US VACUUM Torrvac Series, Installation & Operation Manual

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TROUBLESHOOTING
TROUBLE
The pump does not reach “blank-off” pressure
or takes too long to evacuate the system.
Possible cause : Contaminated oil is the most
common cause of not reaching ultimate pressure.
Remedy : Shut off the pump, after the operating
temperature has been reached, drain the warm oil
from the pump and change the automotive type oil
filter (where applicable), if necessary. Flush and fill
the pump with new oil and take a new “blank off”
measurement after operating temperature is
reached (20-30 minutes).
Possible cause : The vacuum system or vacuum
piping is not leak tight.
Remedy: Check the hose and pipe connections for
possible leak.
Possible cause : The wire mesh inlet screen is
plugged.
Remedy : Clean the wire mesh inlet screen. Install
an inlet filter if the problem repeats frequently.
Possible cause : No oil or not enough oil in the oil
reservoir.
Remedy : Shut off the pump, add the necessary oil,
or if oil seems contaminated, drain the balance of
the oil from the pump, exchange oil filter and refill
with fresh oil. Flush if necessary.
Possible cause : Automotive type oil filter clogged.
Remedy : Replace oil filter. Change oil if necessary.
Possible cause : The inlet anti-suck-back valve
plate (ref#129) is stuck closed or partially open
position due to contamination.
Remedy : Disassemble and clean if necessary.
Possible cause : Oil tubing fittings are loose and
leaking.
Remedy : Replace or retighten the oil fittings or
oil tubing.
Possible cause : Shaft seal is leaking.
Remedy: Replace the shaft seal.
Possible cause : Exhaust valve (ref#145) is not
properly seated or it’s partially stuck open.
Remedy : Contact U.S. Vacuum for instructions.
Possible cause : Vanes are stuck in rotor or
otherwise damaged.
Remedy : Free vanes or replace with new ones.
Contact U.S. Vacuum for instructions.
Possible cause : The radial clearance between
rotor and cylinder is no longer adequate.
Remedy : Contact U.S. Vacuum for instructions.
Possible cause : The internal parts are worn or
damaged.
Remedy : Contact U.S. Vacuum for instructions.
Possible cause : Oil tubing fittings are loose and
leaking.
TROUBLE
The pump will not start
Possible cause : The motor does not have the
proper supply voltage or is overloaded; the motor
starter overload settings are too low or are the
wrong setting; fuses burned; or the wire is too
small or too long; causing a voltage drop at the
pump.
Remedy : Check correct supply voltage; check
overload settings in motor starter for size and
setting according to motor nameplate data; check
fuses; and install proper size wire. If ambient
temperature is high, use larger overloads or ad-
just settings 5% above nominal motor nameplate
value.