(2) The following situations are not operation failures.
Problem
Mist comes
from the air
conditioner.
Mist comes
from the air
conditioner.
Dust comes
from the air
conditioner.
The air
conditioner
generates
some smell.
DC Inverter U-match Series Cassette Type Unit
Time of occurrence
During operation.
System switches to heating
mode after defrosting.
The air conditioner is buzzing
at the beginning of operation.
When the unit is turned on, it
purrs.
About 20s after the unit first
enables the heating mode or
there is refrigerant brushing
sound when defrosting under
heating.
There is hissing sound when
the unit is started or stopped
and a slight hissing sound
during and after operation.
There is a sound of
crunching during and after
operation.
There is a hissing sound
when the unit is turned on or
suddenly stopped during
operation or after defrosting.
The unit starts operation after
being unused for a long time.
During operation.
Cause
If the unit is running under high
humidity, the wet air in the room
will be quickly cooled down.
Defrosting process will generate
some water, which will turn to
water vapor.
Temperature control will be
buzzing when it starts working.
The noise will become weak
1min later.
When the system is just started,
the refrigerant is not stable.
About 30s later, the purr of the
unit becomes low.
It's the sound of 4-way valve
switching direction. The sound
will disappear after the valve
changes its direction.
It's the sound of gaseous
refrigerant that stops flowing
and the sound of drainage
system.
Because of temperature
change, front panel and other
components may be swelled up
and cause abrasion sound.
Because refrigerant suddenly
stops flowing or changes the
flow direction.
Dust inside the indoor unit
comes out together with the air.
The room smell or the smell of
cigarette comes out through the
indoor unit.
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