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how to replace a thermo couple on a

addadd Member Posts: 94
buderus model gc124 18/3 sp ,do  I need to pull out the entire burner assembly in cluding the gas valve?thanks in advance for any help.


  • 4Johnpipe4Johnpipe Member Posts: 479
    Boiler Service

    Yes the burner tray comes out. Its not difficult. Shut off electric and gas. Take out 4 allen screws on top of gas valve that connect the gas valve 90 to the hard pipe. Remove the burner tray screws and disconnect the moles connections. The entire unit slides out. Then remove the pilot assemble screws once its out and replace. You might as well remove the top panel of the boiler jacket and brush down the heat exchanger then vacuum the combustion chamber before sliding everything back in.
    Considerate People, Considerate Service, Consider It Done!
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  • addadd Member Posts: 94
    What brand thermo couple

    Should I use Honeywell or?... Thanks for your help I am an oil man,It is for a friend of a friend and could not find the manual ,I thought so but wasn't 100% sure.Thank you.
  • 4Johnpipe4Johnpipe Member Posts: 479

    Or basically any universal coupler will do...
    Considerate People, Considerate Service, Consider It Done!
    email: [email protected]
  • Tim McElwainTim McElwain Member Posts: 4,436
    edited March 2014
    Most of the time

    you can remove the front burner cover and disconnect the thermocouple at the gas valve and then get down and reach in an loosen the nut that holds the thermocouple in place and unscrew it and then pull it out and replace it.

    The question is why are you changing it, has it been tested by taking millivolt readings? See RESOURCES ABOVE THEN LIBRARY THEN TIM'S CLOSET FOR HOW TO DO THAT.

    As for replacement it depends on the pilot but a Honeywell Q 340 will usually cover most applications, they run as far as durability and performance right next to a Johnson (now Baso Gas Controls LLC) Husky. If you are having issues with frequent changes a Baso K16LRA corrosion resistant, high temperature thermocouple will take care of that.

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