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Gas Pressure Drop?

WayneB Member Posts: 1
<span>The problem that I am having with my home hot water boiler is as follows</span><ul><li><span>The boiler will not prove and light the main burners</span> </li><li><span>This only occurs during the coldest days</span> </li><li><span>There are no drafts by the boiler other than the induced draft flue</span> </li><li><span>When the problem occurs, there is no regard to other gas appliances operating within the house</span> - all are off</li><li><span>The pilot light is lit and the system is attempting to prove.</span> </li><li><span>The system has a mercury flame sensor</span> </li><li><span>The issue has been determined to be that during the times the issue occurs, the pilot light is not encompassing the flame sensor bulb.</span> </li><li><span>This has been verified by applying a propane torch flame to the bulb which then allows the main burner to ignite and the system heats to max temperature before the main burner is turned off and the issue reoccurs.</span></li><li><span>It is not the flame sensor because I have a spare one from trouble a number of years ago, and I swapped out the flame sensor with a new spare.</span> </li><li><span>The pilot flame has been adjusted as far as I believe it could be.</span> </li><li><span>Once the outside temperature increases – the boiler is able to light on it's own.</span> </li><li><span>The problem sometimes occurs at night when it’s cold and by morning the system is working just fine again.</span> </li><li><span> </span>

<span>Does this sound like a pressure drop at my main line when all my neighbors heating systems are running?</span>

<span>What do you think?</span>

<span>How can this be corrected?</span></li></ul>


  • Tim McElwain
    Tim McElwain Member Posts: 4,482
    First try cleaning

    the pilot, mercury pilots have to get the tip of the mercury sensor to glow cherry red otherwise the mercury will not boil. Sometimes simply taking the pilot apart and cleaning the pilot orifice will solve the problem.

    Have a professional with a manometer check the gas pressure when this is occurring

    Does this system have a little white pilot relight box numbered 5059?

    Is this a White Rodgers cycle pilot system with a 36C84 gas valve with a built in pressure switch?
This discussion has been closed.