V4+R VRF 50/60Hz
201608 75
Part 5 - Diagnosis and Troubleshooting
4.14 P0, P4, H6 Troubleshooting
Digital display output 4.14.1
Description 4.14.2
P0 indicates compressor temperature protection.
P4 indicates discharge temperature protection. When the discharge temperature rises above 115°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..
Possible causes 4.14.3
Outdoor unit stop valves are closed.
Temperature sensor/switch not connected
properly or has malfunctioned.
Insufficient refrigerant.
System blockage.
Indoor load too large.
System contains air or nitrogen.
Poor condenser heat exchange.
Main PCB damaged.
Procedure 4.14.4
ODU stop valves are closed
Compressor top temperature sensor,
discharge pipe temperature sensor
and/or discharge temperature switch
connections on main PCB are loose
1
Ensure the sensors and switch(es) are
connected properly
Compressor top temperature sensor
and/or discharge pipe temperature
sensor have short circuited or failed
2
Replace the faulty sensor(s)
Flowchart continued on next page …