board DC Bus High Voltage Protection TS10-S
PC 12
ODU Main Control Board DC Bus Low Voltage Protection/341 MCE Error TS10-S
PC 00
ODU IPM Module Protection TS09-S
PC 0F
PFC Module Protection TS30
EC 71
Over Current Failure of ODU DC Fan Motor TS04-ODU
EC 72
Lack Phase Failure of ODU DC Fan Motor TS38
EC 07
ODU Fan Speed Out of Control TS04-ODU
PC 43
ODU Compressor Lack Phase Protection TS39
PC 44
ODU Zero Speed Protection TS08-S
PC 45
ODU IR Chip Drive Failure TS40
PC 46
Compressor Speed Out of Control TS08-S
PC 49
Compressor Overcurrent Failure TS08-S
PC 30
System High Pressure Protection TS26-INV
PC 31
System Low Pressure Protection TS26-INV
PC 0a
High Temperatue Protection of Condenser TS27-INV
PC 06
Discharge Temperature Protection of Compressor TS32
LC 06
High Temperature Protection of Inverter Module (IPM) TS11-S-INV
PC 02
Compressor Top (or IPM) Temperature Protection TS11-S-INV
PH 90
High Temperature Protection of Evaporator --
PH 91
Low Temperature Protection of Evaporator --
EC 52
ODU Coil Temperature Sensor (T3) Error TS05-ODU
EC 53
ODU Ambient Temperature Sensor (T4) Error TS05-ODU
EC 54
Comp. Discharge Temperature Sensor (TP) Error TS05-ODU
EC 50
Open or Short Circuit of Outdoor Unit Temperature Sensor (T3, T4, TP) TS05-ODU
PC 0l
Low Ambient Temperature Protection LP
5.6 Error Display (Outdoor Unit with Auxiliary Board)
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POST-INSTALLATION
5
5.7 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
EH 00/
EH 0A
EL 01 EH 02 Eh 03 EH 60 EH 61 EH 0B EL 0c ec 56 fh cc
Indoor PCB
√ √ √ √ √ √ √ √
X X
Outdoor PCB
X
√
X X X X X X
√
X
Display Board
X X X X X X
√
X X X
Indoor Fan Motor
X X X
√
X X X X X X
T1 Sensor
X X X X
√
X X X X X
T2 Sensor
X X X X X
√
X
√
X X
T2B Sensor
X X X X X X X X
√
X
Refrigerant Sensor
X X X X X X X X X
√
Reactor
X
√
X X X X X X X X
Compressor
X X X X X X X X X
√
Additional Refrigerant
X X X X X X X
√
X X
PartRequiring
Replacement
Error Code
EC 53 EC 52 EC 54 EC 51 EC 07 PC 00 PC 01 PC 02 PC 03 PC 04
Outdoor PCB
√ √ √ √ √ √ √ √ √ √
Indoor Fan Motor
X X X X X X X X X X
Outdoor Fan Motor
X X X X
√ √
X
√
X
√
T3 Sensor
X
√
X X X X X X X X
T4 Sensor
√
X X X X X X X X X
TP Sensor
X X
√
X X X X X X X
Reactor
X X X X X X
√
X X X
Compressor
X X X X X
√
X X X
√
IPM Module Board
X X X X X
√ √ √
X
√
High Pressure Protector
X X X X X X X
√
X X
Low Pressure Protector
X X X X X X X X
√
X
Additional Refrigerant
X X X X X X X X
√
X
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POST-INSTALLATION
5
PartRequiringReplacement
Error Code
PC 06 PC 08/44/49 PC 0a PC of PC 40
Outdoor PCB
√ √ √ √ √
Outdoor Fan Motor
X
√ √
X X
T3 Sensor
X X
√
X X
TP Sensor
√
X X X X
Pressure Sensor
X X X X X
Reactor
X
√
X
√
X
Compressor
X X X X X
IPM Module Board
X
√
X X
√
High Pressure Valve Assembly
√
X X X X
High Pressure Protector
X X X X X
Low Pressure Protector
X X X X X
Additional Refrigerant
√
X
√
X X
Electric Control Box
X X X X
√
PartRequiringReplacement
Error Code
PC 41 PC 43 PC 10/11/12 PC 30 PC 31
Outdoor PCB
√ √ √ √ √
Outdoor Fan Motor
X X X
√
X
T3 Sensor
X X X X X
TP Sensor
X X X X X
Pressure Sensor
X X X X X
Reactor
X X
√
X X
Compressor
X
√
X X X
IPM Module Board
X X
√
X X
High Pressure Valve Assembly
X X X X X
High Pressure Protector
X X X
√
X
Low Pressure Protector
X X X X
√
Additional Refrigerant
X X X X
√
DIY
®
Series
Single-Zone
Mini-Split System
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.
