Chromatography Forum

Hi, I'm new here so be gentle. I have an Agilent 6890/5973 Inert GC-MS system that has come up with a new vacuum issue. I set it to vent the vacuum last night and this morning there was pump oil spraying out the top of the vacuum filter. The vacuum pump is an Edwards 1.5 and was VERY hot this morning. This is a new (refurbished) pump for my system, replaced last October. Any help would be appreciated. Many thanks.

Did the ms door pop open?
I have gone into vent to the point that the turbo has spun down and quads and source were cool. Left the rough pump pumping over a weekend with no issues.

The vent valve on the front wasn't open all night was it?

I don't imagine it was but doesn't hurt to ask.

Is the transfer line nut loose? When the metal cools it will contract and sometimes leak. Could also be a snapped column. Let us know what you find.

Hi, I'm new here so be gentle. I have an Agilent 6890/5973 Inert GC-MS system that has come up with a new vacuum issue. I set it to vent the vacuum last night and this morning there was pump oil spraying out the top of the vacuum filter. The vacuum pump is an Edwards 1.5 and was VERY hot this morning. This is a new (refurbished) pump for my system, replaced last October. Any help would be appreciated. Many thanks.

I am familiar with the Edwards vacuum pumps and filters, not so much with the GC-MS. I'm not sure what "vent the vacuum" means unless it means let the system up to atmospheric pressure. The problem sounds as though the vacuum pump may have been running at a high pressure all night. That would certainly cause the pump to run hotter than normal. Normal running is quite hot on these small pumps, I have one myself. If the pump was running at high pressure the air going through the pump would blow oil mist into the filter and overload the Mist element (green one) inside the EMF3 mist filter. The Mist element has a pressure safety valve in the top, if the filter material becomes overloaded it will cause a back presure in the pump oil box. If that back pressure gets too high the Mist element safety valve will relaes and allow the oil mist to blow right through the filter. That when you will see the oil mist (sometimes called smoke) coming right out of the top. You will need a set of new elements certainly. You can buy these at the lowest price, $85.00, with free shipping from our website www.vacuumandlowpressure.com. I hope that helps.

Yeah sounds like you told it to vent and were letting air in somehow, a few hours of running the ms with the sideplate door slightly ajar will take all the way to black and horrible looking (shouldnt do too much long term damage to the pump tho.)

The issue has been fixed, Agilent replaced the vacuum pump under a PM service contract. The service engineer doesn't know exactly what happens but he said he has seen it before. So, the outcome of this story is to...have a service contract. Thanks for your thoughts to everyone!