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Block failure causes.

This is concerning a ten year oil fired old V-8 with a failed block. Boiler is connected to an indirect. Competitor tells customer it may be undersized which caused failure. I disagreed. I ran the serial number and found it was already replaced under warranty after 9 years. Burnham and I say block failure is due to undetected steam leaks in the system and/or water quality. No history of boiler flooding. Burnham says sizing wouldn't do it.
I measured the rads but have not yet added up the load as she was considering hvac instead.
What does anyone have to say about block failure caused by undersizing?


  • Jamie Hall
    Jamie Hall Member Posts: 22,947
    Block failure caused by underusing? That's a new one. Nice try -- but no cigar.

    How much water has been being added? That could do it. (steam leaks) So could firing it with not enough water in it. So could aggressive water -- such as very hard, or high chlorides, or ion exchange softened water.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    STEAM DOCTORethicalpaul
  • andprogeny
    andprogeny Member Posts: 5
    Under sizing. That's what a competitor told her and she seems to want to believe it. I've encountered things like this before and I just put tech support on speaker and let the customer hear everything.
  • The Steam Whisperer
    The Steam Whisperer Member Posts: 1,214
    Actually undersizing may make the boiler last longer.... nice long steady heating cycles reduces the expansion and contraction cycles of the boiler, reducing stress. A 1 year block life tells me there is something probably wrong.
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • andprogeny
    andprogeny Member Posts: 5
    10 year. First one was 9. This one 10. Still too short.
    I just spoke to her again. Going to replace the boiler after pressure testing the system,all new vents and valves where needed.
  • Steamhead
    Steamhead Member Posts: 16,734
    If you're not going to switch her to gas, the Burnham MegaSteam is the way to go.

    Good that the heat-pump pushers didn't get her.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    EBEBRATT-Ed Member Posts: 15,345

    and consider that even if it was undersized for how much of the year?? We only get to design temps a very small portion of the year
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,491
    I would look at chlorides in the water as the culprit. That's common with this boiler.
    Retired and loving it.