2.23 P4, H6: Discharge temperature protection or discharge temperature switch protection
Digital display output
Description
ï‚§ Discharge temperature protection.
ï‚§ All units stop running.
ï‚§ Error code is displayed on the unit with the error.
Trigger / recover condition
 Discharge temperature protection
ï‚§ Trigger condition:
For P4 protection: Discharge temperature (T7C1) ≥ 115
o
C.
ï‚§ Recover condition: Discharge temperature (T7C1) < 90
o
C.
ï‚§ Reset method:
For P4 protection: Resume automatically.
 Discharge Temp. switch protection
 Trigger condition: Discharge temperature ≥ 115
o
C.
ï‚§ Recover condition: Discharge temperature < 75
o
C.
ï‚§ Reset method: Resume automatically.
 H6 protection
ï‚§ For H6 protection: P4 protection appears three times in 100 minutes.
ï‚§ Reset method:
For P4 protection: Resume automatically.
For H6 protection: Manually restart.
Possible causes
ï‚§ Outdoor unit stop valves are closed.
ï‚§ Temperature sensor/switch not connected
properly or has malfunction.
ï‚§ System contains air or
nitrogen.
ï‚§ Poor condenser heat exchange.
ï‚§ Outdoor main PCB damaged.