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  1. #1
    Join Date
    Apr 2012
    Location
    central illinois
    Posts
    12

    Confused Vacuum pump shutdown

    I was in the process of vacuuming down a new R410a system and down to 340 microns when the vacuum pump tripped the breaker and lost power. By the time I got the hose valves shut off it had already drawn vacuum pump oil into the lineset. I disconnected gauge set, hoses and cleaned gauges and hoses with alcohol and used nitrogen to clean hoses. I also pressurized the lineset to 100 psi and removed all oil that i could by opening and closing hose valves. Reconnected pump and was only able to vacuum down to 1400 microns and held with no leaks. Added refrigerant for length of line set, opened condensor valves and started system. System seems to run fine, cooled well. Question is will oil in the refrigerant cause problems and if so how do I clean the system without damage to the compressor?

  2. #2
    Join Date
    Jan 2011
    Posts
    1,190
    Back when we were converting R-12 centrifugals to R-134a the first step was to remove all the mineral oil and replace it with POE oil. Run the system for a week and take an oil sample for testing. If the mineral oil percentage was less than 5% it was O.K. to proceed. If higher we had to change the oil again and run another week.

    How much oil do you think got into the system? How much do you think you removed? If the total left in the system is less than 5% of the oil that came in the compressor, you should be OK.

  3. #3
    Join Date
    Apr 2012
    Location
    central illinois
    Posts
    12
    Best guess on amount of oil would be 5 to 10 oz. When I sweeped the lines with nitrogen I removed most of it except just what is on the inside of the lineset. Thanks for the reply will definitely take the oil sample, just wasn't sure about the two different oils and how they would work together.

  4. #4
    Join Date
    Mar 2010
    Location
    Kent, WA.
    Posts
    189
    1400microns is a wee bit high for my tastes. escpecially if just evacuating a lineset and indoor coil.
    Experience
    Is what you get when you didn't get what you wanted.

    A positive attidude will not solve all your problems, but it will annoy enough people to make it worthwhile.

  5. #5
    Join Date
    Aug 2004
    Location
    North Richland Hills, Texas
    Posts
    14,915
    You either need to add an external check valve to your vacuum pump, or get a vaccum pump that has one built into it!

    Vacuum pump oil is not the same as refrigerant oil, I'm not sure how potentially bad it is for the system, but it can't be good for it.
    If more government is the answer, then it's a really stupid question.

  6. #6
    Join Date
    Dec 2011
    Location
    somewhere between here and there
    Posts
    478
    cmon...oil is oil....hehehehehe


    not.....

    ah...just let it run for a couple weeks......if you got a problem, its gonna show soon.....at that point, just claim warranty!!!!!!

    HAHAHAHAHAHAHAHAHAHA.....did i really just post that?


    Please, Please Please......keep the Factory Smoke in the Wires!!!!!


    Is it Rum'Oclock yet???

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