Chromatography Forum

Has anyone found a suitable replacement for the junk Pfeiffer Duo 2.5 rough pumps that Agilent is using on the 5975 Mass Specs? We have 20 of those things and are having to replace them at an alarming rate. The shaft end seals leak after a few weeks, and others will just simply seize up. Even changing the oil out every two weeks is not making the problem any better. Surely there has to be an alternative.

Edit: I should add that we run these instruments much harder than most labs. We run 200 injections or so a day on each instrument over a 16-18 hour time frame.

The pump provided with previous generation MSDs was an Edwards 2.0. I'm not at the lab now, but we too have replaced one of the Pfeiffers with one of the older pumps from a 5973. What oil are you using? I was told by Pfeiffer that the oil provided with the pump was no longer suggested, rather something better was required.

Good luck.

I have tried the Edwards pump from a 5973, but it seems to be lacking performance. I do run the Edwards oil in the Pfeiffer pump and it does help a little, but not much. Agilent is shipping all replacement pumps with the Edwards oil now as well.

I run Pfeiffer pump with Inland 45 oil but this little pump produce a lot of noise and effectively leak easily

I have buy a fabulous pump, Varian DS102.....
Better vaccuum....with Pfeiffer, vaccum is 70, with Varian 45mtorr
No noise
Temperature of pump is 40celcius..for Pfeiffer, 85-90C
Less expensive

For Edwards pump.....is not better than Pfeiffer pump, lot of noise, high temperature and shaft seal leak regularly.

Progressively, i want to change all my pump for Varian DS102

As Rick said, the Varian DS102 pump is a great alternative. Very robust and also very quiet. The Pfeiffer pump mentioned above is very loud, the cage seems to magnify the sound.

There are Varian DS102 pumps for sale on eBay for under $1,000.

Thanks for the info. I will give the Varian a try.

I run Pfeiffer pump with Inland 45 oil but this little pump produce a lot of noise and effectively leak easily

I have buy a fabulous pump, Varian DS102.....
Better vaccuum....with Pfeiffer, vaccum is 70, with Varian 45mtorr
No noise
Temperature of pump is 40celcius..for Pfeiffer, 85-90C
Less expensive

For Edwards pump.....is not better than Pfeiffer pump, lot of noise, high temperature and shaft seal leak regularly.

Progressively, i want to change all my pump for Varian DS102

Rick,
how have you managed different flange diameters ?
Pfeiffer Duo 2.5 has flange dia. 16 mm and DS102 25 mm.

Is there enough air cooling for the pump? Is it under a open bench or closed?

I had never had any problems with this kind of pumps except when the temperature of the environment is above 40 C (40C under a closed bench not in the lab).

I run Pfeiffer pump with Inland 45 oil but this little pump produce a lot of noise and effectively leak easily

I have buy a fabulous pump, Varian DS102.....
Better vaccuum....with Pfeiffer, vaccum is 70, with Varian 45mtorr
No noise
Temperature of pump is 40celcius..for Pfeiffer, 85-90C
Less expensive

For Edwards pump.....is not better than Pfeiffer pump, lot of noise, high temperature and shaft seal leak regularly.

Progressively, i want to change all my pump for Varian DS102

Rick,
how have you managed different flange diameters ?
Pfeiffer Duo 2.5 has flange dia. 16 mm and DS102 25 mm.

There are adapters available. I just put an Edwards 3.0 on one as a test and had the same issue. The Edwards part number for the adapter is C10514437. You will also need one clamp and centering ring for both sizes.