it heated up and ran a while then stopped. now it starts then stops within a minute
Can you restart it right away or do you have to wait a while for it to restart.
If you have to wait then often this is a motor problem.
The motor could be overheating and tripping it’s internal thermal cut-out.
It then has to cool down so the cut-out resets before it will start again.
I had this problem and fixed it by replacing the gas coils. There are two, a primary and secondary. The primary starts the gas flow, and allows the secondary to take over. If the secondary coil fails, the system shuts down. I replaced them both for about $20.00. Hope this helps.