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Furnace Hi-Limit Safety

Reading the very sad news Dan has on the site about the deaths caused from overheating.

I wonder if there is a Hi-limit temperature setting on the furnace, in case the thermostats malfunctions and stays closed??

Comments

  • Tim McElwain
    Tim McElwain Member Posts: 4,612
    All furnaces have

    a high limit usually set at 200° (F) to open and shut down the burners.



    A lot of the new furnaces have "Self Healing" feature which means the fan and also sometimes the combustion air blower will come on any time a limit opens.
  • Devan
    Devan Member Posts: 138
    edited October 2009
    Right

    so how can two perish from an overheating in a room, suspect, malfunctioning furnace.

    Not CO, overheating?
  • Tim McElwain
    Tim McElwain Member Posts: 4,612
    I would ask Dan

    as I am not familar with his article. Where did it appear?
  • Devan
    Devan Member Posts: 138
    News Article

    Here you go, I should have posted it before:



    http://www.heatinghelp.com/news/article/59/Twins-die-when-heating-system-malfunctions
  • Tim McElwain
    Tim McElwain Member Posts: 4,612
    It doesn't state

    what kind of system it was. I have seen electric heating systems do this but typically not something gas or oil would do that. It could happen if the gas valve stuck open but very unusual especially with dual seated gas valves used today.
  • Devan
    Devan Member Posts: 138
    edited October 2009
    True

    but I did make the assumption since the article states there were two seperate units, one on the lower level, and one on the upper level wheret he boys slept.Doubt it was two boilers, in Georgia,
  • Tim McElwain
    Tim McElwain Member Posts: 4,612
    You are correct

    it is probably a warm air furnace, heat pump etc type system.



    Bottom line always check to make sure systems shut off on the safeties.
  • Devan
    Devan Member Posts: 138
    Good point

    As part of annual check up, check to make sure system shuts off.
This discussion has been closed.