R410A Full DC Inverter Split Duct Type Technical Manual MCAC-UTSM-201503
47
P5: Pipe temperature protection
P5: Pipe temperature protection
T3 port on main control board is loose
Fasten the T3 port
T3 sensor is short circuit or disabled
Replace the sensor
Yes
Yes
The indoor load is too large
Make sure the ratio of connectable
IDU is less than 130% or add ODU
No
Yes
No
The heat exchange of condenser
is not good. It may be caused by
dirty heat changer, abnormal ODU
fan running, ODU are too near to
each other, etc.
Check the system and
fixed up the error
No
Yes
The high pressure side of the system is
blocked for squashed pipe, blocked
valve or closed stop valve
Make sure all valves are open,
check the system, and remove
the obstacle
System contains air or nitrogen
Discharge the entire refrigerant. Then
vacuum the system and refill the refrigerant.
Add oil to the system if it leaks.
Yes
No
Yes
No
No
Outdoor main control
board is damaged
Replace the outdoor
main control board