J&E Hall V3 FUSION, Technical Manual

Page: 29 / 36

Issue: 01.06.2023 Page 26
FAULT POSSIBLE CAUSE CHECK SOLUTION
Compressor starting too
frequently
Are controls set correctly - is the
differential on thermostat or LP
switch too small? Check and adjust
Is the liquid line solenoid valve
allowing refrigerant to pass when
closed? Check valve and clean seat or
replace as necessary if damaged
Discharge gas bleeding into
suction side Does suction pressure rise
abnormally when compressor
stops or compressor fails to pump
down correctly? Compressor valve reeds may be
damaged - replace compressor
CONDENSER FAN
Condenser fan will
not run
Power supply
See compressor will not start
section See compressor will not start
section
Compressor contactor not
pulled in See compressor will not start
section See compressor will not start
section
Compressor contactor
pulled in Is voltage being switched across
contactor? If yes - check voltage to FSC and
to fan motor. If correct voltage
present at motor - fan faulty.
Replace fan
If no. Replace faulty contactor
Being controlled by FSC (if
fitted) Is system operating pressure
below FSC setting? If yes - all OK (check fan operates
when pressure rises)
Fan capacitor fault Check visual condition of
capacitor and check capacitance
reading with capacitor meter. Replace capacitor if required
Motor fault If FSC fitted - bypass FSC to test
motor. If motor still does not run -
motor is faulty Replace motor
Condenser fan
runs but only
slowly
Is fan being controlled by
FSC? Is head pressure under control
(~14/15 bar on R448A/449A)
and fan speed increases as head
pressure rises? All OK
Is head pressure above 16 bar
(R448/449A)? Check setting of FSC. Adjust if
necessary.
FSC faulty If fan runs slowly even after
adjusting FSC with head pressure
rising - FSC may be faulty Change FSC
SYSTEM
Insufficient cooling
Lack of refrigerant Is sight glass flashing continuously?
Leak test system and top up with
refrigerant
Condenser coil dirty Visual check of coil condition
Clean condenser coil
Lack of ventilation to unit Any obstructions around unit?
Clear same to ensure good
ventilation
Compressor not pumping
efficiently Carry out pump test on
compressor Replace compressor if fails pump
test
System settings Controls (inc thermostat) set
correctly? Adjust as necessary
T.E.V. Superheat
Adjust as necessary
Service valves do not open
correctly
Are valves fully open?
Adjust as necessary
Restriction in
piping/component Is the filter drier blocked?
Sweating/frosting on outlet of
drier indicates a blockage Replace filter drier
Damage to piping
Replace piping as required
Head pressure too
high
Condenser coil dirty Visual check of coil condition
Clean condenser coil
System overcharged with
refrigerant
Is head pressure high but liquid
line cool to touch?
Reclaim refrigerant/recharge
correctly
Condenser fan not running See above (fan will not run)
See above
FSC (if fitted) not set
correctly Check setting against gauge
pressure Adjust as necessary
Lack of ventilation to unit Any obstructions around unit?
Clear same to ensure good
ventilation
System load too high
(overstocked, door open on
cold-room) Reduce loading