We have a intertherm furnace in our doublewide, house made in 2001 not sure model #. It will come on ignite and run, halfway through what should be a cycle the furnace kicks off but the preblower stays on. Then the furnace reignites again and runs until it gets to the desired tempurature. Then most of the time it shuts off. Any recommendations? Thanks!

The furnace may be overheating, activating the high-limit control. Check air filter, replace if clogged.