Wire to thermostat?

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Dillonmoeller

New Member
Nov 23, 2023
6
USA
My pellet stove has a 2 wire thermostat harness(not connected or hooked up)and a separate temp sensor harness. On the controller there is a setting for both. I would like to wire the thermostat harness into an existing thermostat in my house. I bought the house a year ago and the furnace never worked. The AC works fine. The manual for the pellet stove says that it will turn on when “asked” by the thermostat. I guess my main question is where would I land the 2 wires on the digital thermostat. I’m concerned about sending 24v back to stove and burning up the motherboard. I assume it is just looking for a switch to close, not to be activated by 24v. Thanks for your help.
 
Probably be a good idea to give the forum more information such as Brand and Model of the stove, be easier to help with that information.
 
ComfortBilt HP22i, basically trying to bypass furnace,keep AC working and hvac fan. Thermostat is an Amazon smart thermostat
 
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Yes, correct, you don't want to apply 24VAC to your pellet stove. The pellet stove external thermostat connections are meant for a contact closure, not for 24VAC. So, the standard 24VAC type of thermostat sends 24VAC to the "Heat" terminal when the room is too cold.

To use a standard 24VAC thermostat with your stove, add a 24VAC relay, the relay coil terminals go to the C and W thermostat terminals, and the relay "C" and "NO" terminals go to the pellet stove. The polarity of any of these connections does not matter. The relay isolates your stove from the 24VAC.


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Personally I’d just add one of these and find a temp setting that keep the the other thermostat off as much as possible.

Honeywell Home CT30A1005 Standard Manual Economy Thermostat - Heat Only https://a.co/d/33cJFeC
 
Yes, correct, you don't want to apply 24VAC to your pellet stove. The pellet stove external thermostat connections are meant for a contact closure, not for 24VAC. So, the standard 24VAC type of thermostat sends 24VAC to the "Heat" terminal when the room is too cold.

To use a standard 24VAC thermostat with your stove, add a 24VAC relay, the relay coil terminals go to the C and W thermostat terminals, and the relay "C" and "NO" terminals go to the pellet stove. The polarity of any of these connections does not matter. The relay isolates your stove from the 24VAC.


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Amazon product ASIN B07DHGXMLWthank you i will let you know how it goes, i ordered one of these and plan on hiding it inside of stove instead of in the wall
 
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Yes, correct, you don't want to apply 24VAC to your pellet stove. The pellet stove external thermostat connections are meant for a contact closure, not for 24VAC. So, the standard 24VAC type of thermostat sends 24VAC to the "Heat" terminal when the room is too cold.

To use a standard 24VAC thermostat with your stove, add a 24VAC relay, the relay coil terminals go to the C and W thermostat terminals, and the relay "C" and "NO" terminals go to the pellet stove. The polarity of any of these connections does not matter. The relay isolates your stove from the 24VAC.


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My thermostat isn’t sending power to my relay when I hook it up to c and w, and turn the heat on. The relay works when I touch it to c and r. Any advice?
 
My thermostat isn’t sending power to my relay when I hook it up to c and w, and turn the heat on. The relay works when I touch it to c and r. Any advice?
The furnace never worked you say? It’s not the thermostat is it?
 
Through all this i actually got the furnace to run fine lol. I had the r wire coming from the furnace landed to the Rc terminal on the thermostat. The wire was labeled Rc… but when I swapped it over to the r the furnace fired right up. Anyway still want to bypass the furnace. So I was able to get the relay to work by pigtailing the w wire that runs to furnace with one side of the relay coil. The other relay coil side is going to c. But when I eliminate the w wire going to the furnace and just put the relay coil wire in its place the thermostat won’t send power on it. It goes through a safety or check of some kind that the furnace is receiving a signal I assume before sending power down the w wire. I know it’s just a wiring issue I’m overlooking. Here is a photo of the furnace mb and the terminals in the thermostat. Thanks for the help

IMG_1107.jpeg IMG_1105.jpeg
 
Through all this i actually got the furnace to run fine lol. I had the r wire coming from the furnace landed to the Rc terminal on the thermostat. The wire was labeled Rc… but when I swapped it over to the r the furnace fired right up. Anyway still want to bypass the furnace. So I was able to get the relay to work by pigtailing the w wire that runs to furnace with one side of the relay coil. The other relay coil side is going to c. But when I eliminate the w wire going to the furnace and just put the relay coil wire in its place the thermostat won’t send power on it. It goes through a safety or check of some kind that the furnace is receiving a signal I assume before sending power down the w wire. I know it’s just a wiring issue I’m overlooking. Here is a photo of the furnace mb and the terminals in the thermostat. Thanks for the help

View attachment 319861 View attachment 319862
Really want to completely bypass the furnace so it won’t try to fire up every time. I can make it work right now just by shutting the gas off to it. But I would rather it never receive the signal to turn on.
 
Really want to completely bypass the furnace so it won’t try to fire up every time. I can make it work right now just by shutting the gas off to it. But I would rather it never receive the signal to turn on.
So have you ruled out a faulty thermostat??

Edit. Read more. Where is the 24v coming from? Are there any insured wires behind the mounting plate.
 
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