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9
SYMPTOM
PROBABLE CAUSE
SOLUTION
Prewet solvent overflows.
Incorrectly set Thermistors
Use the Thermistor Height Tool
to ensure the recommended
height is set.
Pressure is set too high.
Verify the nitrogen source
pressure is set correctly.
Verify that the Solvent Bottle
Pressure is set correctly.
Bad Thermistors.
Replace the Top Thermistor.
Prewet solvent is not drained.
Insufficient vacuum.
Verify that the vacuum source is
set correctly.
Verify that the Water-Waste
Carboy Manifold is correctly
seated.
Close the Water-Waste Carboy
Drain.
Verify the Solvent Waste vacuum
is set correctly.
Solvent-Waste valve is not
opening.
Write a short method with only 1
prewet in it and run. Replace
valve if no actuation is seen.
Prewet solvent is drained
immediately.
Waste valve is stuck open.
Place DI Water into Disk Holder
attached to a module. Watch
the waste containers and
identify which one the water is
pulled into.
Check Valve is stuck open.
Use the Check Valve Tool to
cycle the Check Valve. Place DI
Water into a Disk Holder
attached to a Module. Replace
Check Valve if necessary.
Extractor continually drains after
first Prewet.
Incorrectly set Thermistor.
Use the Thermistor Height Tool
to ensure the recommended
height.
Thermistors heights reversed
Verify that the higher of the two
Thermistors is connected to J6
on the Control Circuit Board.
Bad lower Thermistor.
Replace Thermistor.
Prewet solvent drips from the
Downtube.
Prewet valve stuck open
Increase the Solvent Bottle
Pressure to 17 psi and run a
method that fires only the
affected valve. Replace the valve
if necessary.
Sample does not dispense.
Low/No pressure.
Verify that the nitrogen source is
set correctly.
Verify that the Extractor
Pressure is set correctly.
Water Inlet Valve Actuator is
Increase Extractor Pressure to
Summary of Contents for SPE-DEX 4790
Page 1: ...SPE DEX 4790 Solid Phase Extraction System Service Manual ...
Page 6: ...5 Notes ...
Page 39: ...38 ...
Page 47: ...46 ...
Page 59: ...58 8 Schematics 8 1 Nitrogen and Solvent Delivery System ...