V5 X VRF 50/60Hz
4.15 P0, P4, H6 Troubleshooting
4.15.1
Digital display output
4.15.2
Description
P0 indicates compressor temperature protection.
P4 indicates discharge temperature protection. When the discharge temperature rises above 120°C the system
displays P4 protection and all units stop running.
H6 indicates P4 protection has occurred 3 times in 100 minutes. When an H6 error occurs, a manual system restart is
required before the system can resume operation.
Error code is only displayed on the unit with the error.
4.15.3
Possible causes
Outdoor unit stop valves are closed.
Temperature sensor/switch not connected
properly or has malfunctioned.
4.15.4
Procedure
ODU stop valves are closed
Compressor top temperature sensor,
discharge pipe temperature sensor
and/or discharge temperature switch
connections on main PCB are loose
Compressor top temperature sensor
and/or discharge pipe temperature
sensor have short circuited or failed
82
P0 / P4 / H6
No
1
No
2
No
Insufficient refrigerant.
System blockage.
Indoor load too large.
Yes
Open the stop valves
Ensure the sensors and switch are
Yes
connected properly
Yes
Replace the faulty sensor(s)
Flowchart continued on next page ...
System contains air or nitrogen.
Poor condenser heat exchange.
Main PCB damaged.
201608