AADCO 737 Series, Operating Instructions Manual

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reaches 80-psig and the pressure switch cuts off power to the
compressor. This should occur within thirty seconds if the starting input
pressure were at 60-psig and within two minutes if at zero. See Section
14.0 for proper adjustment of this setting if not at 80-psig and 60-psig.
13.5
Continued.
(b) While performing tests in (a) above, it is a good time to check for any
leaks developed between the compressor and the input to the purification
reactor by checking all of the fittings between them with soap solution
WHILE THE COMPRESSOR IS RUNNING and the lines are under
pressure. This includes all connections on the ballast tank, the
compressor hoses, and the tubing leading to the INPUT PRESSURE
gauge, as well as the tubing leading to the input of the purification reactor.
Any leaks will make it appear as though the compressor is not operating to
capacity.
(c) A check should be made of the compressor pop-off valve, Figure 8 (48).
Air should not be coming from the valve when the input pressure is below
100-psig. If there is, the valve should be adjusted to eliminate the
leakage. Use a _-inch wrench to loosen the locknut at the end of the pop-
off valve and a ½-inch wrench to turn the adjustment nut clockwise to
increase the pop-off pressure setting. Once the air leakage has been
stopped, tighten the _-inch locknut while holding the ½-inch adjustment
nut securely to avoid changing its setting. Should it be impossible to stop
the leak, replace the pop-off valve with one which has been pre-set. See
Section 18, Parts List.
13.6
IF THE COMPRESSOR CONTINUES TO RUN AFTER THE INPUT
PRESSURE REACHES 80-PSIG AND THE INPUT PRESSURE CONTINUES
TO RISE BEYOND 80-PSIG, THE PROBLEM LIES WITH THE SOLID STATE
RELAY.
(a) Depress the PUMP switch to off position. If compressor continues to run,
replace solid state relay which is shorted.
(b) If voltage present at terminal #4 of solid state relay even when input
pressure is above 80-psig, the pressure switch is defective. Make
adjustments to switch as in Section 14.0 or replace with new pre-set
pressure switch, making connections as on old pressure switch.
13.7
IF COMPRESSOR CONTINUES TO RUN AFTER THE PUMP SWITCH IS
DEPRESSED TO THE OFF POSITION: