MITSUBISHI ELECTRIC MSZ-EX15NLS (01) PDF DOCUMENT

The following tools are required for the installation of the MITSUBISHI ELECTRIC MSZ-EX15NLS:

Phillips head screwdriver	5/32 inch (4 mm) hexagonal wrench
Level	Flare tool for R410A/R454B
Scale	Gauge manifold for R410A/R454B
Utility knife or scissors	Vacuum pump for R410A/R454B
3 inches (75 mm) hole saw	Charge hose for R410A/R454B
Torque wrench	Pipe cutter with reamer
Wrench (or spanner)

WARNING (Risk of fire) A2L	This unit uses a flammable refrigerant. If refrigerant leaks and comes in contact with fire or heating part, it will create harmful gas and there is risk of fire.
[Book Icon]	Read the OPERATING INSTRUCTIONS carefully before operation.
[Tool Icon]	Service personnel are required to carefully read the OPERATING INSTRUCTIONS and INSTALLATION MANUAL before operation.
i [Information Icon]	Further information is available in the OPERATING INSTRUCTIONS, INSTALLATION MANUAL, and the like.

The following warnings must be observed for safety during the installation of the MITSUBISHI ELECTRIC MSZ-EX15NLS. Failure to comply could lead to death or serious injury.

General Installation:

• Do not install the unit by yourself (user). Improper installation could cause fire, electric shock, injury, or water leakage. Consult a qualified installer.

• Follow the instructions detailed in the installation manual.

• When installing the unit, use appropriate protective equipment and tools for safety.

• Install the unit securely in a place that can bear its weight. If the location cannot bear the weight, the unit could fall, causing injury.

• Do not alter the unit, as it may cause fire, electric shock, injury, or water leakage.

• Use the parts provided or specified parts for the installation work. Defective parts could cause injury, water leakage, fire, or electric shock.

• The appliance shall be stored in a room without continuously operating ignition sources (e.g., open flames, an operating gas appliance, or an operating electric heater).

• Do not pierce or burn the unit.

• When using a gas burner or other flame-producing equipment, completely remove all refrigerant from the air conditioner and ensure the area is well-ventilated.

Electrical Safety:

• Perform electrical work according to the installation manual and use an exclusive circuit. Do not connect other appliances to the circuit.

• Ground the unit correctly. Do not connect the ground wire to a gas pipe, water pipe, lightning rod, or telephone ground.

• Do not damage the wires, as this could cause a fire.

• Shut off the main power when setting up the indoor P.C. board or wiring.

• Use the specified wires to securely connect the indoor and outdoor units. Attach wires firmly to the terminal block to avoid applying stress.

• Do not use an intermediate connection of the power cord or an extension cord. Do not connect many devices to one AC outlet.

• When plugging in the power supply plug, ensure there is no dust, blockage, or loose parts in the outlet or on the plug. Verify the plug is completely inserted.

• Securely attach the electrical cover to the indoor unit and the service panel to the outdoor unit to prevent dust and water collection.

• Install the unit according to national wiring regulations.

Refrigerant Safety (R454B):

• Make sure that no substance other than the specified refrigerant (R454B) enters the refrigerant circuit. Foreign substances like air can cause abnormal pressure rise, leading to explosion or injury.

• Do not discharge refrigerant into the atmosphere. Check for leaks after installation is complete. If refrigerant leaks, ventilate the room.

• Use appropriate tools and piping materials for installation, as the pressure of R454B is 1.6 times higher than R22.

• When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes to prevent air from being drawn in.

• When installing the unit, securely connect the refrigerant pipes before starting the compressor.

• Fasten a flare nut with a torque wrench as specified in the manual. Over-tightening can cause breakage and refrigerant leakage.

• Pipe-work shall be protected from physical damage and be in compliance with national and local codes and standards. The installation of pipe-work shall be kept to a minimum.

• Do not remove the RED MARKING near the pipe connection part.

To prevent serious injury when operated incorrectly, follow these cautions:

• Depending on the installation area, install a Ground Fault Interrupt (GFI) circuit breaker to prevent electric shock.

• Perform the drainage/piping work securely according to the installation manual to prevent water from dripping from the unit and damaging household items.

• Do not touch the air inlet or the aluminum fins of the outdoor unit, as this could cause injury.

• Wear protective equipment when touching the base of the outdoor unit to avoid injury.

• Do not install the outdoor unit where small animals may live. If animals enter and damage electrical parts, it could cause a malfunction, smoke, or fire. Keep the area around the unit clean.

The mounting height of the indoor unit should be 5.9 feet (1.8 m) or more from the floor, with up to 7.5 feet (2.3 m) being recommended. The unit must be installed in a room that exceeds the minimum room area (Amin) determined by the total refrigerant amount (M).

SYSTEM WITHOUT BRANCH BOX

M [kg]	Amin [m²]	Amin [ft²]
0.5	1.9	20
0.6	2.3	24
0.7	2.6	28
0.8	3.0	32
0.9	3.4	36
1.0	3.8	40
1.1	4.1	44
1.2	4.5	48
1.3	4.9	52
1.4	5.2	56
1.5	5.6	60
1.6	6.0	64
1.7	6.3	68
1.8	6.8	73
1.9	7.2	77
2.0	7.6	81
2.1	7.9	85
2.2	8.3	89
2.3	8.7	93
2.4	9.1	97
2.5	9.4	102
2.6	9.8	106
2.7	10.2	110
2.8	10.6	114

Choose a location:

• Where airflow is not blocked.

• Where cool (or warm) air spreads over the entire room.

• On a rigid wall to reduce the possibility of vibration.

• Where it is not exposed to direct sunlight.

• Where it can be easily drained.

• At least 3 feet (1 m) away from a TV and radio.

• As far away as possible from fluorescent and incandescent lights.

• Where the air filter can be easily removed and replaced.

• Away from other heat or steam sources.

Place the remote controller:

• Where it is convenient to operate and easily visible.

• Where children cannot easily touch it.

• Select a position about 4 feet (1.2 m) above the floor. Check that signals from the remote controller are received by the indoor unit. When the remote controller holder is supplied, install it at a position from which the indoor unit can receive signals.

Note: In rooms with inverter-type fluorescent lamps, the signal from the wireless remote controller may not be received.

Electrical Specifications

MODEL	MSZ-EX09NL, MSZ-EX12NL, MSZ-EX15NL, MSZ-EX18NL
INDOOR UNIT
Power supply (V, PHASE, Hz)	208/230, 1, 60
Minches Circuit Ampacity (A)	1.0
Fan motor (F.L.A.) (A)	0.67

Refrigerant Pipes Specifications

To prevent condensation, insulate the two refrigerant pipes using heat-resistant foam plastic with a 0.045 specific gravity.

Pipe	Outside diameter inch (mm)	Minimum wall thickness inch (mm)	Insulation thickness inch (mm)
For liquid	1/4 (6.35)	0.0315 (0.8)	5/16 (8)
For gas	3/8 (9.52)	0.0315 (0.8)	5/16 (8)
	1/2 (12.7)	0.0315 (0.8)	5/16 (8)

Additional Piping Notes:

• Be sure to use insulation of the specified thickness. Excessive insulation may cause incorrect installation, and too little insulation may cause condensation.

• The refrigerant pipe bending radius must be 4 inches (100 mm) or more.

• The unit has flared connections on both indoor and outdoor sides.

Attaching the Installation Plate:

1. Find a stud in the wall to attach the installation plate (1) horizontally.

2. Tighten the fixing screws (2) firmly in the holes indicated in the illustration to prevent vibration. Additional screws may be used for added support.

3. If the knockout is removed, apply vinyl tape to the edges to prevent damaging wires.

Drilling the Wall Hole:

1. Determine the hole location on the wall based on the installation plate dimensions.

2. Drill a ø 3 inches (75 mm) hole. The outdoor side should be 6/32 to 9/32 inch (5 to 7 mm) lower than the indoor side to ensure proper drainage.

3. Insert the wall hole sleeve (C).

Follow these steps to connect the wiring for the indoor unit. Note: When the indoor unit is powered from the outdoor unit, a disconnect switch may need to be installed depending on local codes.

1. Remove the panel assembly.

2. Place the upper part of the indoor unit on the installation plate.

3. Remove corner box R and the electrical cover.

4. Remove the display P.C. board holder, conduit cover, and conduit plate.

5. Attach the appropriate joint (straight joint for rear piping or elbow joint for right, left, or downward piping) to the conduit plate with a lock nut. The thread of the joint appearing inside should be less than 3/8 inch (10 mm).

6. Process the end of the ground wire (make it slightly longer than other wires) and connect it to the ground terminal of the electrical parts box.

7. Process the end of the indoor/outdoor unit connecting wire (A) and attach it to the terminal block. Ensure there is no mis-wiring and that the wire core cannot be seen.

8. Firmly tighten the terminal screws and verify the wires are securely fastened.

9. Reinstall the conduit plate, conduit cover, and display P.C. board holder.

10. According to the piping direction, remove the shaded part of the corner box L or corner box R. Reinstall the electrical cover, corner box, and front panel.

Pipe Forming General Instructions:

• Place the drain hose below the refrigerant piping.

• Ensure the drain hose is not crowded or bent.

• Do not pull the hose when applying tape.

• When the drain hose passes through the room, wrap it with insulation material (field-supplied).

For Left or Left-Rear Piping:

1. Place the refrigerant piping and drain hose together, then firmly apply felt tape (4) from the end.

2. Pull out the drain cap at the back right of the indoor unit.

3. Pull out the drain hose at the back left of the indoor unit.

4. Put the drain cap into the section where the drain hose was, at the rear of the indoor unit. Insert it fully into the drain pan.

5. Insert the drain hose fully into the drain pan at the back right of the indoor unit, checking that it is hooked securely.

6. Insert the drain hose into the wall hole sleeve (C) and attach the upper part of the indoor unit to the installation plate. Shift the unit to the left to make placing the piping easier.

7. Use cardboard spacers from the shipping box to lift the indoor unit for easier access.

8. Connect the refrigerant piping with the extension pipe (B).

9. Attach the lower part of the indoor unit into the installation plate (1).

For Rear or Bottom Piping:

1. Put the refrigerant piping and drain hose together, then apply piping tape (G).

2. Insert the piping and drain hose into the wall hole sleeve (C) and hook the upper part of the unit on the installation plate.

3. Check that the unit is hooked securely by moving it left and right.

4. Thrust the lower part of the unit into the installation plate.

Drain Piping:

• The drain hose should point downward for easy drainage.

• If the provided drain hose is too short, connect it with a field-supplied drain hose (I).

• When connecting to a hard vinyl chloride pipe, insert it securely.

• Do not make drain piping as shown in the “Do not make drain piping as shown below” section of the manual to avoid water leakage.

1. Cut the copper pipe as straight as possible with a pipe cutter.

2. Remove all burrs from the cut section of the pipe, ensuring no metal shavings get into the piping.

3. Remove flare nuts from the indoor and outdoor units and put them on the pipe.

4. Perform the flaring work. Firmly hold the copper pipe in the dimension shown in the table below. Select dimension ‘A’ from the table according to the tool you use.

5. Check the flared work. If it is defective (tilted, uneven, burred), cut off the section and repeat the procedure. The inside should be shining without any scratches and the length should be even all around.

Flaring Dimensions and Tightening Torque

Pipe diameter inch (mm)	B inch (mm)	A inches (mm)			Tightening torque
		Clutch type tool for R410A/R454B	Clutch type tool for R22	Wing nut type tool for R22	ft-lb (kgf.cm)	N•m
ø 1/4 (6.35)	21/32 (17)	0 to 0.02 (0 to 0.5)	0.04 to 0.06 (1.0 to 1.5)	0.06 to 0.08 (1.5 to 2.0)	10 to 13 (140 to 180)	13.7 to 17.7
ø 3/8 (9.52)	7/8 (22)			0.08 to 0.10 (2.0 to 2.5)	25 to 30 (350 to 420)	34.3 to 41.2
ø 1/2 (12.7)	1-1/32 (26)				36 to 42 (500 to 575)	49.0 to 56.4
ø 5/8 (15.88)	1-5/32 (29)				54 to 58 (750 to 800)	73.5 to 78.4

Pipe Connection:

• Fasten the flare nut with a torque wrench to the specifications in the table above. Over-tightening may cause the nut to break.

• For the indoor unit, connect both liquid and gas piping. First, align the center, then tighten the first 3 to 4 turns of the flare nut by hand. Use two wrenches to tighten to the specified torque.

• For the outdoor unit, connect pipes to the stop valve pipe joint following the same procedure.

Refrigerant Pipe Airtight Test:

1. Connect testing tools. Ensure stop valves are closed. Add pressure through the service port of the GAS stop valve.

2. Pressurize to 601 psig (4.15 MPa) slowly. Measure the surrounding temperature and refrigerant pressure.

3. If the pressure holds for about one day without decreasing, the pipes have passed the test. Note that a temperature change of 1°F (0.5°C) will change the pressure by about 1 psig (0.007 MPa).

4. If the pressure decreases, there is a gas leak. Find and repair the source of the leak.

Insulation and Taping:

1. Cover piping joints with a pipe cover.

2. For the outdoor unit side, insulate all piping, including the valves.

3. Apply piping tape (G) starting from the connection on the outdoor unit. Use additional insulation for piping that passes through areas with high temperature and humidity to prevent condensation.

1. Insert the power supply plug into the power outlet and/or turn on the breaker.

2. Press the Emergency Operation Switch (E.O. SW) once for COOL operation, and twice for HEAT operation. The test run will last for 30 minutes. If the left lamp of the operation indicator blinks every 0.5 seconds, inspect the indoor/outdoor unit connecting wire for mis-wiring. After the test run, emergency mode (set temperature 75°F [24°C]) will start.

3. To stop the operation, press the E.O. SW several times until all LED lamps turn off.

To check the remote (infrared) signal reception, press the OFF/ON button on the remote controller and listen for an audible indicator from the indoor unit. Press the OFF/ON button again to turn the air conditioner off.

The MITSUBISHI ELECTRIC MSZ-EX15NLS is equipped with an auto restart function. When the power supply is cut off during operation (e.g., during a blackout), the function automatically starts operation in the previous setting once the power supply is resumed. If this function is unnecessary, it can be deactivated by a service representative.

When working on the refrigerant circuit for repairs or other purposes, best practices for flammable refrigerants must be followed.

Removal and Evacuation Procedure:

1. Remove refrigerant.

2. Purge the circuit with inert gas.

3. Evacuate.

4. Purge again with inert gas.

5. Open the circuit by cutting or brazing.

The refrigerant charge must be recovered into the correct recovery cylinders. The system shall be “flushed” with OFN (Oxygen-Free Nitrogen) to render the unit safe. Compressed air or oxygen must not be used for purging.

Recovery Procedure:

When removing refrigerant, it is recommended good practice that all refrigerants are removed safely. Use only appropriate, designated, and labeled refrigerant recovery cylinders. Ensure cylinders are complete with pressure-relief and shut-off valves in good working order. Recovery equipment must also be in good working order and suitable for flammable refrigerants. A set of calibrated weighing scales must be available. Hoses must be leak-free and in good condition. Before use, ensure the recovery machine is in satisfactory working order and associated electrical components are sealed to prevent ignition. The recovered refrigerant shall be returned to the supplier in the correct cylinder with a waste transfer note. Do not mix refrigerants in recovery units or cylinders.

Removal Procedure:

1. Unlock the upper and lower vanes using a thin instrument, then remove the horizontal vanes.

2. Remove the 2 screws which fix the panel assembly.

3. Remove the panel assembly. Be sure to remove its bottom right end first.

Installation Procedure:

1. Install the panel assembly by following the removal procedure in reverse.

2. Press the positions indicated by the arrows in the manual to attach the assembly completely to the unit.

3. Install the horizontal vanes.

Refer to the procedures indicated in the installation manual of the outdoor unit for the pump down procedure.

WARNING: When the refrigeration circuit has a leak, do not execute pump down with the compressor. When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes. The compressor may burst if air etc. get into it.

Connect the interface (e.g., Wi-Fi adapter) to the indoor control P.C. board using the connecting cable. Note that cutting or extending the cable will result in connection defects. Keep the connecting cable as far as possible from the power supply cord and other wires.

1. Remove the panel and the lower right corner box.

2. Open the covers of the indoor control P.C. board.

3. Join the connecting cable to connector CN105 on the indoor control P.C. board.

4. Attach the cable clamp provided with the interface to the thick part of the connecting cable with a screw (4×16).

5. Hook the connecting cable into the ribs as shown in the figure in the manual.

6. Close the covers of the indoor control P.C. board, being careful not to catch the thin part of the cable in the cover. Reinstall the panel and the lower right corner box.

WARNING: Fix the connecting cable at the prescribed position securely. Incorrect installation may cause electric shock, fire, and/or malfunction.