Trane TVR Pro CO Series Service Manual page 102

Procedure
ODU stop valves are closed
Insufficient refrigerant caused by
The low pressure side is blocked, caused
by crushed or bent pipe, blocked EXV, or
The evaporator heat exchange is poor
Replace outdoor main PCB
Notes:
1. An insufficiency of refrigerant causes compressor discharge temperature to be higher than normal, discharge and suction pressures to be lower than
normal and compressor current to be lower than normal, and may cause frosting to occur on the suction pipe. These issues disappear once sufficient
refrigerant has been charged into the system. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 "Normal Operating Parameters of
Refrigerant System".
2. A low pressure side blockage causes compressor discharge temperature to be higher than normal, suction pressure to be lower than normal and
compressor current to be lower than normal, and may cause frosting to occur on the suction pipe. For normal system parameters refer to Table 6-3.4 and
6-3.5 in Part 6, 3.2 "Normal Operating Parameters of Refrigerant System".
3. In cooling mode check indoor heat exchangers, fans and air outlets for dirt/blockages. In heating mode check outdoor heat exchangers, fans and air outlets
for dirt/blockages.
P2 / H5
No
refrigerant leakage
1
No
dirty filter
2
No
No
Yes
Add refrigerant or inspect the system for
Yes
Inspect the system and fix the error. If the
Yes
filter is blocked by ice, the piping should
Yes
Inspect the system and fix the error
5
101
Open the stop valves
leaks
be cleaned