Evcon LP flames die out

[comfortpro]

Evcon DGAT070BDC
This LP furnace fires up, flames look good for about 20 seconds then start to die down until the flame sensor kicks it out.
It has a WR 50E47-843 control.
any ideas on why the flame dies out slowly would be helpful.
Thank you.

[Robert]

Hi,

Do you have full 120vac to ignitor and does it stay energized for about 35 seconds or so ?


Clean sensor rod with steel wool and reset t-stat and run another cycle.


IF the gas valve maintained 24vac at connections and had correct manifold pressure, gas valve is ok.



Check burner and burner orifice for blockages.



Most common is sensor dirty/bad, bad ignitor and clogged orifice.




Thanks,
Robert