Luxaire Furnace wont fire

[murpracing]

I have an 11 year old Luxaire furnace.It is in a house I just purchased.It has not been run since november.I just put a new lp tank on.The furnace started and ran perfect.Once it got up to temp it shuts off.When it kicks back on it will start only the far left burner and once the blower kicks on it will fault out.It blinks red 7 times.I have tried starting it several more times and it will only fire the far left burner.So I even put a grill tank to see if that would do anything.It then fired up and ran good until it got up to temp and when it goes to fire back up it only fires far left burner and faults out.I hooked big tank back up and the same thing happened.Any ideas?Also I put on new chip board ,and gas regulator on the tank.I also cleaned the ignighter.

[ACtechGUY]

Your symptoms indicate a gas pressure problem . The only time I have ever seem what you are describing was when I had a very low incoming gas pressure.

[applianceman18007260692]

I had it happen on my furnace when I found out I had a stopped up drain pan. I got a toothbrush and cleaned the orifices real good and that fixed that.

[murpracing]

I had the service guy out and he cant even figure it out.He said that I am getting about 11.5 Inches is it of lp.I should let you know that the furnace ran the tank dry in November.I am starting in now since then.Also someone sugested that the lp lines might need to be blead off.Does that sound like a possibility?If so how would I do that.Thanks for the replies .

[RegUS_PatOff]

. . the furnace ran the tank dry in November

was the LP Tank disconnected for those few months ?

[murpracing]

No it was not disconnected just ran empty.

[ACtechGUY]

I suggest that there could be air in the tank and lines. If this is a permanent tank install , then break the union just before the heater and let the gas bleed out for a bit ( just don't light a match while doing this).

If it is a replaceable tank, then maybe the guy who filled it did not do a proper purge as it was filled. As a tank is being filled the bleed valve should be open. Otherwise AIR may be trapped in the tank with the LP gas.

[murpracing]

ok thanks will give it a try

[Bobice]

Sounds like a moisture problem. Especially since the tank ran dry.