Troubleshooting - Mitsubishi Electric M Série Manuel D'installation

6. Troubleshooting

Having trouble?
Air conditioner does not heat or cool well.
When heating operation starts, warm air does not blow from the
indoor unit soon.
During Heat mode, the air conditioner stops before the set room
temperature is reached.
Airflow direction changes during operation or airflow direction
cannot be set.
When the airflow direction is changed, the vanes always move up
and down past the set position before finally stopping at the posi-
tion.
A flowing water sound or occasional hissing sound is heard.
A cracking or creaking sound is heard.
The room has an unpleasant odor.
A white mist or vapor is emitted from the indoor unit.
Water or vapor is emitted from the outdoor unit.
" " appears in the remote controller display.
When restarting the air conditioner soon after stopping it, it does
not operate even though the ON/OFF button is pressed.
Air conditioner operates without the ON/OFF button being press-
ed.
Air conditioner stops without the ON/OFF button being pressed.
SVZ-KP12,18, 24, 30, 36NA
Here is the solution. (Unit is operating normally.)
• Clean the filter. (Airflow is reduced when the filter is dirty or clogged.)
• Check the temperature adjustment and adjust the set temperature.
• Make sure that there is plenty of space around the outdoor unit. Is the indoor unit air intake or
outlet blocked?
• Has a door or window been left open?
• Warm air does not blow until the indoor unit has sufficiently warmed up.
• When the outdoor temperature is low and the humidity is high, frost may form on the outdoor unit.
If this occurs, the outdoor unit performs a defrosting operation. Normal operation should begin
after approximately 10 minutes.
• During Heat mode, the vanes automatically move to the horizontal airflow direction when the air-
flow temperature is low or during defrosting mode.
• When the airflow direction is changed, the vanes move to the set position after detecting the base
position.
• These sounds can be heard when refrigerant is flowing in the air conditioner or when the refriger-
ant flow is changing.
• These sounds can be heard when parts rub against each due to expansion and contraction from
temperature changes.
• The indoor unit draws in air that contains gases produced from the walls, carpeting, and furniture
as well as odors trapped in clothing, and then blows this air back into the room.
• If the indoor temperature and the humidity are high, this condition may occur when operation
starts.
• During defrosting mode, cool airflow may blow down and appear like a mist.
• During Cool mode, water may form and drip from the cool pipes and joints.
• During Heat mode, water may form and drip from the heat exchanger.
• During defrosting mode, water on the heat exchanger evaporates and water vapor may be emit-
ted.
• During central control,
" " appears in the remote controller display.
and air conditioner operation cannot be started or stopped using the remote controller.
• Wait approximately three minutes. (Operation has stopped to protect the air conditioner.)
• Is the on timer set?
Press the ON/OFF button to stop operation.
• Is the air conditioner connected to a central remote controller?
Consult the concerned people who control the air conditioner.
Does " " appear in the remote controller display?
•
Consult the concerned people who control the air conditioner.
• Has the auto recovery feature from power failures been set?
Press the ON/OFF button to stop operation.
• Is the off timer set?
Press the ON/OFF button to restart operation.
• Is the air conditioner connected to a central remote controller?
Consult the concerned people who control the air conditioner.
Does " " appear in the remote controller display?
•
Consult the concerned people who control the air conditioner.
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