PRO-POINT 8682288 Manuel D'utilisation page 13

V1.0 30 GALLON TWO-STAGE TRUCK MOUNT AIR COMPRESSOR 8682288
make sure guard side is at least 18 in. away from the wall to provide adequate cooling of motor
and pump.
CHECK VALVES
Check valves are designed to prevent back-flow of air pressure in the compressed air system
(air flows freely in one direction only.) The check valve must be properly sized for air flow and
temperature. Do not rely upon a check valve to isolate a compressor from a pressurized tank or
compressed air delivery system during maintenance procedures! Always drain tank pressure
completely before attempting any maintenance or repairs.
MANUAL SHUT-OFF VALVES
Manual shut-off valves block the flow of air pressure in either direction. This type of valve can
be used to isolate a compressor from a pressurized system, provided the system is equipped
with a safety-relief valve capable of being manually released. The safety-relief valve should be
installed between the manual shut-off valve and the compressor.
SAFETY-RELIEF VALVES
Safety-relief valves aid in preventing system failures by relieving system pressure when
compressed air reaches a determined level. A check valve and safety relief valve are required in
all compressed air systems. Safety-relief valves are pre-set by the manufacturer and under no
circumstances should the setting be changed.
PILOT VALVE
Engine-driven units use a pilot valve instead of a pressure switch. It will discharge compressed
air to atmosphere or open the intake valve upon reaching a predetermined pressure setting.
See Maintenance - Pilot Valve Adjustment to calibrate the pilot valve.
PRESSURE VESSELS
ASME coded pressure vessels must not be modified, welded, repaired, reworked or subjected to
operating conditions outside the nameplate ratings. Such actions will negate code status.
PILOT VALVE ADJUSTMENT
RESETTING DIFFERENTIAL
Make sure the top toggle lever is positioned as shown in
Fig. 4. Loosen locknut (Fig. 4-1) by turning
counterclockwise several full turns. Gently turn
differential setting (Fig. 4-2) clockwise only until the
internal rod makes contact with the steel ball inside. After
making contact, turn differential setting counterclockwise
1/4 turn. Secure position by tightening locknut and
proceed to Top-End Setting.
TOP-END SETTING
Loosen locknut (Fig. 4-3) by turning counterclockwise
several full turns. Turning (Fig. 4-4) clockwise will
increase the top end pressure setting. Turning
counterclockwise will decrease the top end pressure
setting. Begin at a low setting by turning
counterclockwise one full turn. Proceed to fine tuning
instructions.
Fig. 5
FINE-TUNING INSTRUCTIONS
Start the engine and observe tank pressure gauge. As tank pressure approaches 100-130
pound-force per square inch gauge (PSIG), the pilot valve should begin unloading at the felt
muffler and cause the gas engine to slow down to idle speed.
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