Agilent 1200 Quat pump won't prime

[BrianJR]

I'm having a problem with our Agilent 1200 Quaternary pump. When I try and pump any liquid through channel D, all I get is air. I've tried different solvents (water, ACN, Isopropyl) and I've tried different pump configurations (ie 100% D, 50/50 A/D etc) and there is no change. This channel has received almost zero use since we bought the instrument (~2 years ago).

I'm wondering if the pump may need new seals. It has seen minimal use since we got it (~300 injections) and has sat for extended periods, however always flushed with 50:50 water/ACN. I would appreciate any suggestions!

[Kimico]

Good morning.

Chances are there is a big plug of air in between your D channel. More than likely you will have to prime the channel D manually with a syringe fitted with a luer adapter.

[BrianJR]

Thanks Kimico. Do you mean priming the pump by drawing solvent through the pump itself? Won't that damage something? I've tried priming the clear line leading from the degasser into the pump and letting the system run for ~30min with no luck.

[bisnettrj2]

Agilent recommends not using the pump to prime an empty channel, so you do need to get solvent to the pump first. Use isopropanol on the D channel, and use the Luer-lock syringe to get the air out of the degasser. Once you've got a free flow from the degasser, then connect the line to the D channel. Open the purge valve, set the flow to 5 mL/min, and you should be primed within a few minutes, if not less.

[HPLCCONSULT]

The Pump is fine. No need to use syringe. Fine to run solvent through entire system.

(1) check to make sure that the low pressure fittings from the 'D' bottle line to the degasser are snug. Check to make sure the 'D' line fitting from the degasser to the pump MCG Valve is snug.
(2) Bottle 'D' full of solvent (IPA, ACN, MeOH are all fine).
(3) Set channel 'D' for 100%.
(4) Set high pressure alarm for 150 bars (less than 200).
(5) Open Prime Purge valve one turn.
(6) Set flow rate to 9.999 ml/min.
(7) Turn pump 'ON'.
(8) Wait for liquid to purge out air. Depending on which degasser you have, this could take awhile. Example: Std Degasser has ~ 10 ml volume per channel plus 5 mls per line (2x) so 20 mls volume. At 10ml/min = 2 minutes.

*If this does not work it is possible that your MCV proportioning valve has one bad 'D' soleniod (very rare on such a young unit). Sometimes the seal will stick when not used or when used with dry solvents such as Hexane for long periods of time. This too can usually be "fixed" by allowing the line to stay in IPA for a few hours to rehydrate the seal back.

[Consumer Products Guy]

Good morning.

Chances are there is a big plug of air in between your D channel. More than likely you will have to prime the channel D manually with a syringe fitted with a luer adapter.

This is what I'd do as well, get liquid flowing out the D tube, then screw the D tube into the multi-channel mixing valve.