Sullair ShopTek ST400 User Manual page 69

SECTION 6
Table 6-3: Troubleshooting Guide
SYMPTOM
Compressor will not start
Compressor shuts down
under service load conditions
Compressor shuts down
under service load conditions
- High Pressure Fault
Compressor shuts down
under service load conditions
- High Temperature Fault
PROBABLE CAUSE
Main disconnect switch open
Line fuse blown
Motor starter overload tripped
Low incoming line voltage
Loss of control voltage
Low incoming line voltage
High operating pressure
Compressor pressure setting
incorrect
Control line strainer clogged
Minimum pressure valve
malfunction
Control line air leak
Defective unload solenoid valve
Cooling air flow restricted
Ambient temperature too high
Low fluid level
Clogged fluid filter
Thermal valve malfunction
Temperature sensor RTD
malfunction
Cooling fan rotational direction is
reversed.
02250180-090 R00
S T
™
HOP EK
REMEDY
Close switch.
Replace fuse.
Reset - if fault persists, check motor
contacts for proper function.
Check voltage - in the case of low voltage,
check power source, or contact local power
company.
Check 110V AC power supply.
Check voltage - in the case of low voltage,
check power source, or contact local power
company.
Reset - if fault persists, check line pressure
and ensure that it does not exceed the
compressor's maximum operating
pressure.
Change setting in Controller.
Clean or replace strainer.
Repair or replace minimum pressure valve.
Repair leak
Check valve – if it does not operate when
energized, replace the valve coil or the
entire valve if defective.
Clean cooler and check for proper
ventilation.
Check ventilation and increase if too low.
Add fluid.
Change the fluid filter element.
Replace thermal valve element.
Check connection and sensor – replace if
sensor is defective.
Reconnect fan motor cables for proper
rotational direction.
USER MANUAL
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