5 year old, Bryant 94%, model 355AAV042080, on propane.
Bryant tech was out last November to clean burner orifices, adjust propane pressure - seemed to be OK.
Yesterday I got the ignition lockout code (means it didn't light properly). The burner (1 of 4) which flames on the ignition sensor was burning yellow, and the flame sensor was sooty.
Today I cleaned the flame sensor, and the burner orifice (the other 3 were clean). Forced it to run on propane (not the heat pump) and watched several ignition cycles. The ignition sequence seems OK - induction fan starts, ignitor glows, valve opens, and the burners catch on.
However, the burning startup doesn't seem "smooth". It used to light at the ignitor, then travel across the 4 burners in order. Now it sorta lights all at once - a "POOF". Often some of the burners will flame back to the orifice in the manifold - and burn about 1/2 yellow. If I blow it out (with my mouth) it'll relight at the burner orifice and burn nice and blue.
When its burning, I can feel the exhaust flow outside at the vent, but I'm not experienced enough to know if its as strong as it should be.
Sure would appreciate an experienced furnace tech tell me what's gone wrong - or what I need to check further.
Bryant tech was out last November to clean burner orifices, adjust propane pressure - seemed to be OK.
Yesterday I got the ignition lockout code (means it didn't light properly). The burner (1 of 4) which flames on the ignition sensor was burning yellow, and the flame sensor was sooty.
Today I cleaned the flame sensor, and the burner orifice (the other 3 were clean). Forced it to run on propane (not the heat pump) and watched several ignition cycles. The ignition sequence seems OK - induction fan starts, ignitor glows, valve opens, and the burners catch on.
However, the burning startup doesn't seem "smooth". It used to light at the ignitor, then travel across the 4 burners in order. Now it sorta lights all at once - a "POOF". Often some of the burners will flame back to the orifice in the manifold - and burn about 1/2 yellow. If I blow it out (with my mouth) it'll relight at the burner orifice and burn nice and blue.
When its burning, I can feel the exhaust flow outside at the vent, but I'm not experienced enough to know if its as strong as it should be.
Sure would appreciate an experienced furnace tech tell me what's gone wrong - or what I need to check further.