My Trane furnace is having issues staying lit. The control board light gives me an error of 2 flashes, which doesn't tell much. The heating element seems to be fine, and the gas valve opens and I can see flames. But, after 2-3 seconds, it shuts off the gas valve again, and when it does I hear a small "whoosh" or "hiss" sound. After cycling through, it will try again a couple times until I get the error code.
I cleaned the flame sensor last night, and it did start working after a couple tries, but only stayed on for 20-30 minutes before shutting off again.
Other than trying to clean the flame sensor again more thoroughly today, what else can I try? I spoke to an HVAC tech who told me I might be having an issue with my control board, or might need a new "capacitor" which is common with Trane furnaces. After doing some research I'm thinking he meant a Run Capacitor.
Please help if you think you can.