Lenox Gas Furnace - G10RD1-55-2

1. The fan contnous to run although the thermostat is set on extreme left/low.

a. Disconnected thermostat wire fan is still running.
b. replaced control relay but did no correct problem.

What else could be wrong. Pleas help.

 

Many furnaces shift the fan to full time if the high temp limit swtch opens. Any chance you could photo and post the wiring diagram?

 

Sounds like you are in a hot area? Probably the fan switch is being heated by the ambient temp inside the furnace. Do you have a.c. If yes turn on for a while and see if that cools the fan switch. I suspect you do not have a.c or it would have corrected by now.

 

Thanks I will send soonest.

 

Thanks...no A/C. Will continue troubleshooting later - heater is not yet needed this time it does not belong to me it belongs to a friend.

I was told there is a "fan-limit control" I did see that last time. I will look again.

 

Thanks I will ...they do not need the furnace yet.

 

I bet mbk3 is right. With one of those fan/limit control switches, you can have the stat turned down all the way, and not be using the furnace, and yet the furnace will have a mind of it's own and start up the blower if the temp in the house got too high. Why does it do that? Because the adjustable fan control "on" setting is set too low.

 

Thanks 'all. I am very thankful. I will locate the adjustable fan control and set accordingly first chance. I am fixing it for a friend. This is a good thing having found you - good guys..

 

I have located the control switch it is that black rectangular item located above the gas valve mounted on the furnace casing. There is a sliding knob, which was already at the extreme right. The setting range is 0 - 110 deg F. I operated the slide slightly to the left at 109 setting approximately. The fan stopped. However, it works intermettently. I suspect that, that part is worn out from normal wear and tear.

I need to replace it I think the part # is 1273-P3-1291. Cannot find it in at HVAC Part Warehouse's parts list. But will take the item out and bring to American Refrigeratrion Supply (ARS) they might have a replacement.

Can you tell me if I got the correct part number? Is there any link online that I can order it, just in case ARS cannot provide?

Thanks,

Nic

 

Does it say Cam-Stat or Honeywell on it?
Does it look anything like this?

http://www.a-1components.com/picture...8173000400.PDF

or this?

http://customer.honeywell.com/techli...0s/68-0024.pdf

 

Look more like Comstat but instead of a dial it has a slider under the numbers/setting. Otherwise everything is the same body and mounting. Thanks I think I know what to purchase. Thanks,

Nic

 

Making closure of this overdue thing. Brethren: The old fan control switch is not worn in fact it looks brand new. Operating the mechanism by hand stops the fan. I backed off the calibration screw 1/4" turn at the end of the thermal strips it worked. Closed the unit and tested several times, tested satisfactory. I have to return the new part. Thank you all.