Atwood Furnace won't stay lit

[Klereue]

I recently bought a 2000 Dodge Coach House and the furnace blew hot air when I bought it a month ago. hadn't used it for a few weeks and now it just blows cold air. with the access panel open I turn on the Thermostat and the fan blows, then I hear a rapid ticking of the ignitor for a few seconds and the exhaust gets hot. Then the ticking stops and exhaust goes cold. the fan stays running and the ignitor retries 3 times, I'm assuming the ignitor is working because I hear it ticking, after the third try I can smell propane, so I'm assuming the gas valve is opening, but it just won't stay lit. It's an Atwood 8516-IV-DCLP if that helps.

The stove top burners burn strong, even when the furnace is attempting to lite, and the water heater works fine.

[nothermark]

Make sure there is no interlock sensor on the panel.

Could be something decided to winter over in the burner pipe. Might want to run a brush through it.

Might also want to find the manual on line to see if it has error codes or troubleshooting suggestions.

[Klereue]

I'll have to give that a shot, thank you!