Hitachi RAC-25YH4, Service Manual, Page: 88 / 121

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OTHERS
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The indoor fan varies among
high air flow, low air flow and
breeze in the auto fan speed
mode. (Heating operation)
This is because the cool
wind prevention function
is operating, and does
not indicate a fault.
The heat exchanger temperature
is sensed in the auto speed mode.
When the temperature is low, the
fan speed varies among high air
flow, low air flow and breeze.
Loud noise from the outdoor unit is
When the “Sleep” timer is set during
operation,
(1) The indoor fan won’t rotate.
(No air comes from the unit)
(2) The air speed won’t change.
The preset temperature is not
indicated on the remote control.
(1) The temperature arrives at the preset indoor
temperature and the air conditioner unit is
temporarily stopped. Within about 3 minutes,
the fan starts rotation.
(2) When the unit operates at “LOW” air speed,
it continues to operate at the same speed.
When automatic operation is performed, the
preset temperature won’t be indicated.
However, you can adjust the temperature within
a range of
±
3
°
C by pressing the “Room
Temperature” button.
If the temperature is 1
°
C higher than the auto
preset temperature, 1
°
C will appear.
If the temperature is 1
°
C lower than the auto
preset temperature, 1
°
C will appear.
heard when operation is started.
When operation is started, the compressor
rotation speed goes to maximum to increase the
heating or cooling capability, so noise becomes
slightly louder. This does not indicate a fault.
Noise from the outdoor unit
occasionally changes.
The compressor rotation speed changes according to
the difference between the thermostat set temperature
and room temperature. This does not indicate a fault.
There is a difference between the set
temperature and room temperature.
There may be a difference between the set
temperature and room temperature because of
construction of room, air current, etc. Set the
temperature at a comfortable for the space.
Air does not flow immediately
after operation is started.
Preliminary operation is performed for one
minute when the power switch on and heating
or dehumidifying is set. The operation lamp
blinks during this time for heating. This does
not indicate a fault.
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RAS_25_35_AW_055-086 2003.12.31, 10:59 AM 86