Hitachi RAS-4-HNC - Checking Procedure for the Electronic Expansion Valve for Indoor and Outdoor Units; Checking Procedure for AC Fan Motor

8. Troubleshooting
285
SMGB0079 rev.0 - 01/2013
8
8.4.4 Checking procedure for the electronic expansion valve for indoor and outdoor units
Indoor unit electronic expansion valve Outdoor unit electronic expansion valve
Locked with fully closed Check the liquid pipe temperature during the hea-
ting process. It is abnormal if the temperature
does not increase.
It is abnormal if the liquid pipe pressure
does not increase during the pump down
process.
Locked with slightly open It is abnormal under the following condition:
The temperature of the freeze protection thermis-
tor becomes lower than the suction air tempera-
ture when the unit which is under chechink stops
and the other units are under the pump down pro-
cess.
Electronic expansion valve
Freeze protection thermistor
It is abnormal if the liquid pipe pressure
does not increase and the outlet tempe-
rature of the expansion valve decreases
after the pump down process starts.
Locked with fully open It is abnormal under the following condi-
tions: after the heating process for more
than 30 minutes, the discharge gas tem-
perature of the compressor is not 10°C
higher than the condensing temperature
and there is no other faults, such as an ex-
cessive charge of refrigerant and others.
8.4.5 Checking procedure for AC fan motor
Part name Unit models
Fan motor rated
capacity
Wiring diagram Lead wire colour Resistance (Ω) (at 20ºC)
Fan motor RAS-12HN(P/C)
KFC6S-201SA3P
200W
Main coil 2
Main
coil 1
Auxiliary coil
Thermo
Blue
Orange
Red
White
Black
Black-White
Black-Blue
Black-Red
17.0+-10%
25.3+-10%
20.1+-10%