continuous peaks with waters 2487 detector

[pri6886]

Hello,
I am using the Waters 2487 detector and 717 sampler to analyse my compound since last 1 month.

I had given the machine to another student to use for 2 days and then restarted it today (using same column).
My problem is that even after equilibrating it for an hour I am seeing continuous peaks in the equlibration chromatogram. The peaks are one after the other. All of same size and same shape. The peaks are about 5-6 minutes broad!!!

I dont know what to do. I never had this problem in the ;last one month.

But another friend of mine used this machine 4 months back and encountered same problem (on a different column though) which means if there is an error its with the machine..
Please help.

[bbcmouli]

your pump may gone bad, check plungers

[DR]

Before digging into the pump, I'd egt out a stopwatch and small graduated cylinder. Check flow rate, if it's bad, you probably have a stuck check valve. This may also be indicated by a high delta (fluctuations in pressure).