Gilson VERITY 1910 MS User Manual page 73

Symptom/s
No signal; no spray current
Drop in ion signal to zero
counts; capillary current
increases
Severe drop in TIC
background accompanied
with no signal for late eluting
peaks in an HPLC reverse
gradient chromatograph
Severe fluctuations in the
spray current, especially when
spraying a solution with a high
aqueous content
Spray current fluctuations
increase under fixed
conditions
Ions are in the wrong m/z
position
Base pressure is too high, or
there is insufficient vacuum in
the ion guide and analytical
chambers
Possible cause
No sample flow
Capillary tip may be clogged.
A voltage cannot be applied
to the spraychip assembly
because the interlock is
engaged.
A droplet has formed inside
the spraychip assembly.
The vac-chip is clogged.
There is an electrical short
within the spraychip.
Capillary tip may be dull or
clogged.
A leak in the tubing.
System is not calibrated or
auto tuned, or has lost its
calibration.
O-rings may be leaking.
Vacuum pump exhaust tubing
is restricted or blocked.
Vacuum pumps may require
replacement.
Remedy
Check liquid connections and sample flow
from the syringe pump/LC to the spraychip
assembly.
Change the spraychip. Refer to
Remove the spraychip on page 55.
Make sure the front door is fully closed.
Ensure that no sample is flowing through the
system. Increase the flow rate of the nebulizer
gas to 5 L/min. Enable the high-voltage supply
and increase the capillary voltage. Run the
system under these conditions for 15 minutes.
Use a higher nebulizer flow rate if the problem
persists.
Replace the spraychip. Refer to
Remove the spraychip on page 55.
Replace the vac-chip. Refer to
Remove the vac‑chip on page 50.
Reduce the spraychip tip voltage.
Stop the sample flow and increase the nebulizer
gas flow for five minutes. Restart sample flow.
Change the spraychip. Refer to
Remove the spraychip on page 55.
Replace the spraychip. Refer to
Install the spraychip on page 57.
Check all fluidic connections.
Follow the procedure to calibrate the
VERITY 1910 MS Detector. Refer to
Chapter 3 | Auto Tune (Calibrate).
Contact Gilson. Refer to
Customer Service on page 12.
Ensure that the tubing is free from any
restrictions.
Contact Gilson. Refer to
Customer Service on page 12.
VERITY® 1910 MS DETEcToR
73
| USER'S GUIDE