Results 1 to 7 of 7

Thread: old evap coil

  1. #1
    Join Date
    Sep 2011
    Location
    Western MA
    Posts
    2

    old evap coil

    I have an old McQuay evap coil with no numbers on it. It has two fans and the coil is 22"x44"x4" is there any to figure out the capicaty of this coil? Ant help would be great

  2. #2
    Join Date
    Oct 2009
    Location
    WI
    Posts
    114
    What is the evap for, cooler or freezer? Box size?

  3. #3
    Join Date
    Sep 2011
    Location
    Western MA
    Posts
    2
    its a cooler on a farm and it has been patched together. we just took over this account and the history i got is that they keep loosing compressors every 2-3 years. we just replaced the compressor and found txvs are way over sized. we want to install the correct valves but dont no what size the coils are. there are 2 coils in the cooler. the unit is running r22 which mekes think the valves were changed cause the coils are old

  4. #4
    Join Date
    Dec 2011
    Location
    USA
    Posts
    66
    If you suspect the TXV’s are over sized and you can not find out the BTU’s of the coil without doing a tube/fin calculation. You need to check the superheat and if you cannot throttle it down then put in a smaller TXV and check the superheat again.

  5. #5
    Join Date
    Oct 2011
    Location
    East Charlotte Area of NC
    Posts
    426
    Call McQuay, give them the dimensions, number of rows, fins per inch, etc, and refrigerant you are using and they should be able to tell you. They manufactured it after all.

    I can't fix it if it won't stay broke..

  6. #6
    Join Date
    May 2003
    Location
    Utah
    Posts
    732
    While not always a perfect indication of evaporator capacity, you can take the compressor model and find the performance chart for it...find its Btu capacity at the design condition. The evaporator capacity should be close (+/- a few %).

  7. #7
    Join Date
    Jul 2000
    Location
    Guayaquil EC
    Posts
    10,364
    My Dad had a rule of thumb for the capacity of low profile evaporator coils:
    • 1 Fan = 1/2 HP
    • 2 Fans = 1 HP
    • 3 Fans = 1.5 HP
    • 4 Fans = 2 HP

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event