[rydholm11211]

HI , I have a Lennox G14 pulse furnace, and it will not start at all? I have replaced the Flame sensor and spark plug, and ignition control box? What else do you guys think it could be? im thinking maybe gas valve is bad or purge blower? When I turn on the furnace Should I hear the gas vale open? and should the purge blower be on as soon as you turn the furnace on? What I want to know is what should I hear down there when I turn on? And does this model have a main borad? I thought all it had was that black box, which I repalced? Any info would be apreciated? Thanks.

[rydholm11211]

Im thinking, and I think it is the relay that is bad, or the coil, But I am more leaning towards the relay, Im thinking that controls the gas valve.

[rydholm11211]

After reading up on How the Lennox pulse if suppose to work, I figured out that as soon as you turn on the temperature switch that, the purge blower on these should fire up immediately! Well I checkd the wires going to the purge blower, and they were reading at 122 volts, so it was getting power, but the blower was not working! so it has to be the purge blower is shot! So off to buy one of those.

[gabe_1981]

Sounds pretty safe to say that if you have power goin to the motor but its not coming on its time to replace ... Let us know how it turns out