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SEER 13 with SEER 10 combination

I couldn't get that link to work. Try this one:


  • krbudka2216612
    krbudka2216612 Member Posts: 2

    I have heard it is bad to match a new SEER 13 condensing unit with an older SEER 10 evaporator. Sometimes it is not practical or even possible to get a new air handler into an attic. Can anything really bad happen or is it just a matter of lost efficiency? Your thoughts please. Thanks, Kevin Budka
  • don_185
    don_185 Member Posts: 312

    Depends on what bad means to you.

    For me bads is.Using a old coil that could leak if not already leaking.Using a coil that is dirty all tho you can not see it with just looking at it.
    A system that has been install a mismatch known to void warranty with most manufacturer now days.

    A refrigeration inbalance that you are not sure what the superheat or subcool should be.

    However, if you want to take a chance and feel that you can make it work and be able to back it up..then I say, go for it.

    The question is, do you sell it as a 10 seer or, 13 seer or...I'm not sure what seer it is.
  • 13/10 SEER

    Will the system likely work? Yes. As Don mentioned, the question remains as to how well the system will work.

    The condition of the evaporator coil, the metering device used and the airflow through the coil will all play a role in determining the overall efficiency of the system.

    One way to determine the ballpark efficiency is to plot the system on a p-h chart and calculate all of the goodies associated with it. I am quite certain that, in the near future, you will be doing just that.

    On ARI's website, there is a prgram that allows you to enter the information for both the air handler and the condensing unit to obtain information regarding how well the mis-match will work.

    All the best.
  • Techman
    Techman Member Posts: 2,144

    Another way to look at it is,POSSIBLY,the metering device is not a "capillary tube type" and the old coil is not rated for 410a,then changeout the cond unit with a r22 cond unit.Change over to a TXV device. The seer would be somewhere between the two.It works in spots where you can't easily change out the evap unit.As long as r22 cond unit are available,that is !
  • Mark_46
    Mark_46 Member Posts: 312
    Cant Find


    Do you have a link for the tool that matches AH to condensors on ARI's site?

  • Ranger
    Ranger Member Posts: 210
    13 + 10 = 8

    There is an excellent article that was written in the August 2007 issue of the RSES Journal on page 21 by Brian Byrom on this subject. If you can find it,read it!
    [email protected] And on that note,I will leave you with this verbage excerpts from:
    York/JCI letter WS-008-06 dated July 20,2006

    "Specifically,ANY failed compressor claimed on a condensing unit with a SEER rating of 13 or higher WILL require the additional information about the MATCHED ARI RATED indoor coil or air handler before the contract will be approved"

    "Please note that UPG/JCI's warranty policy states that ALL equipment must be properly installed and maintained according to our published technical specifications. An "UNMATCHED" system is NOT compliant with our published recommendations and ALL future claims are subject to DENIAL."
  • Eugene Silberstein
    Eugene Silberstein Member Posts: 1,380
    Here is the link

    Here is the link:

    Have fun!
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