Mitsubishi Electric MFZ-KA25VA Operating Instructions Manual page 9

W
HEN YOU THINK THAT TROUBLE HAS OCCURRED
Even if these items are checked, when the unit does not recover from the
trouble, stop using the air conditioner and consult your dealer.
Symptom
Indoor Unit
The unit cannot be operated. • Is the breaker turned on?
• Is the power supply plug connected?
• Is the ON timer set?
• Is there anything that block the normal opera-
tion of the damper?
The unit cannot be operated • This protects the unit according to instruc-
for about 3 minutes when tions from the microprocessor. Please
restarted. wait.
Mist is discharged from the air • The cool air from the unit rapidly cools mois-
outlet of the indoor unit. ture in the air inside the room, and it turns
into mist.
The swing operation of the • This is for the swing operation of the HORI-
HORIZONTAL VANE is ZONTAL VANE to be performed normally.
suspended for a while, then
restarted.
The air fl ow direction changes • In the heating operation, if the air fl ow tem-
during operation. perature is too low or when defrosting is be-
The direction of the horizontal ing done, the horizontal vane is automatically
vane cannot be adjusted with set to vertical position.
the remote controller. • When the air conditioner is operated in
COOL or DRY mode, if the operation con-
tinues with air blowing down for 1 hour, the
direction of the air fl ow is automatically set
to position (1) to prevent condensed water
from dropping.
• The horizontal vane automatically moves
in certain intervals to determine its position,
and then it returns to the set position.
The operation is stopped for • Defrosting of the outdoor unit is being done.
about 10 minutes in the heat- Since this is completed in max.10 minutes,
ing operation. please wait. (When the outside temperature
is too low and humidity is too high, frost is
formed.)
The unit starts operation by • These models are equipped with an auto re-
itself when the main power start function. When the main power is turned
is turned on, though it isn't off without stopping the unit with the remote
operated with the remote controller and is turned on again, the unit
controller. starts operation automatically in the same
mode as the one set with the remote control-
ler just before the shutoff of the main power.
Refer to "Auto restart function" page 4 .
The damper opens and • The damper is automatically controlled by
closes automatically. a microcomputer according to the air fl ow
temperature and operation time of the air
conditioner.
Multi system
The indoor unit which is not • A small amount of refrigerant continues to
operating becomes warm and fl ow into the indoor unit even though it is not
a sound, similar to water fl ow- operating.
ing, is heard from the unit.
When heating operation is • When operation is started during defrosting
selected, operation does not of outdoor unit is done, it takes a few minutes
start right away. (max. 10 minutes) to blow out warm air.
Outdoor Unit
The fan of the outdoor unit • When the outside temperature is low dur-
does not rotate even though ing cooling operation, the fan operates
the compressor is running. intermittently to maintain suffi cient cooling
Even if the fan starts to rotate, capacity.
it stops soon.
Water leaks from the outdoor • During COOL and DRY operations, pipe or
unit. pipe connecting sections are cooled and this
causes water to condense.
• In the heating operation, water condensed
on the heat exchanger drips down.
• In the heating operation, the defrosting op-
eration makes water frozen on the outdoor
unit melt and drip down.
White smoke is discharged • In the heating operation, vapor generated
from the outdoor unit. by the defrosting operation looks like white
smoke.
Explanation & Check points
Page 5
Symptom
Remote controller
The display on the remote • Are the batteries exhausted?
controller does not appear or • Is the polarity (+, -) of the batteries correct?
it is dim. The indoor unit does Page 3
not respond to the remote • Are any buttons on the remote controller of
control signal. other electric appliances being pressed?
Does not cool or heat
The room cannot be cooled or • Is the temperature setting appropriate?
heated suffi ciently. Page 4
• Is the fan setting appropriate? Please change
fan speed to higher setting. Page 5
• Is the air outlet selection switch set to upper
air outlet only? Change to upper and lower air
outlets. Page 5
• Is the fi lter clean?
• Is the fan or heat exchanger of the indoor unit
clean?
• Are there any obstacles blocking the air inlet or
outlet of the indoor or outdoor unit?
• Is a window or door open?
The room cannot be cooled • When a ventilation fan or a gas cooker is used
suffi ciently. in a room, the cooling load increases, resulting
in an insuffi cient cooling effect.
• When the outside temperature is high, the
cooling effect may not be suffi cient.
The room cannot be heated • When the outside temperature is low, the heat-
suffi ciently. ing effect may not be suffi cient.
Air does not blow out soon in • Please wait as the unit is preparing to blow out
the heating operation. warm air.
Airfl ow
The air from the indoor unit • Is the fi lter clean?
smells strange. • Is the fan or heat exchanger of the indoor unit
clean?
• The unit may suck in an odor adhering to the
wall, carpet, furniture, cloth, etc. and blow it out
with the air.
Sound
Cracking sound is heard. • This sound is generated by the expansion/
contraction of the intake grille, etc. due to
change in temperature.
The sound as burbling is • This sound is heard when the outside air is
heard. absorbed from the drain hose by turning on
the range hood or the ventilation fan, mak-
ing water fl owing in the drain hose to spout
out.
This sound is also heard when the outside air
blows into the drain hose in case the outside
wind is strong.
Mechanical sound is heard • This is the switching sound in turning on/off
from the indoor unit. the fan or the compressor.
The sound of water fl owing • This is the sound of refrigerant or condensed
is heard. water fl owing in the unit.
Hissing sound is sometimes • This is the sound when the fl ow of refrigerant
heard. inside the unit is switched.
In the following cases, stop using the air conditioner and consult your
dealer.
• When water leaks or drips from the indoor unit.
• When the upper operation indicator lamp blinks.
• When the breaker trips frequently.
• The remote control signal is not received in a room where an electronic ON/OFF
type fl uorescent lamp (inverter-type fl uorescent lamp, etc.) is used.
• Operation of the air conditioner interferes with radio or TV reception. An ampli-
fi er may be required for the affected device.
• When an abnormal sound is heard.
Explanation & Check points
Page 3
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