MrCool DIYCASSETTE HP-230C25 Series Operating instructions

Please read this manual carefully before installation and keep it for future reference.
Due to updates and constantly improving performance, the information and instructions within this
manual are subject to change without notice. Please visit www.mrcool.com/documentation to
ensure you have the latest version of this manual.
Version Date: 08-02-22
Installation & Owner’s
Manual
DIY®Ceiling Cassette
Model - DIYCASSETTE**HP-230C25

Contents
Page 1 mrcool.com
Safety Precautions
Warnings .......................................................................................................................................... 3
Cautions ........................................................................................................................................... 5
Cassette Overview
Parts Diagram ................................................................................................................................. 6
System Diagram ............................................................................................................................. 7
Indoor Unit Display ........................................................................................................................ 8
Accessories ........................................................................................................................................... 9
Operating Instructions
Operating Temperature ................................................................................................................ 11
Basic Operation Modes ................................................................................................................. 12
Special Features & Functions ........................................................................................................ 12
Care and Maintenance
DISCLAIMER: You are assuming risk by handling materials containing refrigerants under pressure, that
if not handled properly, can cause bodily injury. If you do not feel comfortable conducting this
installation process,we recommend you retain the services of a qualified HVAC professional.
****Electrical work must be completed by a qualified electrical technician.****
!
1
2
3
Cautions ...........................................................................................................................................
Cleaning the Unit ............................................................................................................................
Cleaning the Air Filter .....................................................................................................................
Preparation for Extended Non-Operation ...................................................................................
Preseason Inspection .................................. ...................................................................................
15
15
16
17
17
4
Indoor Unit Dimensions ..............................................................................
18
Line Set Length Specifications ....................................................................................................... 19

Contents
Electrical Connections ....................................................................................... 42
Test Run ................................................................................................................ 51
Page 2mrcool.com
Electrical and Gas Leak Checks ......................................................................... 50
Troubleshooting .................................................................................................. 53
*Pat. https://mrcool.com/mrcool-patents/
EU Disposal Guidelines ........................................................................................ 57
1. Mount Panel to Indoor Unit .................. 39
2. Connect Panel Display Board to
Indoor Main Control Board ................... 40
3. Install Wireless Controller Module ....... 40
Cassette Panel Installation .......... 39
Outdoor Unit Installation ........... 32
1. Selecting an installation location ....... 32
2. Install Drain Joint .................................. 33
3. Anchor Outdoor Unit ........................... 34
4. Connect Line Set to Outdoor Unit ...... 35
5. Open Refrigerant Valves of
Outdoor Unit ......................................... 37
6. Check Line Set Connections &
Valves for Leaks ................................... 38
Indoor Unit Installation ................20
1. Selecting an installation location ......... 20
2. Cut a Ceiling Hole Using Template ....... 22
3. Drill a Wall Hole for Connective Piping 23
4. Unwind Quick Connect®Line Set* to
necessary length ..................................... 23
5. Connect DIYPRO™ Cable to Indoor Unit 24
6. Install Cassette into Ceiling ................... 25
7. Connect Line Set to Cassette ................. 26
8. Check Line Set Connections for Leaks .. 28
9. Wrap Line Set Connections .................... 28
10. Install Water Receiver Tray .................... 28
11. Install Drainpipe & Adapter ................... 28
12. Seal Exterior Wall Hole ........................... 31
1. Connect DIYPRO™ Cable to Outdoor Unit .............................................................................. 48
Drainage Test ................................................................................................................................. 51
Water Discharge Test .................................................................................................................... 52
Common Issues ............................................................................................................................. 53
Troubleshooting ............................................................................................................................ 54
Automatic Wiring/Piping Correction Function (Multi-Zone Condenser)................................. 56
5
6
7
8
9
10
11
12

Page 3 mrcool.com
Read Before Using
Incorrect usage may cause serious damage or injury.
WARNING
CAUTION
WARNING
!
Safety Precautions
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.
This symbol indicates ignoring instructions may cause bodily injury, damage
to the unit, or other surrounding property.
This symbol indicates ignoring instructions may cause death or serious injury.
This symbol indicates that you should NEVER perform the indicated action.
DISCLAIMER: You are assuming risk by handling materials containing refrigerants under
pressure, that if not handled properly can cause bodily injury. If you do not feel comfortable
performing this installation process, we recommend you retain the services of a qualified HVAC
professional.
****ELECTRICAL WORK MUST BE COMPLETED BY A QUALIFIED ELECTRICAL TECHNICIAN****
DO NOT share the electrical circuit with other appliances. You must use an independent
power supply. An improper or insufficient power supply could cause fire or electrical shock.
DO NOT allow any substances or gases to enter the unit when connecting the refrigerant
piping. The presence of other gases or substances will lower the unit’s capacity, and may
cause abnormally high pressure during the operation cycle. This could cause an explosion
and/or injury.
DO NOT allow children to play with the air conditioner. Children should be supervised
around the unit at all times.
DO NOT insert your fingers, rods, or other objects into the air inlet or outlet. The fan within
the unit could be rotating at high speeds and could cause injury.
DO NOT use flammable sprays such as hair spray, lacquer, or paint near the unit. These
could cause fire and/or an explosion.
DO NOT operate the unit in places where it could be exposed to or near combustible gas.
Emitted gas could collect around the unit and cause an explosion.
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). Too much exposure to water can cause electrical
components to short circuit.
DO NOT expose your skin or body directly to the cool air coming from the unit for a
prolonged period of time.
DO NOT install the unit within 3 ft (1 m) of any combustible gas if the unit is equipped with an
auxiliary heater.
DO NOT operate the air conditioner with wet hands. This could cause electrical shock.
DO NOT turn on the power until the installation has been completed.

Safety Precautions
DO NOT pull the power cord to unplug the unit. Hold the plug firmly and pull it from the outlet.
Pulling directly on the cord can damage it, which could lead to fire and/or electric shock.
DO NOT modify the length of the power supply or use an extension cord to power the unit.
DO NOT open or remove the unit’s panel while the unit is powered on. Touching the unit’s
internal components while the unit is powered on could lead to electric shock or injury from
moving parts such as the fan.
DO NOT spray any liquids onto the unit or allow any liquids to drip onto the unit.
1. Installation must be performed according to the installation instructions. Improper installation
could cause water leakage, electrical shock, fire, and could void the warranty.
2. If the unit operates abnormally (emits strange noises or a burning a smell), immediately turn off the
unit and disconnect the power in order to avoid electric shock, fire, and/or injury. Call your local
dealer, or MRCOOL tech support at [phone], for further assistance.
3. In North America, service or repair must be performed in accordance with the requirements of NEC
and CEC (by authorized personnel or authority having jurisdiction only). Contact an authorized
service technician for repair or maintenance of the unit.
4. Only use the included accessories and specified parts for installation. Using non-standard parts can
cause water leakage, electrical shock, fire, and may cause the unit to fail.
5. Install the unit in a firm, stable location that can support its weight. If the installation location cannot
support the weight of the unit, it could fall and cause serious injury and/or damage.
6. Appropriate wiring standards, regulations, and the installation manual must be followed for all
electrical work.
7. If connecting power to fixed wiring, the following must be incorporated within it, in accordance with
the wiring rules; an all-pole disconnection device (which has at least 3 mm of clearances in all poles),
and have a leakage current that may exceed 10 mA, the residual current device (RCD) having a rated
residual operating current not exceeding 30 mA, all must be present.
8. For all electrical work, fuse the specified cables. Connect cables tightly and clamp them securely to
prevent external forces from damaging the terminal. Improper electrical connections could overheat,
causing fire and/or electrical shock.
9. All wiring must be properly arranged to ensure that the control board cover can close properly. If the
control board cover is not closed properly, it can lead to corrosion, which can cause the connection
points on the terminal to overheat, which could result in fire and/or electric shock.
10. In certain functional environments (such as kitchens and server rooms etc.), the use of specially
designed air-conditioning units is highly recommended.
11. If the supply cord is damaged, it must be replaced by the manufacturer, its service agent, or a similarly
qualified person in order to avoid a hazard.
12. This appliance can be used by children (8 years and older) and persons with reduced physical,
sensory or mental capabilities, or lack of experience and knowledge if they have been given
instruction concerning the use of the appliance and understand the hazards involved. Children
should not play with the appliance. Cleaning and user maintenance should not be performed by
children.
13. If the air conditioner is used together with burners or other heating devices, thoroughly ventilate
the room in order to avoid an oxygen deficiency.
14. Contact an authorized service technician for repair or maintenance of this unit.
15. Install drainage piping according to the instructions in this manual. Improper drainage may cause
water damage to your home and property.
16. When moving or relocating the air conditioner, consult experienced service technicians for
disconnection and re-installation of the unit.
WARNING
Page 4mrcool.com

Page 5
Safety Precautions
mrcool.com
NOTE ON FLUORINATED GASES:
1. This unit contains fluorinated greenhouse gases.
2. For specific information on the type of gas and the amount, please refer to the relevant label on
the unit itself.
3. Service, maintenance, and repair of this unit must be performed by a certified technician.
4. Product un-installation and recycling must be performed by a certified technician.
5. For equipment that contains fluorinated greenhouse gases in quantities of 5 tonnes of CO2
equivalent or more, but less than 50 tonnes of CO2 equivalent, and has a leak-detection system
installed, it must be checked for leaks at least every 24 months.
6. Keeping a record of all leak checks for the lifetime of the unit is strongly recommended.
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 use the device for any other purpose than its intended use.
DO NOT climb onto or place objects on top of the outdoor unit.
1. Turn off the air conditioner and disconnect the power if it is not going to be used for an
extended period of time.
2. Turn off and unplug the unit during storms.
3. Some parts of the unit are very sharp and can cause injury if touched. To prevent this, always wear
gloves when installing or servicing the unit.
4. Ensure water condensate from the unit can flow freely through the condensate drain pipe.
17. The product must be properly grounded during installation or electrical shock could occur.
18. For more information on how to install the appliance to its support, please refer to the indoor unit
installation and outdoor unit installation sections of this manual.
19. Keep the power plug clean and remove dust or grime that accumulates around the plug. A dirty plug
could cause fire or electric shock.
20. Dispose of this unit’s packaging carefully and ensure children do not play with it. The packaging for
this unit, especially plastic components, can be dangerous and can cause serious injury or death.
Screws, staples, and other metal packaging components can be sharp and can also cause injury.
21. The refrigerant in the unit is safe and should not leak if the system is installed properly. However, in
the event that a large amount of refrigerant leaks into a room, the oxygen concentration will decrease
rapidly. This can cause serious injury or death. The refrigerant is heavier than air, so the danger is
greater in basements or other underground spaces. Should a refrigerant leak occur, turn off any
devices that produce a naked flame and any heating devices (toxic fumes could be produced if
refrigerant comes in contact with them), ventilate the room, and contact your supplier or service
technician immediately.
WARNING
TAKE NOTE OF FUSE SPECIFICATIONS
The air conditioner’s circuit board (PCB) is designed with a fuse to provide over-current protection.
The specifications of the fuse are printed on the circuit board. Examples of this include,
T5A/250VAC and T10A/250VAC.

Page 6
Safety Precautions
mrcool.com
The installation must be performed in accordance with the requirement of local and national
standards. The installation may be slightly different in different areas.
NOTE ON ILLUSTRATIONS
Illustrations in this manual are for explanatory purposes. The actual shape of your unit may vary.
1
Cassette Overview
Fig. 1.1
NOTE ON INSTALLATION
Air Intake Grille
Air Filter
Air Vane
Display Panel
Air Outlet
Air Inlet
Electronic Control Box

NOTE ON INSTALLATION OF A DIY SINGLE-ZONE OR MULTI-ZONE SYSTEM
Please read this instruction manual fully before you attempt to install the cassette as part of a
single-zone or multi-zone system. There are many considerations to make installing either system.
However, because there are multiple units, pipes, and lines to be installed in different locations, and
heating/cooling zones to consider in a multi-zone system, planning your installation is extremely
important in order to help prevent any potential problems. Taking proper measurements is also vital
to determine the line set lengths needed to connect the indoor units to the outdoor unit. If you find
the standard line set length is not sufficient for your application, you may need to purchase additional
line sets and coupler kits. It should be noted that in a multi-zone system, with multiple line sets, the
line sets may need to be run to a central location, such as an attic, basement, or crawlspace, and have
them exit the house (to the outdoor unit) from that location.
Page 7
Overview - System Diagram
mrcool.com
Outdoor Unit
(Exterior/Condenser)
Indoor Unit
(Interior/Cassette)
Turbo
1
3
4
5
6
6
7
8
System Parts:
1. Air Inlet (w/filter installed)
2. Airflow louver (at air outlet)
3. Display Panel
4. Drain Pipe
5. Quick Connect®Line Set
(refrigerant pipe)*
6. Air Inlet
7. Air Outlet
8. Remote Controller
9. Outdoor Unit Power Cable
*Pat. https://mrcool.com/mrcool-patents/
Air-break switch
2
9

Overview - Indoor Unit Display
mrcool.com
Display Code Meanings
Page 8
Display Panel
The display panel of the indoor unit will look similar to illustration below.
Fig. 1.2
Will display when the electric heating function is activated (not available on this unit).
Will display when the timer is activated.
Will display when the unit is powered on.
Alarm indicator.
Will display when the Wireless Control feature is activated (some units).
Will display when preheating/defrost feature is activated.
Displays set temperature reading, operation feature, and error codes.
Will display when the heating feature is activated in a room with a temperature
under 46°F (8°C).
Will display when the Active Clean feature is activated.
Will display when WIFI module enters AP mode (some units).
Will display when forced cooling feature is activated.

Page 9
Accessories
mrcool.com
Note: Illustrations are for explanatory purposes only - The actual shape and size may vary.
The listing below shows the accessories and parts (these may vary depending on purchase
& options). Some of the parts listed as optional may be included in the packaging for the
condenser all others will need to be purchased separately. Use all of the installation parts
and accessories to install the system. Improper installation may result in water leakage,
electrical shock, fire, and/or equipment failure.
AAA Batteries 2
Cable Ties 6
Drain Pipe Adapter
(w/clamps) 1
Assembly & Installation
Hardware Kit
(Screws: ST8*50, M4*22,
ST3.9*16, ST4.8*12, ST3.9*10)
1
(8, 8, 2, 2, 3)
Water Receiver Tray 1
DIYPRO™ Cable 1
Drain Joint 1
Insulation Sleeves 2
Seal 1
Remote control 1
PART LOOKS LIKE... QUANTITY
Installation & Owner’s
Manual 1
Pleaseread this manual carefully before installation and keep it for future reference.
Owner’s Manual
One-Way Cassette
For more details visit www.MrCool.com
Cardboard Installation
Template 1
Sound Deadening
Pads 2
Cassette Panel
1

Page 10mrcool.com
Accessories
*Pat. https://mrcool.com/mrcool-patents/
QUANTITYPART LOOKS LIKE...
Wireless Controller
Module (WiFi)
Quick Connect
®
Line Set (refrigerant pipe)*
Line Set Sizes Include:
16 ft & 25 ft
Rubber Ring
(optional)
Plastic Wall Sleeve & Cap
(included with condenser)
Depends on Purchase
1
1
1
Neoprene
(included with condenser)
1
(Sealant for Wall Hole)
Note: Illustrations are for explanatory purposes only - The actual shape and size may vary. The
installation of this product, as described in this manual, may require additional items or tools to
complete the installation which need to be purchased separately. Such as the drain pipe (PVC tube
with a 3/4 in (19.05 mm) exterior diameter, length dependent on needs of application) which can be
found at a local hardware store or dealer. Please read this manual entirely and ensure you have
everything required on-hand before you begin the installation!

Page 11
Safety Precautions
mrcool.com
Operating Temperature Ranges
2
Operating Instructions
DRY Mode
HEAT Mode
COOL Mode
Room
Temperature
61°F - 90°F
(16°C - 32°C)
32°F - 122°F
(0°C - 50°C)
-13°F - 122°F
(-25°C - 50°C)
-13°F - 75°F
(-25°C - 24°C)
32°F - 86°F
(0°C - 30°C)
50°F - 90°F
(10°C - 32°C)
Outdoor
Temperature
NOTES:
• If the air conditioner operates for extended periods in cooling mode and the humidity is high
(over 80%), condensed water may drip out of the unit. If this occurs, set the airflow louver to
its maximum angle, and set it to HIGH fan mode.
• Optimum performance will be achieved within the above operating temperatures. If the air
conditioner is operated outside of the above temperatures, certain safety protection features might
be activated and cause the unit to function abnormally or disable.
Optimal Operation
To achieve optimal performance, please note the
following:
DO NOT put any objects near the air inlets &
outlets. Doing this would impair performance and
could cause the unit to shut down.
• Adjust the airflow direction of the louvers
correctly, so that it is not towards people or at an
extreme angle/closed.
• Adjust the temperature to achieve moderate
comfort levels. An excessively low or high
temperature setting wastes energy.
• Keep windows and doors closed, as this will
improve performance.
• Limit energy usage (run time) using the TIMER
function and SLEEP/ECONOMY mode if applicable.
• Inspect and clean the air filter every two weeks.
Doors and windows
should be kept
closed.
Closing the curtains
while heating also
helps keep the heat in
CAUTION
DO NOT put your fingers into the panel of the blower and suction side. The high speed fan
inside may cause injury.
The table below represent the normal temperature ranges the unit is designed to operate in. If the unit is
operated outside of these ranges, certain safety protection features could activate and cause the unit to
disable or operate abnormally.

Page 12
Operating Instructions
mrcool.com
Basic Operation Modes:
AUTO / COOL / DRY / HEAT / FAN (Model Dependent).
AUTO Mode:
When you set the unit in AUTO mode, it will automatically select COOL, HEAT, or FAN-ONLY mode
depending on the set temperature and the room temperature. The unit will control the room temperature
automatically, according to the temperature you set the unit to.
COOL Mode:
When unit is set in COOL mode, it puts the system into the cooling operation. It will continually cool the room
until the it reaches the temperature set on the display.
DRY Mode:
The temperature is regulated while dehumidifying by intermittently switching the COOL or FAN modes on and
off. The fan speed is set to LOW.
HEAT Mode:
The unit is a heat pump by design. By reversing the air conditioning process, it absorbs heat from the
outdoors and transfers it to the indoor unit. At the same time, heat loading of the air conditioner increases
due to larger differences between the indoor and outdoor temperature. As a result, the operating
performance and efficiency is reduced as the outdoor air temperature drops. If you feel that the heating
performance is insufficient, it is recommended that you supplement heating with other appliances.
FAN Mode:
When the unit is put into FAN mode, the HEAT or COOL modes are deactivated and only the fan operates.
The fan continually recirculates the air in the room.
Special Features & Functions:
SLEEP Mode:
The SLEEP function is used to decrease energy use while you sleep. During sleep you do not need the same
temperature settings to stay comfortable. This function can only be activated via the remote control. The
SLEEP function is not available in FAN or DRY modes. When SLEEP mode is activated, the temperature will
increase while cooling, or decrease while heating by, 2°F (1°C) per hour for the first 2 hours. Thereafter, it
keeps this new temperature for 6 hours before SLEEP mode will automatically switch off and return to the
original temperature before it was activated.
Set
Temperature 1hr 1hr
Continues
running
SLEEP Operation
Saving energy during sleep
Heat mode (-2°F/1°C) per hour
for the first two hours
Cool mode (+2°F/1°C) per hour
for the first two hours

Page 13
Operating Instructions
mrcool.com
Special Features & Functions (continued):
Refrigerant Leakage Detection System:
If a refrigerant leak should occur, the LED display will show a refrigerant leak error code and the LED indicator
light will flash.
Louver Angle Memory Functions (optional):
Some models are equipped with a louver angle memory function. When the unit restarts after a power failure,
the angle of the horizontal louvers will automatically to their previous position. NOTE: To reset the louver,
press the manual button, which will reset the louver settings.
Three-Minute Protection Feature:
This is a protection feature that will prevent the air conditioner from being activated for approximately 3
minutes when it is restarted immediately after being turned off. This is to prevent the compressor from being
damaged during a quick restart.
Auto-Restart:
In the event of a power interruption, such as a blackout, the unit will immediately stop. When power is
restored, the operation light on the cassette will begin to flash. To restart the unit, press the ON/OFF button
on the remote control.
• If the system has an auto restart function, the unit will restart using the settings before the
outage occurred.
• If the unit is not equipped with an auto-restart function, the system will revert back to the
factory default settings (AUTO mode, AUTO fan, and a temperature setting of 76°F (24°C)). This
may cause inconsistencies on the remote control and unit display panel. Use the remote control
to update the settings.
Active Clean Function:
This function actively washes away dust and dirt that can collect on the heat exchanger within the cassette. It
functions by operating to create more condensate (water) on the heat exchanger. Then it will automatically
freeze the condensate on the heat exchanger and rapidly thaw the frost to wash away the debris that has
collected. The fan will operate to blow out the cold air created. Once the dust and dirt have been washed
away, the fan will continue to spin to blow dry the evaporator with hot air. When this function is activated, the
letters CL will appear in the display panel. The process will take anywhere from 20 to 130 minutes to
complete. Once it is complete, the unit will automatically shut off and cancel the Active Clean function.
NOTE: During this operation a pinging sound may be heard coming from the unit.
Wireless Smart Control Function (optional):
Connect the wireless control module via the USB port inside the left access panel of the cassette. Please refer
to the Indoor Unit Installation section of this manual for more detailed instructions. This will allow the unit
to be controlled by the remote control and/or the smartphone app.
CAUTION
DO NOT set the angle of the horizontal louver too narrow, as this could cause condensation
to form and drip into the unit.
CAUTION
DO NOT stand near the air outlet of the unit while the Active Clean function is occurring. For
some units, the air outlet temperature will be very high.

Page 14
Operating Instructions
mrcool.com
Special Features & Functions (continued):
Automated Panel Drop Function:
This unit is equipped with four electric motors which raise and lower the air intake grille, which houses the air
filter. This function allows for easy access to the air intake grille and filter for cleaning or replacement if
necessary. The grille can be lowered to a maximum of 4.9 ft (1.5 m) from the ceiling cassette. Below are
instructions of how to raise and lower the panel while using the remote control. For more detailed
instructions of this operation and cleaning the filter, please refer to the Care & Maintenance section of this
manual.
Panel Drop Operation:
1.) While in stand-by mode, press and hold the MODE and DOWN buttons on the remote
control simultaneously for 3 seconds. This will allow you to enter the panel setting mode.
When this mode is accessed the remote controller will display F2.
2.) While in the panel setting mode use the UP or DOWN buttons to raise or lower the air intake
grille, respectively.
3.) Press any button to exit the panel setting mode.
Turbo
CAUTION
DO NOT allow obstacles to get in the path of the panel while it is being raised or lowered. If
the panel comes into contact with an obstruction that causes it to raise while it is being
lowered, it will stop. If the panel comes into contact with an obstruction while being raised
and is not fully retracted, it will automatically lower after a period of time and then try to
rise again. If this occurs three times an error code will display and prompt you to correct this
manually. NOTE: The unit will not function until the obstruction is removed and the panel is
fully retracted and seated in the cassette faceplate.

Page 15 mrcool.com
3
Care and Maintenance
Cleaning the Unit:
Wipe the unit with a soft dry cloth. If the unit is very dirty, clean it with a damp, lint-free cloth soaked in warm
water and neutral detergent. Dry the unit with a dry, lint-free cloth.
The power supply must be disconnected before attempting any kind or service and most
cleaning procedures (removal and cleaning of the air filter is the only exception)!
Before performing maintenance, turn the power off to the unit and then disconnect the power
to the circuit at the breaker. Failure to do this could cause electrical shock and injury.
DO NOT attempt to perform any repairs on the unit. Contact an authorized service
technician. Improper repair could cause water leakage, electrical shock, fire, and could void
the warranty.
DO NOT substitute a blown fuse with a higher or lower amperage fuse than what is specified
for your application. Using an improperly rated fuse could cause circuit damage and/or an
electrical fire.
DO NOT operate the unit or perform any maintenance if the drain hose is not installed and
set up properly according to the instructions. Failure to do this could result in leakage,
property damage, fire, and/or electric shock.
DO NOT operate the unit or perform any maintenance if the wires are not connected
properly according to the instructions. Failure to properly connect the wires could result in
electrical shock and/or fire.
CAUTION
CAUTION
DO NOT use benzene, thinner, polishing powder, or similar solvents for cleaning. These
could cause the plastic to deform and/or crack.
DO NOT clean the unit with excessive amounts of water or wash the unit under running
water, as it could create an electrical hazard.
DO NOT use a chemically treated cloth or duster to clean the unit.
DO NOT clean the unit with combustible cleaning agents. These could cause fire and/or
deformation of the unit.
DO NOT wash the front panel with water hotter than 104°F (40°C). Doing this could cause
the panel to deform or become discolored.
DO NOT use water to clean the inside of the unit. This can destroy the insulation and cause
electric shock.

Care and Maintenance
mrcool.com
Page 16
mrcool.com
Cleaning the Air Filter:
The air filter prevents dust and other particles from entering the indoor unit. Dust buildup can reduce the
efficiency of the unit. For optimum efficiency, clean the air filter every two weeks. If you live in a dusty area, it
may be necessary to clean the filter more frequently. In the event the air filter is heavily clogged and cannot
be cleaned, it is recommended to replace it with a new one.
Directions to Access, Remove, & Clean the Air Filter
1. The air filter of the cassette is located inside the air
intake grille of the unit. In order to gain access to the
filter, you will have to lower the air intake grille using
the remote control.
2. With the unit in stand-by mode, press and hold the
MODE & DOWN buttons simultaneously for 3 seconds.
This will allow you to enter the panel setting mode.
The remote control should display F2.
3. Then, press the DOWN button on the remote control.
The air intake grille will automatically start lowering.
Wait until it stops before attempting to remove the
air filter (Refer to Fig. 3,1).
4. Remove the filter from the air intake grille by following
these steps (Refer to Fig. 3.2):
a. Hold the upper edge of the filter with both hands
and gently lift upward until the upper edge is free
from the air intake grille lowering cables.
b. Lift the filter and move it forward slightly until the
filter screen is separated from all four lowering
cables.
c. Move the filter to the right until it is separated from
the air grille. Then it can be taken out for cleaning.
5. The air filter can be cleaned by using a vacuum cleaner
or rinsing it with water (Refer to Fig. 3.3).
a. If using a vacuum cleaner, ensure the air intake
side of the filter is face up, as that is the side that
will trap the dust and debris.
b. If rinsing the filter with water, ensure the air intake
side of the filter is facing down and the water runs
on the back side. This will effectively rinse the dust
and debris from the filter.
6. Reinstall the filter by reversing step 4.
7. Press the UP button on the remote control to raise the
air intake grille back into place.
NOTE: In households that have pets or other animals, it will be necessary to periodically wipe down
the air intake grille on the unit to remove any animal hair that could block or restrict airflow.
CAUTION
DO NOT expose the filter to direct sunlight when allowing it to dry. This could cause the
filter to shrink.
DO NOT attempt to dry out the filter with fire or any other heat source.
DO NOT touch the metal parts of the unit when removing the filter. The sharp edges could
cut you.
a
b
c
NOTE: For filters that have collected excessive
amounts of dust, it may be necessary to use a soft
brush and neutral detergent to gently brush it
away. Once clean, allow to dry in a cool place.
Fig. 3.1
Fig. 3.2
Fig. 3.3

Page 17
Care and Maintenance
mrcool.com
Preparation for Extended Non-Operation:
If you plan to not run the unit for an extended period of time (e.g. from the end of summer to the beginning of
the following summer), perform the following:
1. Clean the indoor unit and filters as outlined in the previous steps.
2. Operate the unit in FAN-Only mode for at least 8 hours to dry out the inside of the unit.
3. Turn off the unit. Then, turn off the power to the circuit at the breaker. The unit should be the only
appliance on this circuit.
4. Remove the batteries from the remote control.
5. The outdoor unit also requires periodic maintenance. However, it is highly recommended you contact a
qualified service professional to perform this. Please DO NOT attempt to do this on your own.
Pre-Season Inspection:
After prolonged non-operation perform the following:
1. Use a dry cloth to wipe off any dust that has accumulated on the air intake grille. This will avoid any dust
from being dispersed from the indoor unit.
2. Check for any damaged or disconnected wires.
3. Clean or replace the filters and ensure they are properly installed.
4. Check for water and oil leaks.
5. Check for blockages in the airflow inlet and outlet.
6. Replace batteries in the remote control.
Check for damaged
wires Check for leaks
Make sure no obstructions are blocking air inlets and outlets
Clean all filters
Clean all filters Turn on FAN function
until unit dries out
completely
Turn off the unit
and disconnect
the power

Page 18
mrcool.com
4
Indoor Unit Dimensions
18.7 in (475 mm)
8.07 in (205 mm)
9.84 in
(250 mm)
53.54 in (1360 mm)53.54 in (1360 mm)
16.65 in (423 mm)
13.19 in (335 mm)
43.5 in (1105 mm)
Fig. 4.1 Face Plate (bottom view when installed in ceiling)
Fig. 4.2 Side View
Fig. 4.3 Front View

Page 19
Line Set Length Specifications
mrcool.com
18K
2-Zone
Condenser
27K
3-Zone
Condenser
Maximum combined line set
length for all rooms
123 ft
(37.5 m)
172.2 ft
(52.5 m)
Maximum line set length
for one indoor unit
73.8 ft
(22.5 m)
73.8 ft
(22.5 m)
Maximum height difference
between indoor & outdoor unit
33 ft
(10 m)
33 ft
(10 m)
Maximum height difference
between indoor units
33 ft
(10 m)
33 ft
(10 m)
36K
4-Zone
Condenser
48K
5-Zone
Condenser
221.5 ft
(67.5 m)
73.8 ft
(22.5 m)
73.8 ft
(22.5 m)
221.5 ft
(67.5 m)
33 ft
(10 m)
49.2 ft
(15 m)
33 ft
(10 m)
33 ft
(10 m)
Line Set Length & Height Specifications
When installing the ceiling cassette as part of a single-zone (18K capacity cassette & condenser only) or
multi-zone system (9K, 12K, & 18K capacity cassettes can be used with multi-zone condensers), ensure that
the length of the refrigerant pipe and the drop height between the indoor and outdoor units meet the
requirements listed in the tables below:
Units: feet (meters)
18K
Single-Zone Condenser
Maximum line set length
System Capacity
Condenser Capacity
98 ft
(30 m)
Maximum height difference
between indoor & outdoor unit
66 ft
(20 m)
Maximum Line Set Length and Height Specications
18K Ceiling Cassette & 18K Single Zone Condenser
9K, 12K, & 18K Ceiling Cassette when used with a Multi-Zone Condenser
The tables below represents the maximum length and height that the refrigerant line sets can be for each
system based on its respective capacity. In order to achieve some of these lengths, if needed for your
application, line set coupler kits and additional line sets must be used (not included, sold separately). Any
attempt to increase the line set length beyond what is specified in these tables, could result in reduced
heating/cooling performance, system damage or failure, and WILL VOID THE WARRANTY.
IMPORTANT!
Units: feet (meters)