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Why is the stack temperature so high?

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RayWohlfarth
RayWohlfarth Posts: 2,075
edited August 7 in Strictly Steam

I felt the heat from the flue while 5 feet away. After inserting my analyzer, the stack temperature read 600 degrees F. What causes high flue gas temperature?

Ray Wohlfarth
Boiler Lessons
GGrossMad Dog_2Alan (California Radiant) ForbesDrewM

Comments

  • EBEBRATT-Ed
    EBEBRATT-Ed Posts: 20,938

    Over firing, dirty boiler, inefficient burner with too much excess air, air leaks into boiler through leaking door gaskets, between section etc (if an old neg draft boiler)

    Mad Dog_2SlamDunkSiteReader
  • RayWohlfarth
    RayWohlfarth Posts: 2,075

    @EBEBRATT-Ed Yes sir I ran out of room Thanks

    Ray Wohlfarth
    Boiler Lessons
  • Alan (California Radiant) Forbes
    edited August 9

    Nicely done, Ray. I'd say the water-side scale issue is the most difficult to determine - and fix - but none of them are easy.

    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    MaxMercySteamfighter49
  • jumper
    jumper Posts: 2,605

    Only a theory. In the fifties HHW boilers were derived from solid fuel steam boilers. They sat on a firebox although they came with an oil burner. Later converted to gas. No engineering work.

    So heat transfer stunk. Only in seventies after energy crisis did anyone consider efficiency.

  • Fire_Man
    Fire_Man Posts: 1
    edited August 14

    Thanks for sharing this story. Draft requirements are often overlooked. When compounded by set-up errors and service/maintenance neglect; it is a wonder equipment holds up as long as it does. At the same time, life-span is dramatically shortened, heating costs are much higher than they should be, and unnecessary risk is created that will surely lead to costly repairs & replacement, or worse — a catastrophic fire.

  • RayWohlfarth
    RayWohlfarth Posts: 2,075

    @Alan (California Radiant) Forbes I agree. Scale is nearly impossible to access . They used to acid clean boilers but haven't seen that in a while.

    @Fire_Man Youre right draft is often overlooked when troubleshooting boilers.

    Ray Wohlfarth
    Boiler Lessons