Troubleshooting; Common Problems - Pioneer YN-M Series Owner's Manual

Troubleshooting

CAUTIONS
If one of the following conditions occur, switch off the power supply immediately and contact
your installer or dealer for further assistance.
The operation light continues to flash rapidly after the unit has been restarted.
•
The remote control buttons do not work.
•
The unit continually trips fuses or circuit breakers.
•
A foreign object or water enters the air conditioner.
•
Any other abnormal situation.
•

Common Problems

The following symptoms are not a malfunction and in most situations will not require repairs.
Problem
Unit does not
turn on when
pressing ON/
OFF button
The unit changes
from COOL mode
to FAN mode
The indoor unit
emits white mist
Both the indoor
and outdoor units
emit white mist
The indoor unit
makes noises
Both the indoor
unit and outdoor
unit make noises
The outdoor unit
makes noises
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The unit has a 3-minute protection feature that prevents the unit from
overloading. The unit cannot be restarted within three minutes of being
turned off, and within 3 minutes of each initial startup.
Cooling and Heating Models: If the Operation light and PRE-DEF (Pre-heating/
Defrost) indicators are lit up, the outdoor temperature is too cold and the unit' s
warm-start mode is activated in order to defrost the unit.
In Cooling-Only Models: If the "Fan-Only" indicator is lit up, the outdoor
temperature is too cold and the unit' s anti-freeze protection is activated in
order to defrost the unit.
The unit changes its setting to prevent frost from forming onto the unit. Once
the temperature increases, the unit will start operating again.
The set temperature has been reached, at which point the unit turns off the
compressor. The unit will resume operating when the temperature fluctuates
again.
In humid regions, a large temperature difference between the room' s air and
the conditioned air can cause white mist.
When the unit restarts in HEAT mode after defrosting, white mist may be
emitted due to moisture generated from the defrosting process.
A squeaking sound is heard when the system is OFF or in COOL mode. The
noise is also heard when the drain pump (optional) is in operation.
A squeaking sound may occur after running the unit in HEAT mode due to
expansion and contraction of the unit' s plastic parts.
A low hissing sound may occur during operation. This is normal and is caused
by refrigerant gas flowing through both the indoor and outdoor units.
A low hissing sound may be heard when the system starts, has just stopped
running or is defrosting. This noise is normal and is caused by the refrigerant
gas stopping or changing direction.
The unit will make certain expected sounds based on its operating mode.
Possible Causes
4