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Comfort Specialist
Comfort Specialist, HVAC Technician
Category: HVAC
Satisfied Customers: 1368
Experience:  Master Lic. holder for HVAC & Gas, Contractor, Estimator, Designer, Air Balance Certified, LG Master Commissioner, UNC Cert. holder for Industrial Ventilation
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our honeywell th8000 will not stop the fan no matter where

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our honeywell th8000 will not stop the fan no matter where we set the temperature,fan,heating or cooling modes.changed batteries.thank you

Wvfan79 :

Hello there! I'm Norman but you can call me Norm. Let's see what I can do to get you some answers today. I'm ready to get started whenever you are.

Wvfan79 :

Hope you are doing well today.

Wvfan79 :

Please tell me, is this the outside fan or the indoor blower that continues to run?

Customer:

Hi Norm, Greg here and it is the inside blower on our electric furnace that continues to run.

Wvfan79 :

Ok, please pull the cover off of the thermostat and carefully remove the Green G wire. Tell me if the blower starts.

Customer:

haven't removed wire yet, but the blower is still on and you want us to check to see if the blower will start? Do not understand.

Wvfan79 :

No, sorry, typo

Wvfan79 :

See if the blower turns off.

Wvfan79 :

stops

Customer:

k. will do that.

Customer:

need screwdrivers first

Wvfan79 :

Ok, I'll be standing by. If the blower doesn't stop you can put the G wire back on.

Customer:

when we remove the thermostat cover, after about 30 seconds the fan will stop. So now what?

Customer:

should we still remove green G wire?

Wvfan79 :

Ok, that tells us the thermostat is actually keeping the fan on and the problem is internal to the thermostat. That's good, no need to pull the G wire.

Wvfan79 :

Now give me a minute to pull your thermostat manual so we can reset it.

Wvfan79 :

In the mean time please tell me which terminals on your thermostat have wires connected to them, like G, Y, AUX, etc.

Customer:

R, O/B, Y, G, C, E, AUX, S1, S2. these are all the wires connected.

Wvfan79 :

Ok, thank you. It appears the TH8000 doesn't have a hard reset. Please pull the batteries out and put them back in the thermostat in reverse for about 30 seconds, then put them back in normally. Set the fan to AUTO and the system to Off after you remount it. Let me know if anything changes.

Customer:

should we put the thermostat back in the wall, after reverse

Wvfan79 :

Yes please.

Wvfan79 :

Make sure the fan setting is set to AUTO and system set to OFF

Customer:

k. will let u know

Wvfan79 :

Thx

Customer:

So when we did the 1st reverse and wait 30 seconds, the fan still came on. After the 30 seconds we took the thermostat panel off and put the batteries in the right way and put the thermostat panel back on, the fan still came on. That is with the fan setting on AUTO and the system on OFF.

Wvfan79 :

So the fan relay is stuck internal to the thermostat, basically the fan switch inside is bad and stuck closed sending voltage to the Fan.

Customer:

so is there anything we can do.?

Customer:

The temperature keeps going up even though the system is off. Is this possible.

Wvfan79 :

If the fan is running it's likely picking up heat from the attic/crawl space and moving it to the space. This can happen when a fan runs constantly.

Wvfan79 :

To fix this the thermostat will need to be replaced. You may get lucky and find the same model at a local Lowes or Home Depot and just be able to snap it on this sub-base and be back in business.

Wvfan79 :

If they don't have the same one the cross reference should be straight forward. However, be sure to turn the main power off to the system before taking the wires off or re-wiring.

Wvfan79 :

Sorry just noticed you were in Canada, not sure if they have Lowes and Home Depots up your way.

Wvfan79 :

I will be standing by should you have further questions. I'm here to help.

Customer:

We will check to see if we can find the exact one to replace, and yes in Canada we have Home Depot. Thank you so much for all of your information and time. We were very helpful. Thanks again. Greg and Claudine in Canada.

Wvfan79 :

I'm sorry I had the rating system locked.

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