6
Troubleshooting
Troubleshooting Guides
118
Accela 600 and 1250 Pump Hardware Manual
Thermo Scientific
Degasser Troubleshooting Guide
lists symptoms you might observe with the degasser, probable causes of the
symptoms, and corrective actions.
Table 19.
Degasser health check and troubleshooting guide
Symptom
Probable cause
Solution
Amber status LED is on steadily,
pump is running, and RPM seems
high.
Pump is in start up phase or system’s
degassing demand has increased.
If the vacuum pump speed continues to
rise for an extended period of time (as
heard by the pitch of the stepper motor),
it might indicate a potential fault
condition.
Amber status LED is flashing
approximately 1 second off,
1 second on. Vacuum pump is not
running.
Possible leak.
Contact your Thermo Fisher Scientific
field service representative.
Amber status LED is flashing
approximately 2 seconds off,
1 second on. Vacuum pump is not
running.
Possible sensor or control board
fault.
Contact your Thermo Fisher Scientific
field service representative.
Power and Vacuum LEDs
illuminate green, but the pump
cannot be heard.
Due to the design of the pump and
degasser, the pump is very silent at
low RPMs, even though vacuum is
good and degassing is normal.
Monitor the UV absorbance of
non-degassed methanol at 215 nm
versus degassed methanol coming
through the degasser. Proper
performance of the degasser should
decrease the UV absorbance of the
methanol significantly.
Bubbles move through the output
tubing.
Loose fitting or fittings.
Tighten the input and output fittings.
No solvent flow.
If a buffer was left in the degasser for
some time after use, it might plug
the degasser.
Prime/purge the pump head.
Use a different channel, or connect the
channel to a beaker of the solvent
without the buffer. Draw the solvent
through the channel to dissolve the
buffer. Do not push the solvent through
the channel. If this flushing action does
not work, contact your Thermo Fisher
Scientific field service representative.
