- During flow, primary pump shows sporadic pressure drops
- Pressure drops from 8000 psi to 0 psi, and then rises again
- No flow from one or more solvent lines or pumps
- May appear as if the pump is leaking
- ACQUITY BSM
- ACQUITY QSM
Air in the solvent lines as a result of empty mobile phase bottles, or there is not enough solvent in mobile phase bottle
FIX or WORKAROUND
- Check the mobile phase bottles for all solvent lines.
- Ensure that the mobile phase bottle is full enough to completely cover the filter/sinker at the end of the solvent line.
- If buffer is used, place the lines in 100% water.
- Prime each line for 5 minutes, to ensure that the buffer is washed out.
- Place all solvent lines in 100% methanol.
- Prime all solvent lines for 5-10 minutes, or until any air bubbles dissipate.
- Start a flow with 100% methanol and monitor the pressure charts to confirm steady pressure.
- Switch to the mobile phase in use.
- Prime each line again for 5 minutes, to ensure that the methanol is washed out.
- Start a flow and monitor the pressure charts to confirm steady pressure.