Air Conditioning - fan won't turn off

My fan in the heater will not turn off. My AC unit goes on and off per the thermostat setting. So does the heater. However, if I set my thermostat to 70 and it reaches 70, the AC unit outside will off, but the blower in the Lennox heater will keep on blowing. If I set my heater to 70 and it reaches 70, the flames will go out, but the fan will keep blowing.

Any suggestions? I think I just wasted 50 bucks on a heater/cooler thermostat (doubt if I can return it), and I still have the same problem.

Thanks.

Did I see new tstat???? Is it wired right???? Pull G wire off tstat and see if blower stops.If not hit side of furnace real hard with your hand. If stops you need new fan relay in unit. Post back in same post here.

ED ;)

I installed the thermostat wires the same as they were on the old.

I removed the G wire...fan did not stop. What does the fan relay look like? Where do I find it?

Thanks,
Dan

Some of the relays are attached to a junction box where the power comes into the furnace, some are located in the blower compartment attached to the blower housing.
Let us know if you have anymore questions.

HiltonTech

I popped the sheet metal cover box off the furnace. There is a wiring diagram on back. It lists a blower relay, combustion air relay, heat blower relay, economizer heat relay, continuous blower relay and an accessor relay. Which one is it? If I know which one it is, I can order it and when it comes in, I'll know how it looks like and just replace the similar part.

I hit the box, but the fan kept on going. I don't see any shorts, so I think it probaly is the relay as you say it is.

continuous blower relay

This is the one Id start with here. On some you have to get the whole board for it. Dont know here on yours


ED ;)

Thanks for all your help guys!

I switched out the whole circuit board ($140), the one (and only one) with the fan relays on it and it works!