Troubleshooting Guide

8
QS5 Operating Manual
9.0 Trouble-Shooting
Problem Possible Cause Remedy
Does not achieve
good vacuum
1. Loose/open fittings
2. Not enough oil
3. Dirty/contaminated oil
4. Old/dirty/non-vacuum
rated hoses
5. Gas ballast open in
deep vacuum operation
6. Pump has reached the
end of its useful life
1. Make sure all
connections are tight, gas
ballast & oil fill cap are
closed and unused inlet is
not open.
2. Add oil to level indicated
3. Change oil
4. Use new hoses rated for
deep vacuum
5. Close gas ballast
6. Service or replace pump
Oil discolored 1. Excess moisture in oil,
or oil burnt
1. Change oil
Oil leakage 1. Loose
fittings/connections
2. Over-filled with oil
1. Ensure oil drain and
related fittings are tight
2. Check oil level, drain
extra if necessary
Failure to start 1. Power disconnected
2. Thermal protection
has shut pump down
3. Cold start condition
4. Operating voltage too
low
5. Power supply cord too
long
6. Foreign matter has
entered pump
7. Blown fuse
1. Connect power
2. Allow pump to cool, will
re-start on its own
3. Subject pump to heat to
raise the ambient
temperature
4. Check operating voltage
5. Use shorter power supply
cord
6. Check and clean pump
7. Check fuse (near power
receptacle) and replace if
necessary.