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Can i use furnace sealant to replace a gas heater firebox sealant

matthew_rogers
matthew_rogers Member Posts: 33
edited January 2016 in Gas Heating
quick feedback wanted.
i just cleaned the burner tubes in my gas heater
i removed the back hatch and slightly weakened the back firewall calking while removing a stubborn screw.
(this firewall piece is abt 6"x8" and soft: resembling soft kaowool and the color of firebrick)

there was a white sealant applied to the top of this small pad
this sealant insured a tight seal between the top of the pad and the base of the metal radiator sections.
this white sealant was loose when i first noticed it, and fell off as i removed the back plate.

i have furnace sealant on hand (black) but i know its 2000 degree rated and hard curing.
i figured the hard sealant that has fallen off (white colored) was essentially the same material.

i am about to:
#1 put a bead of my black furnace sealant on the firewall pad to replicate the pre-existing white sealant.
#2 i will slide it up to meet the radiator and screw the back plate back on.
#3 I will let it air dry 1hr
#4 and then fire up the heater.

am i making a decent 1:1 fix? (temperature is dropping here in MA)

Comments

  • matthew_rogers
    matthew_rogers Member Posts: 33
    i went ahead with the sealant patch, a Plumber/Heating contractor looked at it, shrugged and said it was fine. I'd prefer a bit more chemistry in his shrug.

    does anyone know what sort of MSDS i could pull to identify the compound used to seal the seams in a forced hot water boiler?

    I will then compare it to the furnace sealant i used to seam my boiler.
  • Tim McElwain
    Tim McElwain Member Posts: 4,480
    Go to a plumbing and heating supply and bring what ever you used and ask them if it is acceptable for what you did. That is for your sake the simplest approach.
  • matthew_rogers
    matthew_rogers Member Posts: 33
    thanks, will do
  • matthew_rogers
    matthew_rogers Member Posts: 33
    only feedback i get from all plumbers and vendors is a shrug.

    firebox is tight now and sealant is hard.

    specs on the product i used did specify ratings for repairing fireboxes and the like.

    besides its just functioning as a tiny bit of air sealant (2000 degree caulking)
  • Tim McElwain
    Tim McElwain Member Posts: 4,480
    What is the exact information on what you used and I will look it up for you as to application. Need manufacturer name and perhaps a picture of the tube, can etc.
  • matthew_rogers
    matthew_rogers Member Posts: 33

    What is the exact information on what you used and I will look it up for you as to application. Need manufacturer name and perhaps a picture of the tube, can etc.

    product i used:
    rutland furnace cement
    upc: 022624000655
    product name: No65

    outer frame is nice and cool for last couple days since i introduced this product to replace the cracked/loose/missing material.
  • Tim McElwain
    Tim McElwain Member Posts: 4,480
    Furnace cement does not work well with high temps it will dry out and you will have the same problem. You need a refractory cement for what you did.