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condensing furnace in attic

Paul S_3Paul S_3 Posts: 1,257Member
I have a few customers with 90 plus condensing furnaces in unconditioned attic spaces....a few of them have had problems with freeze ups the past 2 winters....question is it against any mechanical and /or fuel gas code to install these units in NYC?... thanks Paul myself wouldn't install these in a unconditioned attic for these obvious problems. Just want to have something definitive.
ASM Mechanical Company
Located in Staten Island NY
Servicing all 5 boroughs of NYC.
[email protected]


  • lchmblchmb Posts: 2,953Member
    install manual say's they cannot be installed in unconditioned space...That makes it against code...
  • Paul S_3Paul S_3 Posts: 1,257Member
    Thanks for response
    ASM Mechanical Company
    Located in Staten Island NY
    Servicing all 5 boroughs of NYC.
    [email protected]
  • Steve MinnichSteve Minnich Posts: 2,474Member
    In my neck of the woods (Chicago), in order to make a condensing furnace installation legit in an attic you have to build an insulated room around it, and provide heat to that room from an independent source.
    PHC News Columnist
    Minnich Hydronic Consulting & Design
  • unclejohnunclejohn Posts: 1,420Member
    I would not install condensing furnace in attic but from the Lennox installation manual...• When the furnace is installed in an unconditioned
    space, consider provisions required to prevent freezing
    of condensate drain system.

    Failure to protect against the risk of freezing may result in
    property damage.
    Special precautions MUST be made if installing furnace in an
    area which may drop below freezing. This can cause improper
    operation or damage to equipment. If furnace environment
    has the potential of freezing, the drain trap and drain line must
    be protected. The use of accessory drain trap heaters, electric
    heat tape and/or RV antifreeze is recommended for these
  • Empire_2Empire_2 Posts: 2,343Member
    No problems here from all of the above. No! Not only that but voids ANY MFG. warranty.
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