Sorry for the snips and dip.

In respnose to THIS:

If my intention was to make someone else rich, I would have already
done so.
Thanks for your pointless advise.

In article , AC/DCdude17
wrote:

I've a gas furnace of unknown make, model and have an AC installed as
well.
I have useless advice, and not even the solution, so we're on a good
start already.

It connects to a thermostat through a four wire configuration.
The whole setup is about 13 years old.

Sounds old already, most AC units have thermostat wire running to the
equipment. We are still working on wireless stats.

The thermostat have three settings
like the average thermostat. A/C(Red, yellow and green shorted)

So you saying you have a dead short between R-Y-G
standard circuit for cooling? If it was short then it would be off,
hence "short".
,
heat(red, white and green shorted) and there's a switch labeled auto/on
that let's you turn on the blower manually(red and green shorted)
Heat---hmmmm R-W-G standard config for heat? Again with the
shorting..I hate short's, how bout you?

Every once in a while, furnace blower keeps running after turning off
after using fan only and only when I use fan only. I thought it was a
problem in the thermostat, so I pulled it out of the socket. Fan
continued to whir.

Oh yeah , thats what I would have done...


I measured the voltage across green and red and read 24V as the fan
continued to run, so it's clear that there isn't a short in control
wiring.
Yes, thats why it's usually printed on most 24VAC
transformers..uh....24VAC


To shut it off, I'll have to short red and green a few times with a
paperclip at the thermostat socket and fan eventually turns off.

Oh yeah, Thats would I would have done.....


If I don't do this, it contiues to run forever. I can also do the same
shorting technique to get the blower stuck running. My assumption is that
pulsating the control terminals turns it off by jiggling the stuck
terminals apart.

That the best diagnosis I have heard all week. Nothing Pulsates,
jiggles, or sticks, if you have well maintained equipment.
Someone answered you're question:

Noon-Air wrote:

You shou should also suspect that you will find a local, *competent*,
licensed, professionally trained, HVAC technician in your Yellow Pages.

If my intention was to make someone else rich, I would have already
done so.
Thanks for your pointless advise.

Is there anything I should suspect beside the mechanical relay?

No you need to call someone in the phone book under"A", for Air
Conditioning. Or what I should do is tell you what's wrong and let you
spend twice the amount of money at Radio Shack and Home Depot?

Have a nice Day?
Oval