Toshiba A90-0132, Service Manual

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108
14
Troubleshooting
Diagnostic procedure for check code
Check code Operation cause
[d7]
1. Balancing pipe valve (all outdoor units in the
Low oil level detection
connecting line) closed
2. Compressor case oil removal valve closed
3. Miswiring of TK1 sensor/TK2 sensor
4. Refrigerant stagnation in compressor case
5. SV3A, SV3B, SV3C valves error
6. Blockage in oil return circuit of oil separator
7. Blockage in oil tank circuit
Are TK1 and TK2 sensors
correctly connected ?
Check refrigerant stagnation in
compressor case, reset the power
source, and then start the operation.
Replace defective part.
No
Yes
Are balancing pipe valves of all
outdoor units fully open ?
Check connector
Pd sensor: CN516
Ps sensor: CN515
No
Yes
Yes
Is there refrigerant stagnation
in compressor case ?
No
(*1) Is there a 2-way valve
leakage (SV3A, SV3C) or
blockage (SV3B) ?
Replace oil tank circuit.
No leakage/blockage
Yes
Open balancing pipe valve fully, reset
power supply, and start the operation.
[
]
Is the compressor case oil
removal valve fully open ? No
Yes
Open compressor case oil removal
valve fully, reset power supply, and start
the operation.
Replace defective part.
(*2) Is there a blockage in the
oil return circuit of oil separator
(Capillary, strainer) ?
No blockage
Yes
Replace defective part.
Is there blockage in 2-way
valve of all outdoor units in
the connecting line
(SV3A, SV3C) ?
No blockage
Yes
Refrigerant
stagnation is
detected.