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  1. #1
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    Vacuum pump overheating

    Not generally a bigger is better person..., but

    I've been using a 1.7 CFM Bacharach vacuum for the last year. My thought was that I generally work on small systems under 7.5 tons. So, I didn't need a big machine.

    The problem this season has been that in the 104˚ temps we've been having my little pump will shut down right as it is getting to 500 microns, and that sends me jumping for the VCRT's to shut the valves before oil gets sucked out of the pump.

    Will a bigger pump help avoid over heating, or do i need to go to something like the TEZ8 which seems like overkill for what I do?
    It's an upside down world we live in.

  2. #2
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    Is that a 1725 or 3600 RPM?

  3. #3
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    Thread Starter
    Quote Originally Posted by skwoodwiva2 View Post
    Is that a 1725 or 3600 RPM?
    It is a QV2, 1720 RPM, 1/4 HP
    It's an upside down world we live in.

  4. #4
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    Get a JB 3.

    So your motor is going out on thermal.
    Try monitoring your inches & keep the pump at 20 to 25 on initial pull down. This is a good practice with any pump that has no oil pump. Our pumps use vacuum to get oil into the low stage rotor.

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  6. #5
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    I have a $49 Harbor Freight 2.5 CFM I use in my shop for recovery tanks, it kits A$$!

  7. #6
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    Thread Starter
    Quote Originally Posted by skwoodwiva2 View Post
    Get a JB 3.

    So your motor is going out on thermal.
    Try monitoring your inches & keep the pump at 20 to 25 on initial pull down. This is a good practice with any pump that has no oil pump. Our pumps use vacuum to get oil into the low stage rotor.
    Help me understand this. Are you suggesting to somehow slow the initial vacuum by regulating through a gauge?
    It's an upside down world we live in.

  8. #7
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    Quote Originally Posted by David Goodman View Post
    Help me understand this. Are you suggesting to somehow slow the initial vacuum by regulating through a gauge?
    That's what yj reccomends. Pull the hoses down first then slowly open the valves on the crt

    Sent from my SM-S727VL using Tapatalk

  9. #8
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    No gauge set please, use a BValve on the pump & a dedicated vacuum hose set. Use your gauges on a port on that larger manifold. But do not pull through your gauges.
    But yes.

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  11. #9
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    Thread Starter
    Here is what I have been doing.

    1/2 " Appion hoses to VCRT's on high and low side. Start pump with valves closed and ballast open. Let run for a minute or so, and then close the ballast.

    Run with valves closed until vacuum changes its sound. Then open the VCRT valves all the way.

    Let me know if there is something I should change.
    It's an upside down world we live in.

  12. #10
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    We use the TEZ8... literally NEVER have any issues with it.
    It weighs 28#... which is less than some of the conventional design pumps I have owned.

    I change the oil cartridge (yeah, that is one seriously neat feature!), probably twice a month during the summer and once a month the rest of the year (note we have mostly gas heat in my area).
    I bought a 3 pack of the cartridges and a gallon of Appion pump oil (BTW: Appion pump oil is NOT near as hydroscopic as most vacuum oils are). When I am down to the last clean oil cartridge, I dump and clean out the dirty ones. Thinking to get another 3 pack, so I will not have to do it as often.

    Note: The pump pulls a GREAT vacuum on the old cartridge and on the new cartridge... so one does not need to change the oil near as often.

    The pump is 5+ years old... literally NO issues at all!

    It is an 'investment'... however it could well be a longer term investment...
    Ga-HVAC-tech

    Your comfort, Your way, Everyday!

  13. #11
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    Quote Originally Posted by David Goodman View Post
    Here is what I have been doing.

    1/2 " Appion hoses to VCRT's on high and low side. Start pump with valves closed and ballast open. Let run for a minute or so, and then close the ballast.

    Run with valves closed until vacuum changes its sound. Then open the VCRT valves all the way.

    Let me know if there is something I should change.
    The GB does not matter on start, it is for when you are starting to pump water vapor.
    Good, just keep your low gauge between 20 & 25" then open it up when it will not fall lower while open.
    The smaller the pump the more this is vital.
    I have left a JB 3 on a 100 ton system, over a WE, cause other pumps were not available. But starting early enough in the day & throttling , it was ok. It took all day to get to 25" but once there, good. It was at 300 mics on Tuesday.

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