Error code flashing on Lennox furnace

Head Scratcher · 03-25-2008, 05:47 PM

I have an error code flashing on the control box of my furnace.
The LED is light for 1 second and off for 5 or 6 seconds. Can anyone tell me what that means?

sgthvac · 03-25-2008, 06:46 PM

What is the model #?

Head Scratcher · 03-25-2008, 07:03 PM

Model of the furnace is G26Q3-50-2
Control Box Model is 63K2401

sgthvac · 03-25-2008, 07:15 PM

Head Scratcher,
I should have asked more questions. Have you turned power off and then back on? That will reset the control, watch the operation of the furnace. Does the inducer motor come on? Does the pilot light, does the main gas come on, do the burners light? Sorry for not asking these questions earlier, I'm home sick in bed.

Head Scratcher · 03-25-2008, 07:38 PM

I should have given more back ground.

Last week the furnace was shutting down due to condensation not draining away properly. I have a good slope on my drain now and this should no longer be an issue.

If I turn the power off and back on, the controller resets and goes through the normal cycle (purge for 15 seconds, then lights, or tries to light for 60 seconds). If it does not light I believe it is supposed to go in to retry mode which the controller says the LED will flash every second.

Rather then going in to retry mode the LED flashes as I said earlier, 1 second on and 5 or 6 seconds off.

sgthvac · 03-25-2008, 08:11 PM

Ok, well that helps some, When you re ran your drain, did you clean your trap(black box mounted on side of furnace)? Also remove the pilot and clean pilot oriface and flame sensor thats attached to the pilot with scotchbrite( has white wire attached to it). Let me know what happens.

Head Scratcher · 03-27-2008, 06:24 PM

Well I did as suggested, cleaned the flame sensor, and pilot. The trap, which I believe is between the blower and the heat exchanger is clear, I did not take it off of the furnace, but I can blow in the drain line with the condensation plug removed.

The furnace is working sometimes, almost half of the time it does not light itself when the blower turns on. then I get the same error message as before 5 off 1 on.