Thermo Scientific EASY-nLC 1200 Troubleshooting And Maintenance Manual page 167

Weak or Absent Signal—Sample Not Aspirated
Thermo Scientific
A pressure drop at the start of the sample loading step indicates that pump S has introduced
air into the sample loop (see
When the method uses pressure to control the flow rate, the pressure should return to the
specified level within approximately 4 seconds after the sample is loaded onto the column. If
the pressure does not return to the specified level within approximately 4 seconds, pump S has
probably introduced air into the system.
Figure 123. Typical pump A profile for a system with air in the sample loop
Figure 123).
Pressure drop at the start of the
Sample Loading step
EASY-nLC 1200 Troubleshooting & Maintenance Guide
7
Troubleshooting
Troubleshooting Tips
145