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Stack temps for oil fired boilers

no lower than 275-300 and I insert the Tempoint at the chimney base to verify that.<BR>With a liner of course.<BR><BR>Dave


  • Jim P
    Jim P Member Posts: 29
    Stack temps for oil fired boilers

    With the new 3 pass design on some of the oil boilers that are out. What would be a good stack temp to prevent condensation in the chimney? With the 3 pass design, the flue gas temps are down to the 300-400 range. Low stack temps are good to a point (less money going up the chimney), but how low is too low.

  • Leo_15
    Leo_15 Member Posts: 20
    I read somewhere

    I read somewhere that a minimum of 335 gross stack temp to prevent condensation. Now A Viessman rep told me they get in the 235 range but you DEFINATELY need a SS chimney liner.

  • Robert Kushner
    Robert Kushner Member Posts: 5

    Below 250 degree F, you need reduce the chimney diameter with a Stainless Steel liner.
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