Toshiba HFC R407C Service Manual page 59

Diagnostic procedure for check code
Check code
[E6]
Fixed-speed IOL, OL alarm
OCR: Overload Current Relay
Does OCR operate ?
Check the OCR reset button.
(Manual reset)
No
Is OCR circuit normal ?
1. OCR unit
2. OCR wiring
Yes
Are gas pipe, liquid pipe, and
service valve of the outdoor
unit fully open ?
Yes
Is outdoor PMV 1
normal?
1. Connector connection
2. Wiring
3. Coil
4. Valve unit
5. Outdoor PC board
Yes
Is IOL circuit normal ?
1. Connector
2. Wiring
3. Outdoor PC board
Yes
Is wiring normal ?
Yes
Insufficient refrigerant, blockage,
pipe breakage.
Troubleshooting
Operation cause
1. Power supply error.
2. Fixed-speed compressor IOL operation.
3. Service valve closed.
4. Blockage in Multi Controller PMV/outdoor PMV 1.
5. Miswiring of communication between indoor and outdoor units.
Yes
No
Repair OCR circuit.
No
Open service valves fully.
No
Repair outdoor PMV.
No
No
(Check miswiring of the outdoor unit according to miswiring check function.)
(Check there is no blockage or pipe breakage.)
Are the following items
related to power supply
normal?
1. Power supply voltage is
400 V ± 10%
2. Phase missing, short-
circuit of fixed-speed
compressor power supply
circuit system
Yes Repair power supply system.
Is Mg-SW defective?
No
Is constant speed
compressor normal ?
1. Is compressor winding
normal ?
2. Is compressor locked?
Yes
Overload operation,
liquid compression
No
Yes
Replace Mg-SW.
No
Replace fixed-speed
compressor.
Repair IOL circuit.
Set normal wiring.
59