Furnace/AC problem

[FL SNIPER]

Not hunting or fishing related but wondering if anyone has ever came across this problem with their home Furnace/AC before:

My fan for my furnace and AC came on and will not turn off...regardless of whether it is in the "auto" or "on" position on my thermostat. And neither the AC nor the Heat will turn on. I turned the power off to the furnace in the hope of "resetting" something. But that did not help. It started yesterday...the thermostat was in the "off" position meaning neither the AC nor Heat was on...and the fan was in the "auto" setting...and then the fan came on and stayed on regardless of what setting I put the thermostat on. Anyone have this problem or similar problem before? What was the cure?

I am going to put in a new thermostat tonight to see if that fixes the problem. I did not have any trouble with either the fan, AC, nor heater before yesterday.

Thanks for any advice.

[SCUMFROG]

It might be on a timer if it's on auto. Runs for so long then shuts off off for so long. Before you replace any thing I'd try and find the book for your contoler and see if it is on a timer.

Also, does it have a fan off/on switch? I know it sounds dumb but you might not be looking for that but it's look right at you..

[FL SNIPER]

It's an old school thermostat, not programmable, not digitel, pretty simple with just a couple switches on it...so there are no timers on it. But maybe you are talking about something on the furnace itself as far as a fan "timer"??

Yes...there is a fan setting on the thermostat...either fan is "on" or "auto". I checked that out...but the fan still runs regardless of what setting I put it on and regardless of the temperature I set.

The main thing that concerns me is neither the AC nor the heat will turn on. It's like the AC and Furnace are not responding to any changes I make to the thermostat.

Thanks for the input...maybe that will help someone else in guessing what the problem is.

[lawdog]

I'd guess that either the thermostat is shot or you have bad switches in the furnace. Call a repair man.

[FL SNIPER]

I'll change the thermostat myself. Maybe I'll get lucky and that will be it. If that don't work I'll call a repair man.

Thanks for the advice.

[WalleyeWeasel]

Disconnect the wires for the t-stat (inside the furnace ) this should stop the fan, if the fan still runs, the contacts for the fan are sticking, if the fan stops and then starts back up when you hook the wires back up then it's the t-stat....good luck !!

[FL SNIPER]

I replaced the thermostat...that wasn't the problem because I still had the same symptoms afterwards.

So I called in a Pro. from Stacy, MN. Turns out it was some kind of "pull out" sensor (I may not have that totally correct) that was close to my pilot light. The pilot light was kind of dirty so it has been kicking out a bigger flame than it's supposed to...it set off the nearby senser and ruined it. So the Pro cleaned everything up and actually got the old senser working again until a new one arrives.

Over all I got by cheaper than I thought I would. Told me something though...a guy should clean out his furnace every now and then or have a Pro come out and do it to catch problems like I had. The Pro said that soot builds up on things and ruins them.

If anybody is looking for a good service repair guy in the north metro...let me know.