Appendix - J&M CellarPlus 70-S1/S3 Technical Manual

Appendix

Table 13: Trouble Shooting
FAULT POSSIBLE CAUSE
COMPRESSOR
Compressor will Power supply
not start
Compressor contactor not
pulled in (contactor in
outdoor unit)
Compressor contactor
pulled in but compressor
not running
LP switch tripped (on
outdoor unit)
Compressor internal
overload tripped
Faulty compressor run
capacitor
Motor windings faulty
Compressor seized
Compressor runs Mechanical failure within
but no effect on compressor
suction/discharg
e pressures
Compressor Operating on safety
starts and stops controls
too quickly
Refrigerant levels
Faulty contactor (if fitted)
Anti short cycle time in
controller is set too low
Temperature differential
in controller set too low
Room temperature rising
too quickly
Issue: 01.06.2023
CHECK
Is power switched on?
Phase and neutral present?
Voltage within tolerance?
Is there correct voltage to
contactor coil? (Terminals
A1 & A2)
Is the controller calling for
cooling? (Cooling LED lit)
Is the controller on defrost?
(Defrost LED lit
Is there an alarm condition
shown on the controller
display?
Has a safety switch tripped
out?
Is voltage being switched
across contactor? (Terminals L
& T)
Low pressure condition
Is the correct voltage at
compressor terminals?
Check visual condition of
capacitor and check uF reading
with capacitor meter.
Check resistances of windings
Does compressor attempt to
start but does not run correctly
(makes humming sound)? Are
amps equivalent to LRC rating?
Are compressor motor amps
lower than expected? If so -
potentially valve damage or
other internal wear/damage
Check LP switch and
compressor internal overload
Is there too little refrigerant in
the system causing LP switch
tripping?
Are the contacts chattering on
the contactor?
Anti short cycle time should be
set for minimum of 3 minutes
Differential should be set for
minimum of 2°C
Are doors open to room?
SOLUTION
If not - switch on
Check/rectify
Check/rectify
If yes - coil faulty. Replace contactor
If yes - check for break in control circuit
If yes - wait for defrost to finish or
terminate defrost and check operation
Refer to manual for alarm identification
and resolution
Check cause and rectify
If yes - check voltage present at
compressor terminals. If correct -
compressor may have tripped internal
overload or be faulty
If no. Replace faulty contactor
Low refrigerant charge/icing of
evaporator coil/evaporator fan
failure/blockage in piping. Check &
rectify cause
Compressor has overheated - allow
time for reset (up to 3 hours) and
rectify cause
Replace capacitor as required
Windings that show open circuit could
be due to internal overload trip. Wait
for reset and recheck. If continually
open circuit - motor faulty. Replace
compressor.
If all electrical checks on components as
above are OK - Change compressor
Try pump test on compressor. If test
fails - replace compressor.
Rectify cause and recheck
Check refrigerant level and adjust
accordingly
Contacts may be dirty or worn. Check
and replace contactor as necessary
Check and rectify
Check and rectify
Check and rectify
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