Carrier 619FB Service Manual page 39

6. Diagnosis for compressor synchronism (AP1 below is control board of the outdoor unit)
Main detection points:
S Is the system pressure high?
S Is the voltage too low?
Malfunction diagnosis process:
Synchronism after
energize the unit
and start it
No
If the stop time of
compressor is more than
3min
Yes
If the compressor wire COMP(UVW) is well
connected, the connection sequence
forwards to clockwise direction?
No
Connect Yes
wire well
Replace
control board
AP1
Remove
Yes
malfunction?
No
Replace
compressor
End
Synchronism
occurred during
operation
If the outdoor fan works
No
normally?
Yes
If the radiating of unit is
Yes
well?
No
If the input voltage of unit
No N
is normal?
Yes
If the refrigerant is too
Yes
much?
No
Replace
control board
AP1
Remove
malfunction?
Yes
No
Replace
compressor
End
Fig. 42 – Troubleshooting
39
Check if the fan
Replace fan
terminal OFAN is
capacitor C1
connected well
Improve the radiating
outdoor fan
of unit (clean heat
exchanger and
increase ventilation)
Start to run until the
power resume normal
voltage
Charge the
refrigerant with
service manual
Replace