What could cause a water heater's pilot light to go out?

Discussion in 'Off Topic' started by FightingChance, Apr 22, 2009.

  1. FightingChance

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    Old apartment but very new water heater (gas). The pilot light keeps going out... we have to re-light it in the morning about 3-4 times a week. Re-lights easily by following instructions. Stays lit the rest of the day (usually.) No water leaking.

    Mysterious. Thoughts?
     
  2. spidey07

    spidey07 No Lifer

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    Gas pressure? Sometimes you can adjust the level of the pilot light.
     
  3. tw1164

    tw1164 Diamond Member

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    Serial Killers
     
  4. FightingChance

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    There is a three position knob on the front of the heater, with 'ON', 'light' and 'OFF'. The only other adjustment knob is the heat of the water.

    Or perhaps you mean the actual spigot that allows gas flow into the heater at all? Could it simply be set too far open? (or closed?)
     
  5. Rubycon

    Rubycon Madame President

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    Downdrafts

    The thermocouple may be going bad or not aligned. It needs to be touching the flame at all times. If it cools it will stop producing EMF which will cause the valve to close shutting off the gas.
     
  6. skull

    skull Senior member

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    Could be a bad thermocouple. I'm guessing since its new its the type thats behind a glass window. So your probably not getting a draft blowing it out. Does the flame look strong?
     
  7. illusion88

    illusion88 Lifer

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    make sure you dont blow your house up the next time you relight it.
     
  8. FightingChance

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    It is the kind behind a little glass window, so I can see the pilot itself. I don't think any kind of draft is getting in there, we experiment by opening and closing the back door (which is right next to the closet the heater is kept in) rapidly but nothing happened. The flame seems fine, but I'll take another look.
     
  9. iGas

    iGas Diamond Member

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    1. Draft, try putting the ignition chamber shield back onto the heater tank, or bent/place a shield in front the pilot light.

    2. Make sure that the pilot flame is at the top 1/3 of thermocouple (reposition if necessary).

    3. Clean thermocouple with emery cloth/sand paper if it is full of soot.

    4. Make sure thermocouple is screw on tight to the gas valve assembly.

    5. Replace thermocouple if it produce less than 10 milli amps.

    6. Replace gas valve assembly if it is malfunctioned.
     
  10. iGas

    iGas Diamond Member

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    OFF = all gas valves are shut off in the gas valve assembly.

    Light = gas valve to the main burner is off, but pilot valve is on (depress pilot button and light in this position, hold button down for up to 2 minutes to let thermocouple reach operation temperature).

    ON = gas valve to the main burner is on, and safety valve is on/off pending the control of pilot light & temperature bulb/bimetal valve.
     
  11. skull

    skull Senior member

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    It sounds like its the thermocouple then. Its the metal thing the flame should be hitting. If its in the flame its probably just bad and needs to be replaced. There cheap and easy to change you can get them at any hardware store.
     
  12. FightingChance

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    There is a little shield in front of the pilot light chamber. The pilot light likes to go out no matter if it's been in place or not.

    I'm not quite sure how to access that chamber; it seems to just be an area at the bottom of the heater. I assume there's just something you can remove to get to it, though as it's an apartment and is not my heater, that's starting to get beyond my responsibility. However, this is one of those things that it's painfully difficult to get a landlord to call a plumber or similar and then have them come out and have to stay home from work while they twist a knob or two, so I am very much about fixing this myself - if I can.

    I hate to ask, but what exactly is the 'thermocouple'?
     
  13. FightingChance

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    I'm 99% sure that the little pilot flame does touch a disc-like element, which I assume is the thermocouple. Hmm.

    Thanks all for your replies so far, very helpful in tracking this down.
     
  14. iGas

    iGas Diamond Member

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    The disc-like element is the main burner spreader disk.

    thermocouple look like a probe.

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  15. skull

    skull Senior member

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    The thermocouple will be connected to the gas valve with a copper wire.