Friedrich FSHW091, Service And Parts Manual

Page: 135 / 171

135 PB
TROUBLESHOOTING
36k IPM Protection, Out-of-Step Fault, Compressor Phase Overcurrent
If the connection between control panel AP1 and compressor COMP is secure? If loose? If the connection is in correct order?
If the voltage input of the machine is within normal range? (Use AC voltmeter to measure the voltage between terminal L and N on the wiring board
XT)
If the compressor coil resistance is normal? If the insulation of compressor coil against the copper tube is in good condition?If the
working load of the machine are too high? If the radiation is good?
If the charge volume of refrigerant is correct?
(AP1 below refers to the outdoor control panel)
Energize and
switch on
IPM protection
occurs after the
machine has run for
Please confirm:
a period of time?
1. If the indoor and outdoor heat exchangers are dirty? If they are obstructed by other objects which affect the
heat exchange of indoor and outdoor unit.
2. If the indoor and outdoor fans are working normally?
3. If the environment temperature is too high, resulting in that the system pressure is too high and exceeds the
permissible range?
4. If the charge volume of refrigerant is too much, resulting in that the system pressure is too high?
5. Other conditions resulting in that the system pressure becomes too high.
then energize and start
the unit.
If there is any
abnormality
Take corrective actions
according to Technical
Service Manual, and
described above?
Replace the
If the connection
control panel AP1
between AP1 and
COMP is unsecure
or the connection
order is wrong?
Connect the control panel
AP1 and compressor
COMP correctly according
to the Electrical Wiring
Diagram. Then, energize
and start the unit.
Service Manual.
compressor resistance on
If the
resistance is
normal?
Use ohmmeter to
measure the resistance
between the three
terminals on compressor
COMP, and compare the
measurements with the
Use ohmmeter to
measure the resistance
between the two
terminals of compressor
COMP and copper tube.
Replace the
compressor
COMP
Resistance higher
than 500 MΩ ?
Replace the
AP1
control panel
END
If the unit can
worknormally?
Y
Y
N
N
If the unit can
normally?
work
Y
Y
Y
N
Y
N
Refer to the
Electrical Wiring
Diagram and check
if the connection
between AP1 and
COMP is loose and if
the connection order
is correct.