Rb Unit Abnormal (No Cooling, No Heating, Abnormal Noise); Pipe Temperature In Cooling Mode; Color Of Connector - Fujitsu Airstage VR-II Series Service Manual

SERVICE INFORMATION

RB Unit Abnormal (No Cooling, No Heating, Abnormal Noise)

- Check functioning of Solenoid Valve
- Check Solenoid coil position / connection
- Chedk pipe temperautre difference during operation
Solenoid valve Controlling
SV No.
( Indication on Service Tool )
SV1 ( SVD1 )
SV4 - 6 ( SVS )
SV2 ( SVB2 )
SV3 ( SVB1 )
Position of Solenoid coil
UTP-RX01AH
SV4
SV3 SV2
CAUTION: The solenoid coil which has a heat sink is hot.
When you approach the solenoid coil, turn off the power supply for the RB unit and wait until the temperature of coil becomes low.

Pipe temperature in Cooling mode

Normal Operation
Low Pressure Pipe
Pipe Temp.
COLD
CP3
ST
CV
High Pressure Pipe
CP1
Low Pressure Pipe
Pipe temperature in Heating mode
Normal Operation
High Pressure Pipe Indoor unit Gas Pipe
Pipe Temp.
HOT
ST
High Pressure Pipe
Low Pressure Pipe
* Valve or Pipe Blockage , Opposite operation of Valves can be the cause of Noise problem.
Function
Discharge Valve
Suction Valve
Equalization Valve (Pressurization)
Equalization Valve (Decompression)
UTP-RX01BH / UTP-RX04BH
SV1 SV4
SV5
SV3
Indoor unit Gas Pipe
COLD
Close
SV1
Indoor unit Gas Pipe
Close
ST
SV2
CP2
Open
Open
SV3
SV4
Open
SV5
Open
SV6
HOT
CP3
Open
CV
SV1
Indoor unit Gas Pipe
Open
CP1
SV2
CP2
Close
Close
SV3
SV4
Close
SV5
Close
SV6
Cooling / Dry mode
Close
Open
Close
Open
UTP-RX01BH
SV4
SV1
SV6
SV3
SV2
Possible Cause
Pipe Temp.
High Pressure Pipe
Low Pressure Pipe
When SV4, SV5 SV6 internal blockage or Close position, the refrigerant flow will be lessened,
Indoor unit Gas pipe Temp. > Low pressure pipe temp
Possible Cause
Pipe Temp.
When SV1, blockage or Close position, the refrigerant flow will be lessened,
Indoor unit Gas pipe Temp. < Hi pressure pipe temp
ST
High Pressure Pipe
Low Pressure Pipe
04-90
Fan mode / Stop
Heating mode
Open
Close
Open
Close

Color of Connector

SV1 Green
SV5 SV1
SV2 Blue
SV3 Black
SV4 White
SV5 Red
SV6 Yellow
Solenoid Coil resistance
<Refer to the Parts information 26>
SV2
Low Pressure Pipe Indoor unit Gas Pipe
COLD Less COLD
CP3
Close
ST SV1
CV
Close
CP1
SV2
CP2
Open
SV3
SV4
Indoor unit Gas Pipe
High Pressure Pipe
HOT Less HOT
CP3
ST SV1
CV
Close
CP1
SV2
CP2
Close
Close
SV3 SV4
Close
SV5
Close
SV6
Close
Close
Close
Open
Indoor unit Gas Pipe
ST
SV5
SV6
Indoor unit Gas Pipe
ST