BEFORE CONTACTING THE SERVICE REPRESENTATIVE, CHECK THE FOLLOWING AGAIN. Mitsubishi Electric MUH-GA20VB

BEFORE CONTACTING THE SERVICE REPRE-

SENTATIVE, CHECK THE FOLLOWING AGAIN

Question Check points or Remedy

The air conditioner cannot be operated.

• Is the breaker turned on?

• Is the fuse blown?

• Is the ON timer set? (Page 8)

The room cannot be cooled or heated sufficiently.

• Is the temperature setting correct? (Page 7)

• Is the filter clean? (Page 9)

• Are there any obstacles blocking the air inlet or outlet of the indoor or outdoor unit?

• Is a window or door open?

The air from the indoor unit smells strange.

• Is the filter clean? (Page 9)

The display on the remote controller does not appear or it is dim. The indoor unit does not respond to the remote control signal.

• Are the batteries exhausted? (Page 5)

• Is the polarity (+, -) of the batteries correct?

(Page 5)

• Are any buttons on the remote controller of other electric appliances being pressed?

When a power failure occurs.

• Does the air conditioner start operating again?

If the air conditioner had operated before the power failure, as these models are equipped with an auto restart function, the air conditioner should start operating again. (Refer to Description of “AUTO RESTART FUNCTION” on page

6.)

Even if the above items are checked, when the air conditioner does not recover from the trouble, stop using the air conditioner and consult your dealer.

In the following cases, stop using the air conditioner and consult your dealer.

• When water leaks from the indoor unit.

• When the left operation indicator lamp blinks.

• When the breaker trips frequently.

• The remote control signal may not be received in a room where an electronic

ON/OFF type fluorescent lamp (inverter-type fluorescent lamp, etc.) is used.

• Operation of the air conditioner may interfere with radio or TV reception in areas where the reception is weak. An amplifier may be required for the affected device.

• When thunder is heard, stop operation and disconnect the power supply plug or turn off the breaker. Otherwise, the electrical parts may be damaged.

WHEN YOU THINK THAT TROUBLE HAS OCCURRED

Question Answer (not a malfunction)

The air conditioner cannot be operated for about 3 minutes when restarted.

• This protects the air conditioner according to instructions from the microprocessor. Please wait.

Cracking sound is heard.

• This sound is generated by the expansion/contraction of the front panel, etc. due to change in temperature.

The air from the indoor unit smells strange.

• The air conditioner may suck in an odor adhering to the wall, carpet, furniture, cloth, etc. and blow it out with the air.

The fan stops during the

DRY operation.

• In DRY operation, the unit operates using the same refrigerant circuit as in COOL operation.

DRY operation time has to be reduced in order to lower humidity without much room temperature decreasing. So the compressor sometimes stops, and at the same time the indoor fan stops.

This prevents water condensed on the heat exchanger from evaporating again.

The sound of water flowing is heard.

• This is the sound of refrigerant flowing inside the air conditioner.

• This is the sound of condensed water flowing in the heat exchanger.

• This is the sound of the heat exchanger defrosting.

The sound as burbling is heard.

• This sound is heard when the outside air is absorbed from the drain hose in turning on the range hood or the ventilation fan and that makes water flowing in the drain hose sucked up.

This sound is also heard when the outside air blows into the drain hose in case the outside wind is strong.

The room cannot be cooled sufficiently.

• When a ventilation fan or a gas cooker is used in a room, the cooling load increases, resulting in an insufficient cooling effect.

• When the outside air temperature is high, the cooling effect may not be sufficient.

Mist is discharged from the air outlet of the indoor unit.

• The cool air from the air conditioner rapidly cools moisture in the air inside the room, and it turns into mist.

Question Answer (not a malfunction)

The air flow direction changes during operation.

The direction of the horizontal vane cannot be adjusted with the remote controller.

• When the air conditioner is operated in COOL or DRY mode, if the operation continues with air blowing down for 1 hour, the direction of the air flow is automatically set to horizontal to prevent condensed water from dropping.

• In the heating operation, if the air flow temperature is too low or when defrosting is being done, the horizontal vane position is automatically set to horizontal.

Water leaks from the outdoor unit.

• During COOL and DRY operations, pipe or pipe connecting sections are cooled and this causes water to condense.

• In the heating operation, the defrosting operation makes water frozen on the outdoor unit melt and drip down.

• In the heating operation, water condensed on the heat exchanger drips down.

White smoke is discharged from the outdoor unit.

• In the heating operation, vapor generated by the defrosting operation looks like white smoke.

Air does not blow out soon in the heating operation.

• Please wait as the air conditioner is preparing to blow out warm air.

The operation is stopped for about 10 minutes in the heating operation.

• Defrosting of the outdoor unit is being done (Defrosting operation).

Since this is completed in 10 minutes, please wait. (When the external temperature is too low and humidity is too high, frost is formed.)

Hissing sound is sometimes heard.

• This is the sound when the flow of refrigerant inside the air conditioner is switched.

The room cannot be heated sufficiently.

• When the outside air temperature is low, the heating effect may not be sufficient.

In a multi-unit system, the indoor unit which is not operating becomes warm and a sound, similar to water flowing, is heard from the unit.

• A small amount of refrigerant continues to flow into the indoor unit even though it is not operating.

The air conditioner starts the operation only with the main power turned on, though you do not operate the unit with the remote controller.

• These models are equipped with an auto restart function. When the main power is turned off without stopping the air conditioner with the remote controller and is turned on again, the air conditioner will start operation automatically in the same mode as the one set with the remote controller just before the shutoff of the main power.

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