DC Inverter U-match Series Cassette Type Unit
52
(2) The following situations are not operation failures.
Problem
Time of occurrence
Cause
Mist comes from
the air
conditioner.
During operation.
If the unit is running under
high humidity, the wet air in
the room will be quickly
cooled down.
The air
conditioner
generates some
noise.
System switches to heating
mode after defrosting.
Defrosting process will
generate some water, which
will turn to water vapor.
The air conditioner is buzzing
at the beginning of operation.
Some components will be
buzzing when it starts
working. The noise will
become weak 1min later.
When the unit is turned on, it
purrs.
When the system is just
started, the refrigerant is not
stable. About 30s later, the
purr of the unit becomes low.
About 20s after the unit first
enables the heating mode or
there is refrigerant brushing
sound when defrosting under
heating.
It’s the sound of 4-way valve
switching direction. The
sound will disappear after the
valve changes its direction.
There is hissing sound when
the unit is started or stopped
and a slight hissing sound
during and after operation.
It’s the sound of gaseous
refrigerant that stops flowing
and the sound of drainage
system.
There is a sound of crunching
during and after operation.
Because of temperature
change, front panel and other
components may be swelled
up and cause abrasion sound.
The air
conditioner
generates some
noise.
There is a hissing sound when
the unit is turned on or
suddenly stopped during
operation or after defrosting.
Because refrigerant suddenly
stops flowing or changes the
flow direction.
Dust comes
from the air
conditioner.
The unit starts operation after
being unused for a long time.
Dust inside the indoor unit
comes out together with the
air.
The air
conditioner
generates some
smell.
During operation.
The room smell or the smell of
cigarette comes out through
the indoor unit.
