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Mandoguy's avatar
Mandoguy
Explorer
Apr 04, 2018

Porcelain points

I just got my BT Cruiser back from 4 seasons rv where they got the furnace working. I've read and watched a lot of stuff about Suburban furnaces but never heard of what they diagnosed which was " cracked porcelain points" in or on the burner. The service guy couldn't really describe them. Anyone know what they're talking about?
Class B
  • donn0128's avatar
    donn0128
    Explorer II
    Apr 04, 2018
    The only thing porceline I can think of on a gas furnace is the igniter.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Apr 04, 2018
    The 'Spark Electrode' has a ceramic insulator that the High Voltage wire runs thru to connect with electrode.
    Transformer on circuit board sends 2000+ Volts thru that electrode for spark

    BUT more importantly that electrode is used as return for milliamp flame proving signal that circuit board must receive or it shuts down firing

    Cracked ceramic insulator will 'leak' that milliamp signal to ground and not return it to circuit board.

    Example of a Spark Electrode.....white portion is the ceramic insulator





    'Service Guy'.......hopefully that was just the counter person and NOT the actual tech :S

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