Hiya - My furnace is a Lennox GCS16 series. The furnace worked fine last season, but now the fan is not coming on. It is an outdoor unit and Im just wondering if there is anything I can do to try and correct the problem before calling a technician. Last week I tried turning off the unit for 30 minutes at the thermostat and this seemed to make it work again but only for a short while. Now when I turn it on I just hear a whirring noise but no fan coming on. The fan works fine when I put it in the on position at the thermostat but nothing in auto. ???
It sounds like the exhaust motor is running but no ignition. It could be a dirty flame rod, bad ignition module or worn electrode. You will probably need service.
Thanks Admin : I think you may be right. After shutting everything off and restarting, it worked for a few minutes including flame but then nothing on a second attempt (no flame on 2nd try). I just dont know where to start so calling a tech ;)
That sounds like flame failure. That will be an inexpensive service call. You shouldn't need any parts, just a cleaning.
Ok tech has been here - he replaced the DSI Control (175$) suggesting some of the circuitry was failing. He also checked the Flame Rod and found it to be fine. Furnace is now responding normally. I will update this thread if anything goes wrong over the heating season. Thanks all.