Sullair 20/12 500 CFM, Operator'S Manual And Parts List

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Section 6
MAINTENANCE
31
11. After maintenance, operate the valve a few times
to be sure of proper opening and closing. A metal-
lic click signifies that the solenoid is operating.
NEW SPRING INSTALLATION
When it is desired to change to a different form of flow
or operating conditions, new upper and lower springs
corresponding to the new requirements must be
installed. Depressurize valve and turn off electrical
supply. Remove the two (2) disc guide caps and old
springs.
Install new springs in their proper locations as indi-
cated on the factory labeled tags. Replace disc guide
caps and torque to 180 + in./lbs.(20 + 2 Nm). The
smaller diameter end of the Type “38” body springs
faces the discs.
NOTE
The lower spring is always the weaker of the two
and should always be located at the bottom. If the
springs are installed in the wrong position, the
valve will not function properly.
A method to determine which spring is the weaker is
by placing the two springs on the shaft of a screwdriv-
er or similar tool and compressing them. The spring
which compresses to the “L” dimension first is the
weaker of the two springs and should be placed on
the bottom.
6.7 TROUBLESHOOTING
The information in the Troubleshooting Chart is
based upon both the tests conducted at the factory
and the applied situations in the field. It contains
symptoms and usual causes for the described prob-
lems, however DO NOT assume that these are the
only problems that may occur. All available data con-
cerning the trouble should be systematically ana-
lyzed before undertaking any repairs or component
replacement procedures.
A detailed visual inspection is worth performing for
almost all problems and may avoid unnecessary
additional damage to the compressor. Always re-
member to:
S
Check for loose wiring.
S
Check for damaged piping.
S
Check for parts damaged by heat or an electrical
short circuit, usually apparent by discoloration or a
burnt odor.
Should your problem persist after making the recom-
mended check, consult your nearest Sullair repre-
sentative or the Sullair Corporation factory.
TROUBLESHOOTING
SYMPTOM PROBABLE CAUSE REMEDY
COMPRESSOR WILL NOT START Main Disconnect Switch Open Close switch.
Line Fuse Blown Replace fuse.
Control Transformer Fuse Blown Replace fuse.
Motor Starter Overloads Tripped Reset. Should trouble persist, check whether
motor starter contacts are functioning
properly.
Low Incoming Line Voltage Check voltage. Should voltage check low,
consult power company.
Defective Discharge Temperature
Thermistor Switch Replace probe and/or board.
COMPRESSOR SHUTS DOWN
WITH AIR DEMAND PRESENT Loss of Control Voltage Reset. If trouble persists, check that line
pressure does not exceed maximum operat--
ing pressure of the compressor (specified on
nameplate).
Low Incoming Voltage Consult power company.
Excessive Operating Pressure 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.
Defective pilot valve; pilot valve should cause
Sullicon Control to close the inlet butterfly
when the pressure switch contacts open.
Repair if defective.