MITSUBISHI ELECTRIC MSZ-EX18NLS (01) PDF DOCUMENT

The following tools are required for the installation of the MITSUBISHI ELECTRIC MSZ-EX18NLS:

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 MITSUBISHI ELECTRIC MSZ-EX18NLS unit uses a flammable refrigerant. If refrigerant leaks and comes in contact with fire or a heating part, it will create harmful gas and there is a risk of fire.
Reading Symbol	Read the OPERATING INSTRUCTIONS carefully before operation.
Service Symbol	Service personnel are required to carefully read the OPERATING INSTRUCTIONS and INSTALLATION MANUAL before operation.
Information Symbol (i)	Further information is available in the OPERATING INSTRUCTIONS, INSTALLATION MANUAL, and the like.

The following warnings must always be observed for safety when installing the MITSUBISHI ELECTRIC MSZ-EX18NLS:

WARNING (Could lead to death or serious injury.)

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

• Follow the instructions detailed in the installation manual. Incomplete installation could cause fire or electric shock, injury due to the unit falling, or leakage of water.

• When installing the unit, use appropriate protective equipment and tools for safety. Failure to do so could cause injury.

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

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

• Perform electrical work according to the installation manual and be sure to use an exclusive circuit. Do not connect other electrical appliances to the circuit. An insufficient power circuit capacity or incomplete electrical work could result in a fire or an electric shock.

• Ground the unit correctly. Do not connect the ground wire to a gas pipe, water pipe, lightning rod, or telephone ground. Defective grounding could cause electric shock.

• Do not damage the wires. Damaged wires could cause fire.

• Be sure to shut off the main power when setting up the indoor P.C. board or wiring. Failure to do so could cause electric shock.

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

• Do not install the unit in a place where flammable gas may leak. If gas leaks and accumulates around the unit, it could cause an explosion.

• Do not use an intermediate connection of the power cord or an extension cord. Do not connect many devices to one AC outlet. It could cause a fire or an electric shock.

• Use the parts provided or specified parts for the installation work. Defective parts could cause injury or leakage of water due to a fire, electric shock, the unit falling, etc.

• When plugging the power supply plug into the outlet, make sure that there is no dust, blockage, or loose parts both in the outlet and on the plug. Verify that the power supply plug is completely in the outlet. If there is dust, blockage, or loose parts, it could cause electric shock or fire. If loose parts are found on the power supply plug, replace it.

• Securely attach the electrical cover to the indoor unit and the service panel to the outdoor unit. If not attached securely, dust, water, etc., could collect in the unit and cause a fire or an electric shock.

• When installing, relocating, or servicing the unit, make sure that no substance other than the specified refrigerant (R454B) enters the refrigerant circuit. Any presence of a foreign substance such as air can cause abnormal pressure rise and may result in explosion or injury.

• Do not discharge the refrigerant into the atmosphere. Check that the refrigerant gas does not leak after installation has been completed. If refrigerant leaks during installation, ventilate the room. If refrigerant comes in contact with a fire, harmful gas could be generated.

• Use appropriate tools and piping materials for installation. The pressure of R454B is 1.6 times higher than R22. Not using the appropriate tools and materials, or improper installation could cause the pipes to burst, causing an injury.

• When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes. If disconnected while the compressor is running and the stop valve is open, air could be drawn in, causing the pipes to burst.

• When installing the unit, securely connect the refrigerant pipes before starting the compressor. If the compressor is started before the pipes are connected and the stop valve is open, air could be drawn in, causing the pipes to burst.

• Fasten a flare nut with a torque wrench as specified in this manual. If fastened too tight, a flare nut could break and cause refrigerant leakage.

• Install the unit according to national wiring regulations.

• When using a gas burner or other flame-producing equipment, completely remove all of the refrigerant from the air conditioner and ensure that the area is well-ventilated. If the refrigerant leaks and comes in contact in fire or heating part, it will create harmful gas and there is risk of fire.

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

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

• Do not pierce or burn.

• Be aware that refrigerants may not contain an odour.

• 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.

CAUTION (Could lead to serious injury when operated incorrectly.)

• Depending on the installation area, install a Ground Fault Interrupt (GFI) circuit breaker. If the GFI circuit breaker is not installed, an electric shock could occur.

• Perform the drainage/piping work securely according to the installation manual. If there is a defect in the work, water could drip from the unit and damage household items.

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

• Please wear protective equipment when you touch the base of the outdoor unit. It could cause injury if you do not wear protective equipment.

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

When selecting a location for the indoor unit of your MITSUBISHI ELECTRIC MSZ-EX18NLS, follow these guidelines:

WARNING: The mounting height of the indoor unit shall be 5.9 feet (1.8 m) or more from the floor. Up to 7.5 feet (2.3 m) is recommended. The unit must be installed in a room that exceeds the minimum room area (Amin) determined by the total refrigerant amount (M) as shown in the table below.

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 that meets the following criteria:

• 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. Do not expose to direct sunlight also during the period following unpacking to before use.

• Where it can be easily drained.

• At a distance of 3 feet (1 m) or more away from a TV and radio. Operation of the air conditioner may interfere with radio or TV reception.

• 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 the other heat or steam source.

Avoid the following places for installation:

• Where flammable gas could leak.

• Where there is an excessive amount of machine oil in the air.

• Salty places such as the seaside.

• Where sulfide gas is generated such as a hot spring, sewage, or waste water.

• Where there is high-frequency or wireless equipment.

• Where there is emission of high levels of VOCs, including phthalate compounds, formaldehyde, etc., which may cause chemical cracking.

Select a location for the remote controller for your MITSUBISHI ELECTRIC MSZ-EX18NLS that is:

• Convenient to operate and easily visible.

• Where children cannot easily touch it.

• About 4 feet (1.2 m) above the floor. Check that signals from the remote controller are received by the indoor unit (‘beep’ or ‘beep beep’ sound). If a holder is supplied, install it where 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.

The specifications for the MITSUBISHI ELECTRIC MSZ-EX18NLS are as follows:

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

CAUTION: Be sure to use the insulation of specified thickness. Excessive insulation may cause incorrect installation of the indoor unit, and too little insulation may cause condensate to form.

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)

Check for the following parts before installing your MITSUBISHI ELECTRIC MSZ-EX18NLS.

Included Accessories with Indoor unit

(1) Installation plate	1
(2) Attachment screws for the installation plate (4 x 25 mm)	5
(3) Wireless remote controller	1
(4) Felt tape (For left or left-rear piping)	1
(5) Remote controller holder	1
(6) Screws for the remote controller holder (3.5 x 16 mm, Black)	2
(7) Battery (AAA) for (3)	2
(8) Air cleaning filter	2
(9) Soft dry cloth (NAB type only)	1

Field-Supplied Parts (must be provided on-site)

(A) Indoor/outdoor unit connecting wire	1
(B) Extension pipe	1
(C) Wall hole sleeve	1
(D) Wall hole cover	1
(E) Pipe attachment strap	2 to 5
(F) Screw for (E) 4 x 20 mm	2 to 5
(G) Piping tape	1
(H) Putty	1
(I) Drain hose (or soft PVC hose, 19/32 inches [15 mm] inner diameter or hard PVC pipe VP16)	2 to 5
(J) Refrigerant oil	1
(K) Power supply cord	1

Follow these steps to install the indoor unit of your MITSUBISHI ELECTRIC MSZ-EX18NLS.

1. Attaching the Installation Plate

• Find a stud in the wall to attach the installation plate (1) horizontally by tightening the fixing screws (2) firmly.

• To prevent the plate from vibrating, install the attachment screws in the holes indicated in the installation diagram. For added support, additional screws may be installed in other holes.

• When the knockout is removed, apply vinyl tape to the knockout edges to prevent damaging the wires.

2. Drilling

1. Determine where the holes will be located on the wall.

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.

3. Insert the wall hole sleeve (C).

3. Connecting Wires for Indoor Unit

1. Remove the panel assembly.

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

3. Remove corner box R and electrical cover.

4. Remove 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. The thread of the installed joint appearing inside should be less than 3/8 inch (10 mm).

6. Process the end of the ground wire. Connect it to the ground terminal of the electrical parts box.

7. Process the end of the indoor/outdoor unit connecting wire (A). Attach it to the terminal block. Be careful not to make mis-wiring. Attach the wire securely so its core cannot be seen and no external force affects the connecting section.

8. Firmly tighten the terminal screws. After tightening, 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 corner box R. Reinstall the electrical cover, corner box, and front panel.

Pipe Forming:

• Place the drain hose below the refrigerant piping.

• Make sure that the drain hose is not crowded or bent.

• Do not pull the hose when applying the tape.

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

For Left or Left-Rear Piping:

1. Place the refrigerant piping and the drain hose together, then firmly apply felt tape (4) from the end. The felt tape overlap width should be 1/3 of the tape width.

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 previously attached at the rear of the unit.

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

6. Insert the drain hose into the wall hole sleeve (C) and attach the upper part of the indoor unit onto the installation plate (1). Shift the indoor unit to the left to make placing the piping in the back of the unit easier.

7. Use two rolled pieces of cardboard from the shipping box as spacers to lift the indoor unit.

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

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

Drain Piping:

• Do not cut the drain hose of the unit.

• If the extension drain hose passes through a room, wrap it with insulation.

• 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.

• Ensure no stress is applied to the connecting portion of the drain hose after installation.

• Do not put 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 attached to the indoor and outdoor units, then put them on the pipe.

4. Firmly hold the copper pipe in the flaring tool according to 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, cut off the section and repeat the procedure.

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 as specified in the torque table. When fastened too tight, the flare nut may break and cause a refrigerant leakage.

• Be sure to wrap insulation around the piping. Direct contact with the bare piping may result in burns or frostbite.

• 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 the tightening torque table as a guideline and tighten using two wrenches.

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

Refrigerant Pipe Airtight Test

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

2. Pressurize to 601 psig (4.15 MPa) and measure the surrounding temperature and refrigerant pressure. Add pressure gradually, not all at once.

3. If the specified pressure holds for about one day and does not decrease, the pipes have passed the test and there are no leaks. Note that 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. Look for the source of the gas leak.

Insulation and Taping

1. Cover piping joints with a pipe cover.

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

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, 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 (A) 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-EX18NLS is equipped with an auto restart function. When the power supply is cut off during operation, such as during a blackout, this function automatically starts operation in the previous setting once the power supply is resumed.

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

When breaking into the refrigerant circuit for repairs or any other purpose, conventional procedures shall be used. However, for flammable refrigerants, it is important that best practice is followed.

Removal and Evacuation Procedure:

• remove refrigerant

• purge the circuit with inert gas

• evacuate

• purge again with inert gas

• open the circuit by cutting or brazing.

The refrigerant charge must be recovered into the correct recovery cylinders. For appliances containing flammable refrigerants like the MITSUBISHI ELECTRIC MSZ-EX18NLS, the system shall be “flushed” with OFN to render the unit safe. This may need to be repeated several times. Compressed air or oxygen must not be used for purging refrigerant systems.

Recovery Procedure:

When removing refrigerant from a system for servicing or decommissioning, it is recommended good practice that all refrigerants are removed safely. Use only appropriate, designated, and labeled refrigerant recovery cylinders. The recovery equipment must be in good working order. Before using the recovery machine, check that it is in satisfactory working order and has been properly maintained.

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. Be sure to press the positions as indicated by the arrows in the manual to attach the assembly completely to the unit.

3. Install the horizontal vanes.

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.

For the detailed pump down procedure, refer to the installation manual of the outdoor unit for your MITSUBISHI ELECTRIC MSZ-EX18NLS.

To connect an interface to the indoor control P.C. board of your MITSUBISHI ELECTRIC MSZ-EX18NLS, follow these steps:

• Connect the interface to the indoor control P.C. board with the connecting cable. Do not cut or extend the connecting cable, as this can result in connection defects.

• Do not bundle the connecting cable with the power supply cord, indoor/outdoor connecting wire, and/or ground wire. Keep as much distance as possible between them.

• The thin part of the connecting cable should be stored where customers cannot touch it.

Connection Steps:

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.

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