(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 4 of 4

Thread: Residential Evaporator Coils Placement

Hybrid View

  1. #1
    DIY Member grahamW's Avatar
    Join Date
    Jan 2012
    Ontario, Canada

    Default Residential Evaporator Coils Placement

    A quick question regarding the placement of the evaporator coils placement on top of a residential furnace. Within the plenum above the furnace, is there supposed to be a gap between the coil and the top of the furnace? If so, how much of a gap and what supports the condensate tray. Mine currently rests directly on the top of the furnace whereas my previous home had it located further up the plenum.


  2. #2
    DIY Junior Member Big Chicken's Avatar
    Join Date
    May 2012


    I think this depends on the brand you have and how it was installed. I've seen some ingenious installations before in a plenum that involved custom work. I've also seen some scary setups that resulted in condensate running back into the furnace instead of out the condensate hose. Some brands use a coil box that screws right to the furnace itself, leaving very little gap between the coil and the furnace. Condensate trays can vary as well based on the shape of the coil.

  3. #3
    Plumber jimbo's Avatar
    Join Date
    Aug 2004
    San Diego


    Unless your coil is matched to the furnace...unlikely that a new coil will be a match to the old furnace....then some creative sheet metal will be required. No problem.

  4. #4
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    New England


    One thing often specified, and probably as often omitted, is a decoupling section of plenum or ductwork between the working hardware and the rest of the ductwork. This is often a short plastic coated canvas section. It is quite important to prevent vibrational noises from the HVAC plant into the rest of the ductwork. Drain pans sometimes have a redundent, overflow pan - you really don't want that condensate draining through your furnace! On my air handler, it's designed as an upflow, and it's below the working parts, but most furnaces are designed with it after, or above.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

Similar Threads

  1. 3.5 ton evaporator
    By mp6199 in forum HVAC Heating & Cooling
    Replies: 1
    Last Post: 01-01-2011, 10:19 AM
  2. Clogged AC Evaporator line
    By vaman in forum HVAC Heating & Cooling
    Replies: 3
    Last Post: 11-10-2009, 08:21 PM
  3. How cold should Evaporator Coil Unit feel?
    By dscogin in forum HVAC Heating & Cooling
    Replies: 3
    Last Post: 09-11-2009, 05:53 PM
  4. Should I try to clean the A/C coils myself?
    By riker1384 in forum HVAC Heating & Cooling
    Replies: 6
    Last Post: 11-11-2008, 05:44 AM
  5. What is with the hot water coils?????
    By Larry4 in forum HVAC Heating & Cooling
    Replies: 2
    Last Post: 12-12-2007, 07:10 AM


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts