Hey folks, I'm new to the forum. Told a buddy i had a problem and he said to come here. I'm working on a Lp Trane GRAA 350000 btu rooftop. Got a call after the propane tank was refilled because the unit failed to light. Purged the gas train and still got nothing. Checked for spark and had a bright one. The gas valve manometer port was striped so I changed it out (Honeywell single stage standard opening). Changed pilot assembly while I was at it just in case. Gas pressure was 10.8 in. Only thing I can think of is bad mix but I've tried a range of pressures. Does anyone have any ideas?