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R22-410 conversion questions.

Discussion in 'Commercial' started by otto, Jul 30, 2010.

  1. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    I have a request from the upper chain of command.

    Otto,

    Can you research about using a 410 condenser with an existing evaporator and lines? I understand that we will not achieve the condenser's efficiency but the real question is will we be losing capacity or creating undesirable running conditions, performance, etc? So far I have not been able to find this written anywhere but I'm wondering if maybe you can dig into this a little bit. What I want to do at ******** is replace the condensing unit, TXV, drier and flush the evaporator and refrigeration lines. Ultimately, my questions is can I do this without sacrificing capacity or endangering the new condenser.

    In all your spare time can you please look into this? :)

    Gino


    So here is the dilemma we have. A very old YORK 7.5 ton condenser is having a hard time.The fan keeps eating fan blades because the spider bracket is old, weak, rusted, welds broken and it is no longer available. This beast is 35 years old and ready for retirement.
    [​IMG]

    This is attached to a VERY old McQuay air handler, a beast of a unit and we don't want to replace the evap coil. Efficiency is not a concern, scientific analysis and quantum physics will be ignored. Will it work? We will use some RX-11 flush to get as much of the mineral oil out as we can. We will replace the cage & power head on the ALCO TXV, hopefully this is feasible.

    In my spare time....HA!:screwy: I have been busier than a 1-legged man in an ass kicking contest. More work tomorrow and I keep finding more work while doing the work that I don't have time to do.

    Oh, I did just get a nice raise so, the work is paying off.

     
  2. iron

    iron we men are wretched things

    Messages:
    13,326
    Location:
    central Florida
    the factory does not want you to mismatch
    but I have been changing 410a condensers and leaving the r-22 air handlers
    and just changing the ahu metering device
    been working great so far
    course I cant say what the efficiency is
    but ifin your cash strapped
    its been working so far
     
  3. Swampfox

    Swampfox red tagged

    Messages:
    34,501
    Location:
    Hell Hole Swamp
    Id try it

    so far Ive been successful getting away with stuff you arent supposed to do when it comes to 410a :D

    seriously though, it should be fine with the right TXV and as much of the old oil out as possible
     
  4. Okie

    Okie Go Balls Deep

    Messages:
    9,127
    Location:
    OKC,OK
    I would give it a try...Experiments are part of it.....
    If it doesn't work you have already got the condensing unit and a couple of steps from a total replacement anyhow......(thats the alternative that may be forced upon you anyway)
    Include in the bid maybe more than 1 TXV for experimental purposes.......
    I always like a good challenge.....:D
     
  5. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    Thanks, it's the "factory theory" and pissing matches that I want to avoid, that's why I don't spend much time "over there" any more.:banghead:

    I think it will work, too. Being more commercial, we're just starting to get into the 410 now that the 22 units are getting scarce.

    The money is not the factor, the size and location of the evap coil and that it's integral in the ancient air handler are the concern.
     
  6. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    The old air handler is from the 1960's when shit was built to last forever, so far it is running beautifully. If the fan bracket were available, this old condenser would also probably run for another 30 years. I just replaced the original contactor. It was arted at 40 amps but, looked like a modern day 90 amp heavy duty contactor!
     
  7. jpb2

    jpb2 Dog Tard *

    Messages:
    47,356
    Location:
    within the bounds of reality
    It's a pump and a radiator just clean it and the lines up well and make sure the nozzle matches the pump. Not ideal by any standard but it will probably work.
     
  8. zzonko

    zzonko New Member

    Messages:
    53
    We did a similar application at the beginning of last summer in hot humid Florida and it is humming along with no problems. Flush, txv, filter/drier. If there are any weak spots in the evap you will know soon enough.....so tell the owner that you make no warranty on that evap due to the higher pressure, are all the lines sil-fosed?
     
  9. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    All lines are brazed and ran in ACR rigid copper. LL drier and TXV equalizer are flared.
     
  10. dhvac

    dhvac best hung member

    Messages:
    2,342
    Location:
    New Stanton Pa.
    I would give it a go, obviously use the lowest efficiency unit you can find, new txv like you already said, you will know before you leave to first day if your readings are acceptable, weak spots may show later like stated but there is no reason it shouldnt work.
     
  11. frozensolid

    frozensolid Psychologist's Dream

    Messages:
    12,284
    Location:
    Earth
    Most manufacturers have a A/H conversion kit to take r-22 to 410a. Line size will not be a problem because 410a generally needs less line diam then R-22 and the higher pressures will move the oil.

    If they Don't make a retro kit to 410 for that unit be sure to change the distributor nozzle (orifice) when you change the valves. 410a uses a smaller nozzle.
     
  12. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    It's a TXV system with a big, flat coil. ALCO TXV with a 2-bolt assembly. We'll be replacing the TXV cage & power head. Old, heavy duty, sturdy coil.
     
  13. HMD

    HMD does it matter?

    Messages:
    93,375
    Location:
    here
    why can't they still build stuff to last?..........
     
  14. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    Because it never breaks! This whole ozone layer global warming and new refrigerants is all part of the tri-lateral commission plot to manipulate the economy.
     
  15. HMD

    HMD does it matter?

    Messages:
    93,375
    Location:
    here
    i understand. if it didn't break they wouldn't need a factory in china to make a new one
     
  16. DPSwitch

    DPSwitch Forget the hearse....

    Messages:
    64,158
    Location:
    Mid-Atlantic
    I know in refrigeration, test pressures can be alot lower on evaporators, like 150 - 200. What is the test pressure on the average AC evap designed for r22? I don't even know. If its less that 300, I don't know that I would want to do that.
     
  17. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    This is an old coil made back when they made things tough and made to last.
    Probably some pretty thick copper in the tubes. We're going full sped ahead with a caveat about the coil. I'm quite sure it won't be a problem. Thanks for the inputs and I'll be sure to post pics and let y'all know how it goes.
     
  18. DPSwitch

    DPSwitch Forget the hearse....

    Messages:
    64,158
    Location:
    Mid-Atlantic
    in that case it wouldnt bother me a bit...
     
  19. Okie

    Okie Go Balls Deep

    Messages:
    9,127
    Location:
    OKC,OK
    It may be more than that.....throw out tried and trued for some bullshit.....
    I don't understand.......:headscratch:
     
  20. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    the tri-lateral commission reference was a poor attempt at paranoid humor.
    Now that the TLC has been mentioned three times in one thread we're being watched.
    Get your aluminum foil caps on!