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Ignitor fires early or gas valve turns on too late - no ignition

Here is the sequence I see.

I ask for heat. The combustion exhaust fan comes on. The ignighter glows. As the glow fades, I hear the gas valve clicking open but as if it is too late, it turns off, never firing the burners. I smell a hint of propane at this point.

However, if when I hear the valve kick on I BLOW THE GAS THROUGH, THE BURNERS IGNITE! - and the system stays on until the demand for heat is satisfied. But, next time, If I am not there to blow on it, the system attampts to light 3 x and on the last fail, the house blower fan comes on. I can only turn it off by cutting current to the unit. This also re-sets the unit to go through another 3 cycle attempt to fire.

It is as if the igniter and the gas valve are no longer in synck.

The error code is 2 flashes - system lockout (no flame) check line polarity.

Again, if I blow the gas to the fading glow of the igniter, the unit fires and continues to work just fine so I guess all the limiters and safery circuits are functional

The unit worked fine for years. Then a few times, we just turned the power off and it fired the next time. Now it seems the delay got worse.

Is there a way to re-set the cirquit board? any suggestions or revelations on what is wrong? Any questions to clarify my problem? Please ask. I have a multi-tester and can read wiring diagrams and usually manage to fix things myself. This time I need help. Thank you in advance for providing it.

Roadskiman

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  • roadskiman Nov 24, 2008

    The burners were a litle rusty and so the gas did nopt travel well into the ignighter and flame did not light. I took each burner off, cleaned the fins, re-installed and all worked fine.

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Put your hand on the gas valve and see if the click of the valve is opening just before the ignitor goes off if it does your valve is going bad

Posted on Nov 13, 2008

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The unit cycles through all levels and then displays Ignition failure, code B2. I replaced the flame sensor, the ignitor, and there is natural gas at the gas valve.


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Won't srtart


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Hope this helps

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