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  1. #14
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    Quote Originally Posted by BennyD View Post
    Ok, one last question and I'll stop bugging you. Does it cool enough to let the pump run flat out early in the vapor process? I would imagine it could, due to the time frame you run.
    Again, thank you!
    Take a look at the curb of any pump and you'll see the answer to your question, if you are asking about the effect of reducing vapor volume.
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  2. #15
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    Quote Originally Posted by valdelocc View Post
    Take a look at the curb of any pump and you'll see the answer to your question, if you are asking about the effect of reducing vapor volume.
    I was asking more on the line of if the condenser was able to condense the vapor fast enough to keep the discharge of the pump from going positive.

    Stop, step back, relax and have another go at it.
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  3. #16
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    Quote Originally Posted by BennyD View Post
    I was asking more on the line of if the condenser was able to condense the vapor fast enough to keep the discharge of the pump from going positive.
    Thats a good question and haven't thought about it, the discharge pressure would be dictated by the ambient temperature surrounding the recovery tank.
    There is not better place for the working men than the union! 100% UA the only HVAC union!

  4. #17
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    Quote Originally Posted by valdelocc View Post
    Thats a good question and haven't thought about it, the discharge pressure would be dictated by the ambient temperature surrounding the recovery tank.
    That and the temp of the liquid leaving the condenser.. at least for a while until the tank acclimates to room temp like you stated.
    Thank you for all your input. Greatly appreciated!

    Stop, step back, relax and have another go at it.
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  5. #18
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    When I used to do this, there were times I would have to throttle the pump inlet to prevent pressurizing the tank too much. But it was usually for a relatively short time. Maybe an hour at most. Then I could open the valve all the way.

    Meant to quote post 15 on this.

  6. #19
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    Quote Originally Posted by Nuclrchiller View Post
    When I used to do this, there were times I would have to throttle the pump inlet to prevent pressurizing the tank too much. But it was usually for a relatively short time. Maybe an hour at most. Then I could open the valve all the way.

    Meant to quote post 15 on this.
    I was curious. I know those Welch pumps don't like much pressure on the discharge side. Thanks

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  7. #20
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    Pulling vapor is the biggest pain in the ass going, obviously if the machine is tight it's a whole easier. My stuff is all home made as well, I use a Welch 15 cfm duo seal without a separator and a water cooled condenser, after pushing all the liquid I pull Vapor off the top of the chiller into the suction of my pump from there into the water cooled condenser and into the bottom of the tank.

    I hang the water cooled condenser above the tank and allow the condensed refrigerant to fall into the tank. I try and find the coldest water i can get, if they have a chiller running I use chilled water and throttle the inlet to the pump to try and keep my tank pressure down.
    You know your a stud in the bedroom when the girl your raping comes before you and the cops

  8. #21
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    Just wanted to give an update. I was talking to one of our other guys. He wants to build a vapor recovery unit using a shell and tube hx with a small chilled glycol unit, running possibly to 0 degrees Fahrenheit. It will be a small packaged unit on wheels.
    The only issue is that it'll hold liquid when recovery is done. When we get busy, our units get shipped out to another job once recovery is done. I suggested a reversing valve to heat up the glycol to boil out the liquid.
    The only issue with this is we planned on using hot gas bypass to keep the compressor from cycling when we get deeper in a vacuum in the chiller.
    Has anyone see hot gas on a heat pump setup? Only enable it when in cooling mode? I'm not sure if it even can be done.

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  9. #22
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    Do you guys use homemade recovery drums
    If so do you add a prv?

    I'm building up a couple with valves and dip tube

  10. #23
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    Quote Originally Posted by DLR_LWT View Post
    Do you guys use homemade recovery drums
    If so do you add a prv?

    I'm building up a couple with valves and dip tube
    No, we still use the old tan Trane "mushroom" 750# tanks. They have round sight glasses near the top on bottom. 1/2 glass in top is roughly 750#. Have a couple 1000# recovery tanks as well.

    The only thing with the Trane tanks is that they are not DOT. Can't transport if there is any R123 in them, R11 isn't regulated.

    I don't like dip tubes on large tanks, I believe they restrict flow. I like valves on top and bottom better.

    All tanks do have a PRV on them. I think it's a cheap piece of insurance. PRV or a lot of refrigerant... let alone the possibility of questions.

    Home made is fine if you just plan on storing on site. If transporting, need to get them certified. Hate to run into a DOT check!

    Stop, step back, relax and have another go at it.
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  11. #24
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    Quote Originally Posted by DLR_LWT View Post
    Do you guys use homemade recovery drums
    If so do you add a prv?

    I'm building up a couple with valves and dip tube

    With a few custom changes, empty 650LB r-123 drums are fine for recovering, just be careful not crush it while re-charging.
    There is not better place for the working men than the union! 100% UA the only HVAC union!

  12. #25
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    Quote Originally Posted by DLR_LWT View Post
    Do you guys use homemade recovery drums
    If so do you add a prv
    So what hapens when the home made rig or drum goes kaplewwee and spills refrigerant down the drain etc and then labor inspectors and goverment types get involved and want to know who and where and why were you using unapproved uninspected untested etc etc equipment ....
    Whos ass is grass then ?
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  13. #26
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    No, we still use the old tan Trane "mushroom" 750# tanks. They have round sight glasses near the top on bottom. 1/2 glass in top is roughly 750#. Have a couple 1000# recovery tanks as well.

    The only thing with the Trane tanks is that they are not DOT. Can't transport if there is any R123 in them, R11 isn't regulated.

    I don't like dip tubes on large tanks, I believe they restrict flow. I like valves on top and bottom better.

    All tanks do have a PRV on them. I think it's a cheap piece of insurance. PRV or a lot of refrigerant... let alone the possibility of questions.

    Home made is fine if you just plan on storing on site. If transporting, need to get them certified. Hate to run into a DOT check!

    Stop, step back, relax and have another go at it.
    By the way those Trane tanks hold 650lbs. roughly at the sight glass, depending on room temp and type of refrigerant. Listed in RRPA-IOM-1

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