Degasser Membrane Chamber — Sales and Instrument Support

Replacement membrane chamber for an online vacuum degasser. Mobile phase is passed through gas-permeable membrane tubing held inside an evacuated chamber; dissolved air diffuses out through the membrane wall before the solvent ever reaches the pump.

Degassing matters because dissolved gas comes out of solution wherever the pressure drops - at the pump inlet, and again in the detector flow cell after the column. Both produce symptoms that are easy to blame on other parts.

When the degasser is the real cause

• Baseline noise or sharp spikes that appear at the detector but not in the pump pressure trace.
• Pressure ripple and cavitation at the pump although the check valves are new.
• Retention times drifting through the first injections of a sequence.
• The vacuum pump running continuously instead of cycling, which points to a leaking chamber or a perforated membrane.

Each channel holds an internal volume of solvent, so after a solvent change the degasser has to be purged before the new mobile phase actually reaches the pump - skipping that step is a common reason a "changed" mobile phase behaves like the old one.