# help on a gas furnace ignition problem



## zorroo (Nov 19, 2008)

Our gas furnace stopped working.  The problem is when the thermostat calls for heat, everything looks normal from beginning: the induction fan starts to spin, then the Hot surface ignition comes on.  The problem is now there is no flame comes on.  It looks to me the gas valve does not open at all.  The ignitor comes on for three times and stops trying.  I did not see any broken wire.  

I don't have much experience here, so any suggestion is helpful.  Thank you!


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## glennjanie (Nov 19, 2008)

Welcome Zorroo:
There may be an air velocity switch that will not allow the gas to come on until there is sufficient ventilation. I would check for obstructions in the vent pipe, look at the vent cap and see if it is in good shape.
Glenn


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## zorroo (Nov 19, 2008)

Thanks Glenn, did you mean the fume pipe to the roof?  




glennjanie said:


> Welcome Zorroo:
> There may be an air velocity switch that will not allow the gas to come on until there is sufficient ventilation. I would check for obstructions in the vent pipe, look at the vent cap and see if it is in good shape.
> Glenn


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## glennjanie (Nov 19, 2008)

Yes, that's it.
Glenn


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## zorroo (Nov 19, 2008)

Thanks Glenn, I will have a check next week when I when to the house.  I will come back to report my findings.


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