temperature> of the indoor unit by the out-
door multi controller board operation moni-
tor. During fan operation, linear expansion
valve is closed completely and if there are
Thermistor
some leaking, detecting temperature of
(Liquid pipe)
the thermistor will go lower. If the detected
Linear
expansion
temperature is much lower than the tem-
valve
perature indicated in the remote controller,
it means the valve is not closed all the
way. It is not necessary to exchange the linear expansion
valve, if the leakage is small and not making any trouble.
Check the color of lead wire and missing terminal of the con-
nector.
Closing a valve : 1 → 2 → 3 → 4 → 1
Opening a valve : 4 → 3 → 2 → 1 → 4
The output pulse shifts in above order.
* 1. When linear expansion valve operation stops, all output phase
become OFF.
2. At phase interruption or when phase does not shift in order,
motor does not rotate smoothly and motor will lock and vibrates.
* When the switch is turned on, 2200 pulse closing valve signal will
be send till it goes to
position.
When the valve moves smoothly, there is no noise or vibration
occurring from the linear expansion valve. However, when the
pulse number moves from
more noise can be heard than normal situation.
* Noise can be detected by placing the ear against the screw driver
handle while putting the screw driver to the linear expansion valve.
Check points
6
5
4
3
2
1
LED
34
point in order to define the valve
A
to
or when the valve is locked,
E
A
Countermeasures
Exchange the indoor con-
troller board at drive circuit
failure.
Exchange the linear expan-
sion vale.
Exchange the linear expan-
sion valve.
If large amount of thermis-
tor is leaked, exchange the
linear expansion valve.
Disconnect the connector
at the controller board,
then check the continuity.