Mitsubishi Electric Ceiling Suspended Air Conditioner Installation Manual

Safety Precautions

WARNING: Indicates that incorrect installation may cause serious consequences, including death or injury.

CAUTION: Indicates that incorrect installation may cause serious consequences depending on the circumstances.

Always follow the instructions provided. Marks indicate actions to be taken or avoided:

• Never do it under any circumstances.
• Always do it according to the instruction.

After installation, perform commissioning, explain operation and maintenance to the customer, and ensure they keep the user's manual.

General Warnings:

• Perform earth wiring securely. Do not connect to gas pipes, water pipes, or lightning rods.
• Install an earth leakage breaker.
• Use a circuit breaker of the correct capacity.
• Do not use fuses of incorrect capacity or bypass them with wire.
• Do not install near flammable gas leakages.
• Do not install or use in environments with corrosive or flammable gases, or volatile flammable substances.
• Ensure adequate space for installation, inspection, and maintenance.
• Do not use the unit where water splashes.
• Do not use for special purposes like food storage or preservation of animals/plants.
• Avoid installation near equipment generating electromagnetic waves or high harmonics.
• Do not install the remote control in direct sunlight.
• Installation must be performed by a specialist.
• Install the system correctly according to the manuals.
• In small rooms, take measures to prevent exceeding refrigerant density limits.

Installation Location Precautions:

• Do not install in places where flammable gas could leak.
• Do not install in places where carbon fiber, metal powder, or other powders are present.
• Do not install where substances affecting the air conditioner are generated (sulfide gas, chloride gas, etc.).
• Do not install in places where cosmetics or special sprays are frequently used.
• Do not install in highly salted areas like beaches.
• Do not install in heavy snow areas.
• Do not install in places exposed to oil mist or steam directly.
• Do not install in places affected by smoke from a chimney.
• Do not install at altitudes over 1000m.
• Do not install in places where machinery generating high harmonics is used.
• Do not install the indoor unit in locations with obstacles preventing air inlet/outlet.
• Do not install the motion sensor in places that could cause detection errors.
• Do not install in locations where vibration can be amplified.
• Do not install where the infrared receiver is exposed to direct sunlight or strong light beams.
• Do not install where static electricity or electromagnetic waves generate.
• Do not install where equipment affected by high harmonics is placed (e.g., TV/radio within 5m).
• Do not install in places exposed to high temperature or humidity for long periods.
• Do not install in dusty places or where the lens face could be fouled or damaged.
• Do not install the outdoor unit where insects or small animals might nest.

Installation Procedures:

• Install the unit in a location that can hold its weight.
• Install the unit properly to withstand strong winds and earthquakes.
• Do not mix air into the cooling cycle during installation or removal.
• Use genuine accessories and specified parts.
• Ventilate the working area well if refrigerant leaks.
• Carry the unit with two people if it is heavier than 20kg. Use grabbing places and protective gloves.
• Dispose of packaging material properly.
• Do not repair by yourself; consult the dealer.
• Consult the dealer or a specialist for removal.
• Do not operate the system without the air filter.
• Do not touch any button with wet hands.
• Turn off the power source during servicing or inspection.
• Do not touch refrigerant piping with bare hands during operation.
• Do not run the unit with panels or guards removed.
• Do not clean the air conditioner with water.
• Do not turn off the power source immediately after stopping operation; wait for more than 5 minutes.
• Shut off the power before electrical wiring work.
• Do not control operation with the circuit breaker.

Preparation Before Installation

Before Installation: Confirm unit type, power source specification, pipes, wires, small parts, and accessories.

Selection of Installation Location:

• Choose areas where the unit can deliver hot and cold air sufficiently.
• Suggest a circulator for ceiling heights over 3m.
• For motion sensors, installation height should be no higher than 4m.
• Ensure enough space for installation and servicing.
• Ensure proper drainage and descending slope for the drain pipe.
• Ensure no obstruction to air flow at the return grille and supply port.
• Ensure the fire alarm will not be accidentally activated.
• Prevent short-circuiting of supply air.
• Avoid areas influenced by draft air.
• Avoid direct sunlight.
• Ensure dew point is lower than 28°C and relative humidity is lower than 80%. Consider additional insulation if conditions are more severe.
• Keep TV and radio more than 1m away to avoid jamming.
• Ensure no items that can be damaged by water are placed below the unit.
• Avoid areas influenced by heat from cookware.
• Avoid areas with oil mist, powder, or steam.
• Ensure lighting devices do not affect operation, especially for wireless remote controls.
• Check if the installation location can hold the unit's weight; reinforce if necessary.
• Keep wireless units more than 6m apart to avoid cross-communication.
• Keep multiple indoor units more than 4m apart.
• Ensure adequate installation space (recommended 4000mm or more).
• Install the indoor unit at a height of more than 2.5m above the floor.

Preparation Before Installation:

• Prepare suspension bolts, nuts, and spring washers (M10).
• For grid ceilings, apply earthquake resistant brace if suspension bolt length exceeds 500mm or ceiling-roof gap exceeds 700mm.
• For direct slab installation, apply brace if bolt length exceeds 1000mm.
• Move the unit box as close to the installation area as possible.
• If unpacking, wrap the unit with a nylon sling and avoid damaging it. Do not hold fragile plastic parts.
• If laying the unit on the floor, place it with the intake grille facing upward.
• Remove the air return grille by sliding stoppers and pulling out pins.
• Remove the side panel by detaching the screw and sliding.
• Remove the hanging plate by unscrewing fixing bolts.

Installation of Indoor Unit

WARNING: Completely seal the hole in the wall with putty to prevent dust, insects, or humid air from entering, which could cause fire.

CAUTION: Seal the hole with putty to prevent water leakage or condensation damage to furniture.

1. Select suspension bolt locations and pipe hole location using the provided paper pattern and direct measurements.
2. Install suspension bolts in place.
3. Fix with 4 suspension bolts, ensuring correct length.
4. Fasten the hanging plate onto the suspension bolts, using double nuts for secure fastening.
5. Install the unit to the hanging plate by sliding it from the front and fastening the fixing bolts (M8) and screws (M4).
6. Ensure the unit is installed with a descending slope toward the drain outlet for smooth drain flow.
7. WARNING: Hang the side panel from the panel side to the rear side and fasten securely with screws.
8. CAUTION: Do not create a reversed slope, which may cause water leaks.

Refrigerant Pipe

Caution: Use new pipes and the provided flare nut. Refer to the outdoor unit manual for reusing existing pipes.

• When reusing pipes, refabricate the flare part for R32.
• Use phosphorus deoxidized copper alloy seamless pipe (C1220T) without damage or contaminants.
• Do not use refrigerants other than R32 or R410A.
• Store copper pipes indoors and seal both ends until brazing.
• Use special tools for R32 or R410A refrigerant.

Work Procedure:

1. Remove the flare nut and blind flanges on the indoor unit pipe. Use a double spanner method to avoid stressing the copper pipe.
2. Make a flare on the liquid and gas pipes and connect the refrigeration pipes. Seal gaps with putty. Maintain a bend radius of 4D or larger. Use provided flare nuts.
3. Tighten flare nuts using a torque wrench to the specified torque.
4. Cover the flare connection with insulation material and tighten with straps. Ensure complete insulation of gas and liquid pipes. Use heat-resistant insulation (120°C or more) for gas pipes. Reinforce insulation in humid conditions.
5. Refrigerant is charged in the outdoor unit. Refer to the outdoor unit manual for additional refrigerant charging.

Caution: Do not apply refrigerating machine oil to the threads of the union or the external surface of the flare. Oil may be applied to the internal surface of the flare only.

Pipes can be connected from the back, right, or top. Adjustments may be needed for different routing.

Drain Pipe

Caution: Install the drain pipe correctly to ensure proper drainage and prevent indoor flooding.

• Do not connect the drain pipe to ditches with toxic gas.
• Connect pipes securely to avoid water leakage.
• Insulate the pipe properly to prevent condensation.
• Check for proper water flow from the drain outlet and the end of the pipe.
• Ensure a descending slope of greater than 1/100, avoid up-down bends and traps, and do not install air vents.

Work Procedure:

1. Insert the drain hose completely into the base and tighten the clamp.
2. Fix the drain hose at the lowest point with a hose clamp, ensuring a gradient.
3. Connect VP20 pipe (prepared on site) to the drain hose.
4. Ensure the drain pipe has a downhill slope (more than 1/100), no traps, and no air vents.
5. Insulate the drain pipe, including the hose clamp, to prevent condensation.

Drain Test: After installation, ensure the drain system works correctly and check for water leakage.

Wiring-out Position and Wiring Connection

Electrical installation work must be performed by a qualified installer according to local regulations.

• Use an exclusive circuit.
• Use specified cords, fasten wiring securely, and avoid applying stress to terminals.
• Do not run power source and signal lines on the same route.
• Perform D type earth work.
• Refer to the electrical wiring work manual for details.

Work Procedure:

1. Remove wiring from clips.
2. Remove the control box screws.
3. Slide the control box out.
4. Remove the control box lid screws.
5. Connect each wiring to the terminal block securely.
6. Fix the wiring with a clamp.
7. Install the control box lid.
8. Return the control box to its original place.
9. Install removed parts.

Note: Wiring for wireless kits and motion sensors are pre-connected. Consult manuals for specific kit installations.

Control Mode Switching:

Switch SW8-4 can be used to switch between indoor unit silent mode (ON) and normal operation (OFF).

Attaching the Air Return Grille:

Attach the air return grille after electrical cabling work is completed. Fix the chains to the indoor unit with screws and close the grille.

Check List After Installation

Verify the following items after completing all installation work:

• Indoor and outdoor units are fixed securely.
• Leakage inspection is done.
• Insulation work is properly done.
• Water is drained properly.
• Power source voltage matches the model nameplate.
• No mis-wiring or mis-connection of piping.
• Earth wiring is connected properly.
• Cable size complies with specified size.
• No obstacles block air flow on the air inlet and outlet.