Hitachi RAS-E10H2 Service Manual page 59

6-5. Reversing valve control circuit
In this unit, reversing valve control circuit turns ON/OFF the power to the reversing valve coil by
●
opening/closing the reversing valve relay.
Opening/closing of relay will differ depending on the operation condition. (In the cooling cycle,
●
reversing valve relay is normally ON (close).)
Table 6-3 shows the circuit operation of each operation mode. If the following result is not obtained,
●
reversing valve control circuit may be defective.
Operation mode
Cooling In normal cooling operation
In normal heating operation
Heating
In defrosting operation
Reversing
CN2
valve
3
2
1
Point
Between Pin 29
of microcomputer and 0V
Hi
Lo
Hi
Reversing valve relay
D701
12V
Reversing valve
relay coil
(RL5)
Table 6-3
Between Pin 32 of HIC
and 0V
0V
12V
0V
C−35V
RL5
D−0V
Fig. 6-13
- 63 -
Between 1 and 3 CN2
approx. 35 V
0V (not fixed)
approx. 35 V
Main P.W.B.
HIC
ⅠC2
32 16 1 29