Hydro Unit
Check
code
Operational cause
Compressor lock
H02
Defect in the current detection
H03
circuit
Operation of case thermostat
H04
Unset service PC board jumper
L10
Jumpers have not been cut.
The communication between the
L29
outdoor PC board MUCs error
The outlet temperature error
P03
P04
The high pressure switch error
P05
The power supply voltage error
Overheating of heat-sink error
P07
Detection of gas leak
P15
43-EN
Diagnostic functional operation
Backup
present
Automatic
reset
1. Defect of compressor (lock)
×
– Replace the compressor.
O
2. Defect of compressor wiring (open phase).
×
O
1. Replace the outdoor inverter control board.
1. Check the refrigeration cycle (gas leak).
2. Check the case thermostat and connector.
×
O
3. Check that the service valve is fully open.
4. Defect of the pulse motor valve.
5. Check for kinked piping.
×
O
1. Cut outdoor PC board jumper wire (for service).
×
O
1. Replace the outdoor control board.
1. Check the refrigeration cycle (gas leak).
2. Defect of the pulse motor valve.
×
O
3. Check the resistance value of the discharge
temperature sensor (TD).
×
O
×
O
1. Check the power supply voltage.
1. Check the thread fastening and heat-sink grease
between the outdoor control board and the heat-sink.
×
O
2. Check the heat-sink fan duct.
3. Check the resistance value of the heat-sink
temperature sensor (TH).
1. Check the refrigeration cycle (gas leak).
2. Check that the service valve is fully open.
3. Defect of the pulse motor valve.
×
O
4. Check for kinked piping.
5. Check the resistance value of the discharge
temperature sensor (TD) and the suction temperature
sensor (TS).
– 44 –
Installation Manual
Determination and action