suburban NT - 30sp problems

[JEBfs06]

I have a suburban NT 30 sp propane furnace. I have been having issues with it lately. It will come on, light supply heat for 2 to 10 minutes. It then shuts down and will not come back on unless I turn it off let it rest for thirty minutes restart and repeat. This evening I took the front panel off the furnace and ran it. I remained on, ran fine and cycled normally. I placed the panel cover back on and the problem started again. Any ideas as to what the problem may be?

[windrider]

Did you take the panel off the furnace, or did you just remove the grill off the wall for the air inlet? There is a difference. If you just pulled the grill off the wall, and it ran fine, sounds like the grill is to small, too small of an opening behind it, or something causing a restriction. Do you have anything in front of the grill like a trash can, clothes basket, etc,?

These furnaces must get a lot of air. Don't seem like they move much, but the intake can not be restricted. Sounds like you have a restricted intake causing an overheat, and the shut down. After it cools, it works again. Good Luck.

[JEBfs06]

I did not remove the fresh air intake panel I removed the actual metal cover panel from the interior. Once removed it runs fine. Which after what you've said makes a lot of sense. With the panel removed the furnace receives a lot more air and doesn't have a chance to over heat.

[JEBfs06]

And to clarify more I removed the metal panel on the front of the furnace not a an air register.

[windrider]

On the flip side. The furnace must not only receive air, but be able to get rid of it. Put the intake panel back on, and remove the the duct work and see if it runs. Could be some blocked ducts preventing air from getting out. Once again, are any of the ducts blocked by trash cans, clothes baskets, etc. ?