I am having a diagnostic "nightmare"... only due to lack of knowledge of the Lennox Pulse. This is a roughly '90 model. 80,000 BTU... The problem: Furnace lights for about 10 sec- 2 minutes... shuts down... It resembles a primary air problem, sounds of the fire sucking air. A previous tech just...

The furnace will run for about 30 sec, then shut down but the blower will stay running forever. It will try and light every minute after it shuts down. When it shuts down there is a red light that turns on for about 30 to 45 sec. Does this light tell me where to start looking for a repair?

My lennox pulse is not keeping my house warm enough, sounds like the fan runs constantly and can hear the furnace kick on for a few seconds at a time. What's the problem. BTW its -30* F this morning

We have a 15 yr old furnace. A Harmony II thermostat for zone control A Lennox digital thermostat for the upstairs,honeywell dial type for the down. We have disconnected the zone control as per our furnace installers directions. While the upstairs digital is set for 72 the furnace...

Could you Please guide me to a source to obtain the Schematic Diagram of Lennox G14 or G21 Pulse Gas Furnace? I could not find the company web site!