Waters ACQUITY UPLC M-Class System Manual page 59

ACQUITY UPLC M-Class System troubleshooting: (Continued)
Symptom
Fronting peaks
(continued)
Missing peaks
Suspected cause
Column or pre-column is
contaminated
Column degraded forming
a void
Trap column degraded
Sample or standard is
degraded or contaminated
Wrong sample injected
Loss of resolution
Incorrect diluent makeup
Column conditioning or
re-equilibration problem
March 10, 2014, 715003588 Rev. A
Troubleshooting
Possible solution
Clean the column or
pre-column or replace.
The appropriate
See also:
column care and use guide
on the documentation CD.
Verify column
performance. If efficiency
is low, replace it.
• Remove trap column
and perform a direct
injection.
• If results are normal,
replace the column and
perform a set pressure
diagnostic.
• Inject a known good
standard.
• If the fewer peaks
problem persists, use
fresh mobile phase and
flush the system.
• If fewer peaks persist,
clean or replace the
column.
Check or replace the
sample.
Check the vial location
and location.
Check the diluent used for
preparing the sample.
Ensure the column is
adequately conditioned or
equilibrated.
59