HPLC pumping air

[Sdwn]

Hi. This is my first time experiencing this issue. My solvent runs dry and my HPLC has been pumping air for over a day(it's been running during the weekend). I panic and re-filled the solvent and i start purging the air out. Will my column and HPLC spoil? What should i do?

[Steve Reimer]

It happens. If the pump seals are OK, purge the air out and proceed.
Once air hits the pump heads pumping stops, even if the pumps don't.

[tom jupille]

To expand a bit on Steve's comment:

Running the pump dry for an extended period of time *can* damage the seals. The only way to tell for sure is purge the system and then run it. If you're paranoid, you can do a "leak-down" test (blank off the outlet line from the pump, set a reasonable high pressure cutoff, run the pump until it cuts off, then monitor the pressure; if the pressure drops more than about 15% over 15 minutes, the seals should probably be replaced).

The column is probably OK and should work after you purge the air out. As Steve indicated, *most* pumps are not able to pump air. That said, years ago I had an Altex 110 which *could* pump air and yes, my column was ruined

[Ice9]

On acquity H-class, if using multiple lines (3 in my case) one ran dry and continued pumping, because the other pumps had solvent it pumped air onto the the column and trashed it.