Basic Troubleshooting; Starting Problems; Oil Leakage; The Steps To Solving 95% Of All Problems - yellow jacket BULLET DCX NH3 Operation And Maintenance Manual

Basic Troubleshooting

Four Most Common Comments on
Pump Return Paperwork:
1. "Will not pump". This usually means
the pump will not pull a high enough
vacuum. This can be caused by valve
being left open, missing O-rings under
caps or contaminated oil.
SUGGESTION:
O-rings change oil twice and recheck
vacuum.
2. "Will not pull below 1000 microns".
SUGGESTION: Check for O-rings. Test
pump to determine actual pull down.
Remove all hoses and connect vacuum
sensor directly to pump.
3. "Noisy". Pumps are noisy when they
have not achieved a high vacuum. In
intermediate vacuum, there will be oil,
vane and exhaust noises.
SUGGESTION: Listen to the pump at
high vacuum. If relatively quiet, the
pump is running properly. If still noisy,
there may be a system leak.
4. "Repair and return". This is the most
difficult return comment to handle,
since we are unsure of what needs to
be done to keep the customer satisfied.
SUGGESTION: Be specific about the
problem with your pump if returning it.
Starting Pro ems
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• Be sure pump is plugged into live
receptacle with line voltage plus or
minus 10% of voltage on motor name-
plate. Long extension cords can greatly
reduce voltage and cause problems.
• Pump/oil temperature must be 30°F
(-1°C) or higher. Open intake to atmo-
sphere and switch on pump; run up to
speed before connecting to system.
Change valve
• Your BULLET
heavy-duty high torque motor for cold
weather starting, but dirty oil makes
starting more difficult, causing unnec-
essary wear on your unit.
• Dropping your pump can damage it. In
a locked pump condition, motor will not
run and the thermal overload will kick
out.
and
• Disconnect power cord and set pump
with front cover face down on table.
Reach into coupling area and try to
rotate the coupling. Do not use pliers
if the pump does not rotate, it is
"locked up."

Oil Leakage

• If leak develops between front and
rear half of oil case, tighten all screws.
Replace gasket if necessary.
• If shaft seal leaks, replace it.
• Wipe pump dry and watch for source of
leak. Tighten screws and repair.
The Steps to Solving 95%
of All Problems
1. Check oil level when pump is running.
It should be between the minimum and
maximum markings on the cover for
proper operation.
2. Check vacuum pump. Connect micron
gauge directly to the 1/4" port and
cap intake port. Turn on pump and
check vacuum reading. If reading is
good, check the system for leaks. OR,
if testing a system, isolate pump with
blank-off valve and get vacuum reading
from the pump alone. If the pump does
not pull and stay at a good vacuum
level, run until hot and change oil.
3. Check all flare connections. Make
sure they are tight.
DC Pump features a
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