Atwood 8835 - iv will not ignite - 9 year old furnace

Here's the good news - the furnace now works. I played around with the wiring which caused the furnace to 'kick in'. Following a 6 1/2 hr. drive to our present location and it's still working fine. Thanks to all to wrote in to help. BB

I don't know about the light. But, most furnace problems are because Wasps (or Mud Dauber Wasps ) have built a nest, or nest's, in the furnace outside vents.

If it can't get fresh air or get rid of the exhaust gases it will not light.

Use a flashlight to look down the intake and exhaust tubes and see if there is anything in there.

Even if you can't see it this could still be the problem. I once removed a furnace, shook it upside down, and dumped a whole coffee can full of wasps nest's out of the plenum.

When that light on the board turns from green to red, it is trying to ignite. This sounds like a gas flow problem.

Maybe the gap in the ignitor has changed. This happened to mine. I reset the gap and tightened the loose screw that caused it and no more problems. You can find the gap distance in your book or on line. Unfortunately I had to remove the furnace to get at the little bugger.