I've got a Fraser-Johnston model PACE-LD14N100A propane furnace. When I turn on the heat, the blower starts immediately instead of the usual ignition sequence. The igniter never heats, no propane goes to the burners - just the blower chugging away at circulating unheated air through the ductwork for as long as I leave it on.

Visual inspection of the igniter reveals no apparent damage. I've replaced the flame sensor, but to no effect.

I would be grateful for any advice!

Thanks!

Sounds like a limit problem. Check the limit switch operation first. Also could be the 50e 47 control board they tend to go bad often.

sounds like a limit problem. check the limit switch operation first. also could be the 50e 47 control board they tend to go bad often.

Thanks! I'll put an ohmmeter across the limit switches to check.