Carrier 25VNA Service Manual page 24

B
WARNING!
Disconnect &
lock -out power
and recover
system charge
Remove the
molded plug from
the thermistor
fusite on the
compressor
(See Fig. 19)
Measure
resistance
between each of
the three fusite
pins and ground
(See Fig. 20 & 21)
Is there continuity
Change the
between any of the
compressor
pins and ground?
Yes
No
The molded plug
harness is
grounded - replace
it
Install new
molded plug
assembly and
route wires
carefully
A
Reset motor
temp fault at
system controller
WARNING!
Disconnect &
lock-out power,
allow 2 minutes
for drive to
discharge
Check and verify
correct drive part
number
Confirm phasing
is correct to
compressor
(yellow, black,
red wires on
drive output.
(See Fig. 23)
Put system back
into operation
Check system
refrigerant
charge & air flow
Check for
restricted
refrigerant flow
and/or high
superheat
Fig. 15 – Motor Temp Fault Troubleshooting - - Part 2
A
Confirm
operation inside
compressor/unit
temperature &
speed range
Is input current to
drive less than unit
full load amp rating?
System still
faulting on
motor temp?
Normal
operation --
monitor
24
Replace
compressor
No
Yes
Troubleshoot the
thermistor circuit
Yes
No
C
A11555