Troubleshooting - Mitsubishi Electric PCA-A KA7 Series Operation Manual

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 heating mode, the air conditioner stops before the set room
temperature is reached.
Airflow up/down direction changes during operation or airflow up/down
direction cannot be set.
When the airflow up/down direction is changed, the vanes always move
up and down past the set position before finally stopping at the position.
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 wired remote controller display. (*1)
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 pressed. (*1)
Air conditioner stops without the ON/OFF button being pressed. (*1)
Wired remote controller timer operation cannot be set. (*1)
"PLEASE WAIT" appears in the wired remote controller display. (*1)
An error code appears in the remote controller display.
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 cooling mode, the vanes automatically move to the horizontal
(down) position after 1 hour when the down (horizontal) airflow up/
down direction is selected. This is to prevent water from forming and
dripping from the vanes.
During heating mode, the vanes automatically move to the horizontal
airflow up/down direction when the airflow temperature is low or
during defrosting mode.
When the airflow up/down 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 refrigerant 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 cooling mode, water may form and drip from the cool pipes
and joints.
During heating mode, water may form and drip from the heat
exchanger.
During defrosting mode, water on the heat exchanger evaporates and
water vapor may be emitted.
During central control, " " appears in the wired remote controller
display and air conditioner operation cannot be started or stopped
using the wired remote controller.
Wait approximately 3 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 wired remote controller?
Consult the concerned people who control the air conditioner.
Does " " appear in the wired 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 wired remote controller?
Consult the concerned people who control the air conditioner.
Does " " appear in the wired remote controller display?
Consult the concerned people who control the air conditioner.
Are timer settings invalid?
If the timer can be set, or
controller display.
The initial settings are being performed. Wait approximately 3
minutes.
The protection devices have operated to protect the air conditioner.
Do not attempt to repair this equipment by yourself.
Turn off the power switch immediately and consult your dealer. Be
sure to provide the dealer with the model name and information that
appeared in the remote controller display.
appears in the wired remote
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