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Furnace or Thermostat issue?

Hi Everyone,

I recently replaced my thermostat and upgraded from a mercury based thermostat to an electric programmable model and am having some issues with my furnace. Let me know what you think:

When I turn the furnace blower on "auto" and the heat to on and set a temp above the room temperature, the heat turns on, the fan turns on, and the house is brought up to temp. The furnace kicks off and the fan keeps running. When I turn the thermostat to "off" from "heat", the fan still runs. The only way to get the fan off (ironically) is to turn the fan setting to "on" from "Auto" and the system shuts down.

When I installed the new thermostat, I don't think I diagrammed the old wires (stupid, I know) but could incorrect wiring be causing this problem? If not, do you think this is a fan/limit control issue? This is an older furnace (an Imperial II from GE, at least 15 years old MODEL NUMBER

21LU130K28) and the thermostat is a honeywell RTH111/221.

Any advice here would be appreciated.

Sincerely,

------------------------------------- James Kirkby

Reply to
JKirkby
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Captain Kirk,

how many wires were hooked up to the old mercury thermostat? was it one of those YoYo types? prepare to be treated here.

Reply to
Real Pisser

Hi There - thanks for the warning :)

There were four wires with the old thermostat. After disconnecting them and realizing that I should have paid attention (duh), I used the old thermostat to map the new connections as best I could as some of the old wires were still leading to the connections.

The old thermostat was rectangular and used mercury to tell the temp and had the same setting as the honeywell. It was just old as dirt and not programmable.

------------------------------------- James Kirkby

Reply to
JKirkby

JKirkby had written this in response to

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:

Captain Kirk,

how many wires were hooked up to the old mercury thermostat? was it one of those YoYo types? prepare to be treated here.

Hi There - thanks for the warning :)

There were four wires with the old thermostat. After disconnecting them and realizing that I should have paid attention (duh), I used the old thermostat to map the new connections as best I could as some of the old wires were still leading to the connections.

The old thermostat was rectangular and used mercury to tell the temp and had the same setting as the honeywell. It was just old as dirt and not programmable.

------------------------------------- James Kirkby

Reply to
JKirkby

I don't suppose that you actually *READ* the operating manual??? nope?? didn't think so.

Reply to
Steve

Hi Steve,

I actually read the operating manual for the thermostat. when we acquired the house, the furnace did not come with an operating manual (its been through two owners). I just forgot the step of tagging the wires when changing from the old thermostat to the new. I was able to test each wire of the thermostat and determine that it was hooked up correct (no shorts) and traced each wire from the thermostat from to the actual furnace. I was also able to adjust the temperature of my fan limiter to have the fan shutoff after a reasonable time frame so that issue is fixed. But the fan still does not work when I switch the thermostat to the on position for the fan.

any ideas here?

------------------------------------- James Kirkby

Reply to
JKirkby

Its not wired correctly, and the thermostat(if digital), is not set up/programed correctly. Call somebody who knows WTF they are doing before you fry the transformer, and/or control board(s)

Reply to
Steve

------------------------------------- [URL=

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- Get a new energy efficient programmable thermostat today from ProThermostats.com. We\\'ll help you find the right thermostat for your home

Reply to
prothermostats

thermostat - Get a new energy efficient programmable thermostat today from ProThermostats.com. We'll help you find the right thermostat for your home

Reply to
prothermostats

Lets see. Prothermostats has his own web site, and he's posting through Sucuko company. I sense a small business start up.

Reply to
Stormin Mormon

Welcome to my killfile, spammer.

Reply to
Noon-Air

Anyone remember the rectum that used to sell Smart Thermostats here long ago? Friend of Paul, i think. ;-p

Reply to
Don Ocean

Easy now, boy .....

Reply to
.p.jm.

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