Sullair LS-12 Operators Manual And Parts Lists page 32

TROUBLESHOOTING (CONTINUED)
SYMPTOM
COMPRESSOR SHUTS DOWN
WITH AIR DEMAND PRESENT
(continued)
COMPRESSOR WILL NOT BUILD UP
FULL DISCHARGE PRESSURE
LINE PRESSURE RISES ABOVE
CUT---OUT PRESSURE SETTING ON
PRESSURE SWITCH
PROBABLE CAUSE
Low Incoming Voltage
Excessive Operating Pressure
Discharge Temperature Switch Open
Air Demand Is Too Great
Dirty Air Filter
Pressure Regulator Out Of
Adjustment
Defective Pressure Regulator
Leak In Control System Causing
Loss Of Pressure Signals
Defective Pressure Switch
MAINTENANCE
REMEDY
Consult power company.
Defect in pressure switch; check pressure
at which contact points open.
Separator requires maintenance; check
maintenance indicator under full load condi---
tions.
High pressure shutdown switch is adjusted
too low; readjust to 135 psig (9.3 bar).
Defective solenoid valve; solenoid valve should
cause control lever to move to unload stop
when the pressure switch contacts open.
Repair if defective.
Defective blowdown valve; blowdown valve
should exhaust sump pressure to 40 to
55 psig (2.8 to 3.8 bar) when maximum
operating pressure is reached. Repair if
defective.
Cooling water temperature too high;
increase water flow (water---cooled only).
Cooling water flow insufficient; check water
lines and valves (water---cooled only).
Cooler plugged; clean tubes. If plugging per---
sists, install water conditioner (water---cooled
only).
Cooling air flow restricted; clean cooler and
check for proper ventilation.
Ambient temperature is too high; provide
sufficient ventilation.
Low fluid level; add fluid.
Clogged filter; change the fluid filter element
and change the bearing filter element if
maintenance indicator shows red.
Thermal valve not functioning properly;
replace element (air---cooled only).
Water flow regulating valve not functioning
properly; change (water---cooled only).
Defective discharge temperature switch;
check for a short or open circuit to probe
and correct wiring.
Check service lines for leaks or open valves.
Check the filter indicator and change element
if required.
Adjust regulator according to control
adjustment instructions in the Maintenance
section.
Check diaphragm and replace if necessary
(kit available).
Check for leaks.
Check that diaphragm and contacts are not
damaged. Replace if necessary.
Section 6
27