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replacing condensing gas heat exchanger

zepfan Member Posts: 315
does anyone know if the secondary heat exchanger on a carrier model #58sxc furnace can be replaced without removing the primary heat exchanger? I have a family member that has one that  is leaking, and I have ordered the replacement heat exchanger, which unfortunately came with a lifetime warranty, and am planning on replacing both even though through testing it only appears that the secondary is cracked. I have never replaced one of this model before, and am just going by an exploded view of the unit. i tried to convince them to replace the furnace, they would get a better warranty, and all new parts, but they chose to replace the faulty part. any input would be appreciated. thanks to all. 


  • Pughie1
    Pughie1 Member Posts: 130

    No more recall heat exchanger claims for 58SX furnaces. The last date of the

    seriel numbers 28th week of 1993 & 20 years from installation. So although the heat exchanger itself might be covered, there will be no labor reimburstment. I,m quite sure the SXC's production ended in 1993.

    The secondary slides right out without removal of the primary. We did so many of these that we could easily do it in an hour.

    Are you sure a 20 year old furnace is worth this?

                  John Pughe
  • zepfan
    zepfan Member Posts: 315

    the only reason I replaced the heat exchanger was because it was under a lifetime  warranty, and it was for a family member that is trying to sell their house. I am aware that the labor credit  tops out at twenty years, and this furnace is well beyond that. replacing the secondary heat exchanger was a piece of cake, and I found out that it can be slide out without messing with the primary, however I would suggest to anyone that has to do this, if there is any doubt about the primary cells to go ahead and replace them, which I did because they are also under a lifetime warranty. thanks again
  • VictoriaEnergy
    VictoriaEnergy Member Posts: 126


    How do you fasten the primary/seccondary transfer box at the back of the furnace with out removing the whole assembly from the furnace?
    Home Owners Please Note:

    You are receiving advice from some very skilled pros completely free of charge. One of the reasons I participate is to sharpen my own troubleshooting skills. So; did we get it right? I would be grateful if you extend this courtesy back by posting the final outcome of the issue you are inquiring about. Thanks
  • Pughie1
    Pughie1 Member Posts: 130

    VA  -  On the SX through the SXC its all done from the front. The only tricky part is removing the "coupling" -  piece of metal between the primary & secondary. Gently using a couple of small pry usually would do it, then the secondary practically slides right out. We did so many of these the guys could do it in an hour.

    Different story on the MX series - they were "coupled" in  the rear.

                                                        John Pughe
  • Pughie1
    Pughie1 Member Posts: 130

    Sorry I failed to proof read.  I ment to say "small pry bars

  • furstanten
    furstanten Member Posts: 1
    The secondary HX on my 22 yr. old 58sxc has failed. It's covered under warranty but labor is not. Dealer proposes replacing both primary and secondary because they anticipate damage to the cell frame when removing the secondary. Comments here indicate the secondary will slide out without any effect on the primary. Is there a trick to sliding it out? Are there complications because of the age of the unit?
  • GlenP
    GlenP Member Posts: 2
    I have to replace my secondary heat exchanger on my 58SXC . I want to by one on line, does any one no a dealer that will sell to me I am not a hvac Contractor how ever I am a electrical contractor. I live in Ontario Canada
    regards GLENP.
  • GlenP
    GlenP Member Posts: 2
    Sorry I wanted to say I want to purchase one on line, and does any one know a online dealer.
    I better learn to proof read.
  • Henry
    Henry Member Posts: 988
    Glen, in Canada you as an unlicensed gas fitter or technician is not allowed to do anything on a gas furnace. Specialy in Ontario, if something goes bad, you can be held on criminal charges, prosecuted by TSSA etc...