Lennox Whisper Heat G20Q3/4E damper issue/not kicking on (1 Viewer)

[srcrosby]

I am in the market to get a new furnace installed, however in the meantime as I am collecting estimates, we have this lovely Lennox Whisper Heat g20, which, as I read more about is nearly a complete piece of trash. At any rate, the issue we are having is that, intermittently the heat wont kick on, the thermostat says "heat on" but no heat on. This is what happens, Ive watched it, the damper will open then immediately close, the igniter doesnt even try to light anything. Just damper open, damper close, and the only way to get the thing to kick on is resetting the power via the switch, this could take up to two to three tries before the damper opens and the gas is ignited. Ive cleaned the flame sensor as best I could as the two screws that are holding that flame sensor/igniter thingy in place are just frozen in there looks like someone tried to take them off before and mangled the heads of the screws. So I took a soft toothbrush and was able to reach this to try and clean it off a little, but I believe this issue to be pre-ignition. Any help will certainly be appreciated and many thank yous in advance.