24V Thermostat Wiring

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Rafter2S

Member
Sep 22, 2016
19
oregon
I posted last week about using a Honeywell TH830WF (24V) thermostat on my Breckewll Big E pellet stove. Attached is my wiring diagram for what I am currently wired for. I have 24 volts to my thermostat, but don’t seem to be getting any signal from the W terminal when calling for heat. If I use a jumper from my 24v supply to the white/yellow then the relay closes and turns on the stove. Any one see a reason I am not getting a signal from W while calling for heat?

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bogieb

Minister of Fire
Oct 31, 2014
2,989
South Central NH
I thought someone on that thread said you needed a millivolt capable tstat and that 24V one wouldn't work?
 

Former Farmer

Minister of Fire
Apr 12, 2008
608
NE Wisconsin
Did you try putting a jumper between R and Rc on the thermostat?
 

Rafter2S

Member
Sep 22, 2016
19
oregon
You need to figure out what terminals on the tstat act as the on off for heat. They will be the only ones that pertain to tripping the relay. What are the specs of the relay?

It is a RIBU1C relay.
 

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Former Farmer

Minister of Fire
Apr 12, 2008
608
NE Wisconsin
Try jumping the terminals R to W on the terminal block for the thermostat. Just take a short piece of wire and touch to both terminals. Checking to see if the relay will energize. If it does, it may be a problem with the thermostat. You can check that by seeing if there is continuity between the R and the W pins on the back of the thermostat when the thermostat is calling for heat.
 

railfanron

Minister of Fire
Nov 2, 2013
563
Perry MI
Just got my Harman running on an Ecobee 4 thermostat this week. Had to connect the 24v hot to the Rc to get it to power up. Had it on the Rh at first. Anybody thinking of doing this with 2 Ecobees (1 for your furnace and 1 for the pellet stove) there is a problem with programming the 2 for different comfort settings. If you set the home setting for 70 on one stat the other automatically sets itself to the same temp. Running the furnace and pellet stove at the same temps takes the stove out of the equation. I have all the vents shut down in the room with the stove but enough heat gets in there to keep it from coming on. I have an email into Ecobee on this. I have a workaround that appears to work. Change the thermostat temp reading moving 1 up 1.5 degrees and one down 1.5 degrees. This gives a 3 degree difference between the two but the reading on each is off by 1.5 degrees. Not really a lot but not ideal.
Ron
 
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bogieb

Minister of Fire
Oct 31, 2014
2,989
South Central NH
Got it working. Hand to energize the White /yellow wire with 24v. It’s nice to see have it on a programmed thermostat and have access from anywhere.
Glad you got it figured out!
 
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zrock

Minister of Fire
Dec 2, 2017
1,151
bc
interesting that they do not have a setting that is visible to run them as 2 separate units. Not sure how your home network is set up but if you have both 2 and 5g on your router try setting one up on each network. This way they are thinking they are in 2 separate homes and may not connect togeather
 

railfanron

Minister of Fire
Nov 2, 2013
563
Perry MI
Zrock The stats are on different wifi networks. That didn't work. I also tried setting them up on different house names with the same address. That didn't work either. I could create different accounts for each stat but that would be a pain logging into and out of the app for different accounts. Haven't got a word back from Ecobee yet. I guess this has them scratching there heads.
Ron
 
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railfanron

Minister of Fire
Nov 2, 2013
563
Perry MI
I would think this will get a fix. My thought is what if you have a mother in law suite. Mom likes to get up at 9am you like to get up at 7am. Mom likes her heat a little warmer (73 degrees) you like yours at 70 degrees. That's just one scenario there are probably lots more. A simple Linked/Not Linked switch in the app and the appropriate database for the second stat would be all that's needed.
Ron
 
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