I had this problem. A heat sensor/thermostat had blown form over heating. It worked for a while. Now it went out again. I think the exhaust duct is full of lint causing the overheating problem.

If you choose to repair, clean the duct work too. The sensor swap is a band aid.

Do you know the capacity of this unit? I want to replace mine. Larger capacity is a higher cost. I want to mathc the current size of my unit.

Thanks