Announcement

Collapse
No announcement yet.

O.T. pilot light on oven goes out

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • O.T. pilot light on oven goes out

    Google just isn't do'in it.

    My Son In Law has one of those big ol country cast iron stoves, pretty old.
    He says you can light the pilot and all is good, but if you tell the oven to preheat
    to any temp it will reach that temperature and the heating gas will correctly turn
    off ... but ... so does the pilot. Obviously the pilot should not be turning off.

    I'm thinking its the gas regulator (assuming it has one)
    John Titor, when are you.

  • #2
    On modern stoves, a thermocouple is used to sense that the pilot light is properly lit.

    I can imagine a scenario where a thermocouple is overheating and faulting when the burner is on for an extended time. Thermocouples are often very cheap to replace, and sometimes are even easy to replace too!

    Dan
    At the end of the project, there is a profound difference between spare parts and left over parts.

    Location: SF East Bay.

    Comment


    • #3
      I have something similar happen where the pilot light/thermocouple is sorta iffy, where the pilot isn't good and so when the burner is on there is enough heat to keep the thermocouple happy but once the main burner shuts down then the pilot is too weak to keep the thermocouple activated and it shuts down (as it should).

      I would:
      Clean the pilot orifice or replace.
      clean the thermocouple/gas valve connection (I remove the end connected to the valve and rub on a clean shirt)
      I would suspect the thermocouple before a valve or regulator.
      If it a low pressure problem I would check or have it checked with a water manometer to be certain. Regulators are pretty durable.
      Last edited by Abner; 11-08-2017, 09:08 PM.

      Comment


      • #4
        Ok, he says he replaced the TC .. and...he said that over a year ago he replaced the regulator
        one time and it fixed it for a year .. but .. that now it is doing it again and he tried changing the
        regulator and it isn't fixing it this time.

        Add a weird clue. He says that to get at the TC .. he has to remove a panel above the burner.
        And that when he has that panel off, the thing works ok, but when you replace it, the pilot
        light does its bad thing.
        John Titor, when are you.

        Comment


        • #5
          Mostly, when the oven fire goes out, it does so with a pop.

          That can blow out the pilot, especially if there is supposed to be a shield on it, but it is not there, OR if the pilot orifice is clogged, which tends to happen.
          2730

          Keep eye on ball.
          Hashim Khan


          It's just a box of rain, I don't know who put it there.

          Comment


          • #6
            Exercise the junction where the thermocouple joins the control unit- maybe clean the thing while you have it out. Reliable low voltage (50 mv) operation requires solid connections.
            I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

            Comment


            • #7
              I guess i'll tell him to perform the magic ceremony of taking everything apart cleaning and
              reassembling .. just friggin amazing how many things that fixes.
              John Titor, when are you.

              Comment


              • #8
                On modern stoves, a thermocouple is used to sense that the pilot light is properly lit.
                Actually, on, ahem, Modern stoves, there is no pilot light, there is an igniter - I replaced one last week on our oven. They do die eventually, but are easy to diagnose and replace, if not especially cheap.
                "A machinist's (WHAP!) best friend (WHAP! WHAP!) is his hammer. (WHAP!)" - Fred Tanner, foreman, Lunenburg Foundry and Engineering machine shop, circa 1979

                Comment


                • #9
                  Low pressure gas is weird (or not) it doesn't take much to deflect it's flow like accumulated lint, spider webs, oven crud. Pilot orifices can be easily partially blocked.
                  You never mentioned what type of gas. Nat gas rises and propane sinks- would this add some extra hint to his open cover plate observation.
                  Make sure you use the correct pilot for the type of gas. Nat gas uses larger diameter with lower pressure and I found them to clog more easily.

                  I once had a heater where a small spider built a nest inside a main burner orifice. That can get a little dangerous as the gas can accumulate but depending on where the pilot is not ignite properly and BOOM. Always great to be watching when that happens and get your eye lashes melted together.
                  Last edited by Abner; 11-09-2017, 08:37 AM.

                  Comment


                  • #10
                    Mostly, when the oven fire goes out, it does so with a pop.

                    That can blow out the pilot, especially if there is supposed to be a shield on it, but it is not there, OR if the pilot orifice is clogged, which tends to happen.

                    i agree
                    had the same problem, soot and the vent was blocked by a cookie sheet

                    Comment


                    • #11
                      Inspect the pilot flame. It should be blue with minimum of yellow at the tip. The flame should be steady with the last 3/4" of the tc completely enveloped in the flame. Clean pilot orofice if needed. Are all guards in place? Check contact at gas valve for cleanliness and snugness, do not over tighten. You can measure millivolts, but it is much faster/easier to replace tc. If problem is not resolved a new gas valve may be required. Work flow is from least expensive to greater expense. Always helps to have manual for the unit with detailed instructions.

                      Comment

                      Working...
                      X