MITSUBISHI ELECTRIC MSZ-EX15NLW (01) PDF DOCUMENT

The symbols displayed on your MITSUBISHI ELECTRIC MSZ-EX15NLW indoor and/or outdoor unit have the following meanings:

• WARNING (Risk of fire) A2L: This symbol indicates that the unit uses a flammable refrigerant. If refrigerant leaks and comes into contact with a fire or heating part, it will create harmful gas and there is a risk of fire.
• Book with “i” symbol: This symbol indicates that you should read the OPERATING INSTRUCTIONS carefully before operation.
• Gears symbol: This symbol indicates that service personnel are required to carefully read the OPERATING INSTRUCTIONS and INSTALLATION MANUAL before operation.
• Information “i” symbol: This symbol indicates that further information is available in the OPERATING INSTRUCTIONS, INSTALLATION MANUAL, and the like.

The following warnings and cautions must always be observed for your safety when installing and operating the MITSUBISHI ELECTRIC MSZ-EX15NLW.

WARNINGS (Could lead to death or serious injury):

Do not install the unit by yourself. Improper installation could cause fire, electric shock, or injury. Consult a qualified installer.

Follow the instructions in the installation manual. Incomplete installation could cause fire, electric shock, or injury.

Use appropriate protective equipment and tools for safety during installation.

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

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

Perform electrical work according to the 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. This could cause a fire.

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

Use specified wires to securely connect the indoor and outdoor units. Improper connection could cause a fire.

Do not install the unit where flammable gas may leak.

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

Use the provided or specified parts for installation work.

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

Securely attach the electrical cover to the indoor unit and the service panel to the outdoor unit.

When installing, relocating, or servicing, ensure no substance other than the specified refrigerant (R454B) enters the refrigerant circuit.

Do not discharge refrigerant into the atmosphere. Ventilate the room if refrigerant leaks during installation.

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.

Securely connect the refrigerant pipes before starting the compressor during installation.

Fasten a flare nut with a torque wrench as specified. Overtightening can cause breakage and leakage.

Install the unit according to national wiring regulations.

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.

Do not use means to accelerate defrosting or to clean other than those recommended by the manufacturer.

The appliance shall be stored in a room without continuously operating ignition sources.

Do not pierce or burn the unit.

Pipe-work shall be protected from physical damage and comply with codes and standards.

CAUTIONS (Could lead to serious injury when operated incorrectly):

Depending on the installation area, install a Ground Fault Interrupt (GFI) circuit breaker.

Perform the drainage/piping work securely according to the installation manual.

Do not touch the air inlet or the aluminum fins of the outdoor unit.

Wear protective equipment when you touch the base of the outdoor unit.

Do not install the outdoor unit where small animals may live.

The following tools are required for the installation of the MITSUBISHI ELECTRIC MSZ-EX15NLW:

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

Select a location for the indoor unit that meets the following criteria:

• The mounting height shall be 5.9 feet (1.8 m) or more from the floor. Up to 7.5 feet (2.3 m) is recommended.
• The room must exceed the minimum room area (Amin) determined by the total refrigerant amount (M), as specified in the manual’s table.
• 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) or more away from a TV and radio.
• In a place as far away as possible from fluorescent and incandescent lights.
• Where the air filter can be removed and replaced easily.
• Where it is away from other heat or steam sources.

Note: Install the indoor unit high on the wall where air can distribute over the entire room.

Avoid the following places for installation:

• Where flammable gas could leak.
• Where there is an excessive amount of machine oil in the air.
• Where oil is splashed or the area is filled with oily smoke.
• Salty places such as the seaside.
• Where sulfide gas is generated (e.g., hot springs, sewage).
• Where there is high-frequency or wireless equipment.
• Where there is emission of high levels of VOCs (e.g., phthalate compounds, formaldehyde).

The unit must be installed in a room that exceeds the minimum room area (Amin), which is determined by the total refrigerant amount (M). The requirements for a system without a branch box are as follows:

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

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 Piping Specifications:

Pipe	Outside diameter inch (mm)	Minimum wall thickness inch (mm)	Insulation thickness inch (mm)	Insulation material
For liquid	1/4 (6.35)	0.0315 (0.8)	5/16 (8)	Heat resistant foam plastic 0.045 specific gravity
For gas	3/8 (9.52)	0.0315 (0.8)	5/16 (8)
	1/2 (12.7)	0.0315 (0.8)	5/16 (8)

General Wiring and Piping Notes:

• Power should be from an exclusive branched circuit. Follow applicable technical standards and local electrical codes.
• Use solid or stranded conductor Minches AWG14 for connecting wires and power supply. Use copper conductors only.
• To prevent condensation, insulate both refrigerant pipes. Use insulation of the specified thickness.
• Refrigerant pipe bending radius must be 4 inches (100 mm) or more.

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 into the holes indicated in the illustration to prevent vibration.

3. For added support, additional screws may be installed in other holes.

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

Drilling:

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

2. Drill a 3-inch (75 mm) diameter hole. The outdoor side of the hole should be 6/32 to 9/32 inch (5 to 7 mm) lower than the indoor side.

3. Insert the wall hole sleeve (C).

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 straight joint (for rear piping) or elbow joint (for right, left, or downward piping) to the conduit plate with a lock nut.

6. Process the end of the ground wire 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 no mis-wiring. Attach the wire firmly so its core cannot be seen and no external force affects the connection.

8. Firmly tighten the terminal screws and verify that the wires are tightly 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 R. Reinstall the electrical cover, corner box, and front panel.

Pipe Forming:

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 the drain hose together and 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 originally attached at the rear of the unit.

5. Insert the drain hose fully into the drain pan at the back right of the unit, checking 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 left for easier piping.

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

8. Connect the refrigerant piping with the extension pipe.

9. Attach the lower part of the indoor unit to the installation plate.

Drain Piping:

The drain hose should point downward for easy drainage. If the provided hose is too short, connect it with a field-supplied drain hose. When connecting to a hard vinyl chloride pipe, insert it securely. Ensure no stress is applied to the drain hose connection. Do not apply any agent on the drain port. Do not place the drain pipe directly in a drainage ditch where ammonia or sulphuric gas may be generated.

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. Select the “A” dimension from the table according to your tool.

5. Check the flared work. If it’s defective, cut off the section and repeat.

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 as specified in the table. 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 the joints to the specified torque. For the outdoor unit, connect pipes to the stop valve pipe joint using the same procedure.

Refrigerant Pipe Airtight Test:

1. Connect testing tools. Ensure stop valves are closed.

2. Add pressure to the refrigerant lines through the service port of the GAS stop valve to 601 psig (4.15 MPa). Add pressure gradually.

3. If the pressure holds for about one day and does not decrease, the pipes have passed the test. If the surrounding temperature changes by 1°F (0.5°C), the pressure will change by about 1 psig (0.007 MPa); make necessary corrections.

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

Insulation and Taping:

1. Cover piping joints with a pipe cover.

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

3. Apply piping tape (G) starting from the connection on the outdoor unit. Use additional field-supplied insulation if piping is installed through a ceiling, closet, or where temperature and humidity are high 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 be performed 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.

Yes, the MITSUBISHI ELECTRIC MSZ-EX15NLW 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.

Caution: After a test run, turn off the unit with the E.O. SW or remote controller before turning off the power supply. If not, the unit will automatically begin operation when the power supply is resumed.

When breaking into the refrigerant circuit for repairs or other purposes, it is important that best practice is followed since flammability is a consideration. Adhere to the following 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. For appliances containing flammable refrigerants, the system shall be “flushed” with OFN to render the unit safe. This may need to be repeated several times. Do not use compressed air or oxygen for purging refrigerant systems.

When removing refrigerant from a system for servicing or decommissioning, it is recommended good practice that all refrigerants are removed safely. Use only appropriate refrigerant recovery cylinders and ensure they are correctly labeled. The recovery equipment must be in good working order.

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 following the removal procedure in reverse.

2. Be sure to press the positions indicated by the arrows to attach the assembly completely to the unit.

3. Install the horizontal vanes.

To remove the indoor unit, first remove the bottom of the unit from the installation plate. When releasing the corner part, release both the left and right bottom corner parts of the indoor unit and pull it downward and forward as shown in the figure in the manual.

Connect the interface to the indoor control P.C. board of the air conditioner with the connecting cable. Note that cutting or extending the cable can result in connection defects. Keep the connecting cable as far as possible from the power supply cord, indoor/outdoor connecting wire, and ground wire. The thin part of the cable should be stored where customers cannot touch it.

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 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 as shown in the figure.

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

6. Close the covers of the indoor control P.C. board. Be careful not to catch the thin part of the connecting 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.