Parker Hiross Polestar-Smart PST1200, User Manual, Page: 14 / 178

English
6/6
PST 460-1800
7 Troubleshooting
FAULT CAUSE
REMEDY
Clean
condenser
High dew point
refrigeration compressor
operating?
ST thermostat tripped
Cooling air high tem-
perature
Excessive thermal load
(air fl ow, inlet temperature)
Fan pressure
switch (PV) not
set
Replace
pressure
switch
Z
Condenser
dirty or ob-
structed
Low current
absorption
No
refrigerant
recharge
Z
Low current
absorption
Request external
assistance
Decrease
cooling air tem-
perature
Decrease
compressed air
quantity tempera-
ture
Clean
condenser
Replace pres-
sure switch
Z
Replace fan
Z
HP pressure switch
tripped
Cooling air high
temperature
Excessive thermal
load (inlet air fl ow,
temperature)
Condenser dirty or
obstructed
Fan does
not turn (PV pres-
sure switch fault)
Fan fault
No No
No
No
No
No
No
No No
No
No
No
Yes Yes
Yes
Yes
Yes Yes
Yes
Yes
Yes
Yes
Yes
Yes
Lt Low evaporation
temperature alarm Ld
Low dew point alarm.
Low
cooling
air
temperature
Fan
always
working
(PV pressure
switch fault)
Replace
pressure
switch
Z
Hot gas
valve
not calibrated
Calibrate
valve
Z
Increase
cooling air
temperature
No
No
No
Yes
Yes
Yes
LP Low
pressure alarm
LP
Low pressure
switch fault
Yes
Replace
pressure
switch
Z
Liquid line
solenoid valve
closed
No
Replace
the coil
Z
Yes
No
High current ab-
sorption
Compressor
noisy
Compressor
components
perished
Condenser dirty or
obstructed
Repair or
replace
compressor
Z
Compressor
winding with
partial loss of
insulation
No
Yes
No
Yes
Yes
CP
compressor
thermal protection
alarm
The compressor
works in the op-
posite direction
invert
the phases
Yes
No
Compressor
fault
Yes