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Vac Pump Testing

If you are just testing to see if the pump pulls down by evacuating, for example, a gauge manifold, the pump should be able to pull all the way down to 50 microns.

As we had discussed a while back, Mike, changing the oil prior to testing is a good thing to do, especially if, as another tech noted, there is only one pump being used for 5 technicians. One never knows when the last oil change was done.

As a quick service note, guys, be sure to replace the vacuum pump BEFORE each use, not after. Moisture-laden oil will reduce the pumping capacity of the unit.

You guys ahould also check out the new APPION vacuum pumps. They feature a 5-second oil change as the oil comes in easy-to-remove, easy-to-replace cartridges.

Check them out at www.appioninc.com


  • Empire_2
    Empire_2 Member Posts: 2,343
    Running a vac test on pumps.

    What are you guy's testing your vacuum pumps down to when testing for the summer season? I usually try to get it down to 500 mic's or so. Is this enough?
  • jim lockard
    jim lockard Member Posts: 1,059

    just on the test with the Vacum pump alone I can get 50 microns or better. On a tight new system we try for 300 microns or better Mike. Best Wishes J.Lockard
  • Techman
    Techman Member Posts: 2,144
    Vacuum Pumps

    Greetings.We use our vac pumps all year long,doing refrigeration service,so,we test our pumps by using them on a regular basis.I did work for one company that had one vac pump for five mechanic's, the pump sat on the shelve,in the shop until it was "needed" by one of the mechanics By the way ,350-500 micron's is ok. How long does it to pull a proper vacuum? Is the vacuum reading at the vacpump{usually connected to the condensing unit} the same as the vacuum reading at the evap coil 80-100' away?
  • jim lockard
    jim lockard Member Posts: 1,059

    We only do hvac with R-22, most system piping does not exceed 50 feet at the most, so to pull a 350 micron vacum and allow it to stand for 3 minutes for a maxium rise of 500 microns is more then good its great. Best Wishes J.Lockard
  • RadPro
    RadPro Member Posts: 90
    Vac pump test


    When I was getting started in IL, I bought a new J/B pump. Used it quite a bit, but could not get it to go below 1000 microns. Took it in to J/B days so the factory rep could test it. Put it on a 50lbs recover cylinder and it pulled 50 microns. I told him I would try again as I was putting in a new split system, clean & dry tubing with new evap coil. Pulled 1000 microns and I had let it run a long time. Sent it back in and they found a problem with the impeller.

    Always use a micron guage and you will know if your pump is working right!(But do I do it!?!)

    Don in IA
  • Eugene Silberstein
    Eugene Silberstein Member Posts: 1,380
    Of Course

    Of course you do it, Don. Don't we all?
This discussion has been closed.