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Need Confirmation of what This is...


I'm a little concerned about the exhaust pipe coming from the furnace going into the chimney - I need to know whether the compound that seals it is in fact Furnace Cement or if it's something else. It's flaking off, and needs some patch work. I'll upload some photos. I'm pretty sure that the stuff that's on the front of the boiler is furnace cement (a tech did that years ago bc the glass deteriorated), but not sure if the stuff that's on the chimney is or not. Seems like it's different stuff.... Can someone let me know? Thanks!


  • Steam
    Steam Member Posts: 45

    That looks to be the furnace cement you usually find in the plastic tub. Different makes can dry differently. Never cared for the stuff. If you want something better, chip that away and use castable refractory (mix it like cement). Once dried, and the expansion, contraction takes place on the flue pipe, you place a nice bead of 800 degree rutland sealent around it.

    Also, that field controls type M is not installed in the ideal location. It should be located on the flue pipe 12" minimum away from stack switch (installing toward chimney).
  • marcusjh
    marcusjh Member Posts: 79
  • Bob Harper
    Bob Harper Member Posts: 892
    Looks like you need a listed stainless steel liner and new smoke pipe with a tee, which is where the baro. damper goes.