I have a Intertherm Split System A Frame unit.
I turned the furnace on and it came on ran for about 1 min and went off. It did this 3 or 4 times then I turned if off. It was blowing heated air through vents, it just kept shutting off and comeing on every 1 min or so till I turned it off. Now it won't come on at all. There's two braker switchs down by the fan. There is no box or LED's with lights. Any help will do. Thank You. JazzyGG

The InterTherm website is useless, even if I had the model number.

Since the heat is starting, the high temp safety swithc may be defective or need adjustment. The unit may start after the switch cools down. If this occurs, should prove my diagnosis.

Try to find the high temp limit switch to determine if it is bad or can be adjusted.

I suppose the problem can be caused by a defective thermostat also.