Checking Procedure For The Reversing Valve; Actions Of 4-Way Solenoid Valve; Monostable Solenoid Operation Type - Hitachi RAS-(3-6)HVNC1(E) Service Manual

8 Troubleshooting
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Checking procedure for the reversing valve
Troubleshooting
Is the connector PCN(6/100) *1)
on PCB1 connected correctly?
Yes
Is the resistance of the reversing
valve coil *2) correct?
Yes
Is there output voltage *3)
generated from the connector
PCN(6/100 )*1) on PCB1?
Yes
Reversing valve is faulty (valve lock-
ing, etc.). Replace it with a new one.
Output voltage
Reversing valve ON
Test lead (+side)
Test lead (-side)
Range of voltaje
Actions of 4-way solenoid valve
Monostable solenoid operation type
Operation Mode: Heating Reversing Valve Coil: ON
Electric Current Applied
Current is applied to the reversing valve coil and so attraction is
generated. The plunger position is kept by the electromagnetic
force.
Coil
Attractor
Magnetic
Coil case
screw
Spring force
313
SMGB0087 rev.0 - 12/2013
No
Connect it correctly.
No
Reversing valve is faulty (disconnec-
tion, etc.). Replace it with a new one.
No
PCB1 is faulty (Faulty reversing
valve circuit, etc.). Replace it with a
new one.
Reversing valve OFF
pin 1 pin 3
pin 3 pin 1
325 VDC 163 VDC
Plunger
Plunger position
Electromagnetic force (Posi-
tion keeping force)
Electrical circuit
N O T E
*1) PCB1 connnector PCN100 (PCN6
RAS-(2-2.5)HVNP1,
ANDRAS-(4-6)H(V)NC1E), pin 1 - 3
*2) See in the table "Resistance (Ω)"
*3) See in the table"Output voltage" ac-
cording to coil type operation mode.
N O T E
The values may differ depending on testers.
Appropriate output voltage is 70~339VDC
Operation Mode: Cooling Reversing Valve Coil: OFF
No Electric Current Applied
No current is applied to the reversing valve coil and so no attrac-
tion is generated. The plunger position is kept by spring force.
Coil
Attractor
Magnetic Coil case
screw
Spring force
(Position keeping force)
RAS-3HVNC1
Plunger
Plunger position
Electromagnetic force = 0
8