Check out some similar questions!

monkeypud · Nov 29, 2007, 09:26 PM

I have an Intertherm furnace with electronic ignition. When it kicks on it only burns for a couple of seconds. I have changed the module, gas valve, igniter,checked the exaust flue, and thermostat... Whats up, I'm stumped. monkeypud:confused: :confused:

hvac1000 · Nov 30, 2007, 04:11 AM

Does this unit have a draft inducer? You did not list a model number so how are we supposed to know what is in your furnace??

labman · Nov 30, 2007, 05:21 AM

Sounds like the flame sensor isn't working. You may be able to clean it. More details at https://www.askmehelpdesk.com/heatin...ons-58313.html

If you have a draft inducer, if it was the problem, the gas would never come
On.

hvac1000 · Nov 30, 2007, 05:50 AM

((If you have a draft inducer, if it was the problem, the gas would never come on.))

He has a Intertherm furnace. Many of these units use a end switch especially the ones used in Mobile homes. The end switch sticks even when the drafter inducer is not working (blowing) many times in the made position allowing the gas to flow but it will only flow for a very short time due to the high heat sensing disc. These units do not use a pressure switch as a safety only a end switch in the inducer. Since he did not say which model he has I could not look it up in my manuals. We need to get model numbers more often.

hvac1000 · Nov 30, 2007, 03:32 PM

Here is a parts diagram

http://www.qualityhtg.com/pdf/mg-mm_downflow.pdf

Your furnace does have a draft inducer. But does not have a Flame sensor.

Take the burner out and remove/clean the burner orifice of cobwebs or debris. If you rip the gasket you will need one of these (689009 burner gasket number 21 on the diagram),

This might be your cure and it is the cheapest first step to try and correct your problem. Report back with your findings.