furnace not working right

cwd

I have a Lennox Pulse in my house that is not switching on run heat. I can hear the pilot light on and it tries to ignite but never does. I looked at it and there is a green light on the Direct Ignite switch that is flashing. Does that indicate that is the problem? or does has anyone run into this scenario?

unclejohn

That is most likely the ignition fail code. Those furnaces where supposed to have a service preformed every 5 years. There is a service kit that replaces the " flapper " [every furnace should have one of those ] and some other stuff. Get that done by a Lennox dealer, others might not know about it.

Ironman

There's no pilot on that furnace.
How old is it? Eventually, the heat exchanger fails on all of them and Lennox has stopped offering most replacement parts, though some are available from after market sources.
There's a specific method of pressure testing the HX, but it's time consuming and usually not worth the cost considering all the other factors.
If your problem is anything more than the ignition module or igniter, you're probably better off looking at a replacement furnace.
That furnace is completely different than any other and you need someone who's trained and certified to work on it.

cwd

thanks for the info. I have a Lennox dealer scheduled to come look at it later, just had some questions.