Installing 24 volt WiFi Thermostat on millivolt stoves

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THe CI-800 does not have good data logging like the other wifi T stats that is the only problem with it, and you can;t stop the schedule, you have to put it on hold mode, but each time you turn the stat off you have to put it back on hold mode, sucks. I;m testing it a few days now it works fine, but I;m not sure if its a good idea to inject 24v into the millivolt contacts?


Last year I ran 24 volts to the contact on the stove and it worked... this year it didn't work. I had to install the relay like everyone is suggesting. Not sure why it worked last year and now it wont..But the relay is the best way to go... maybe something in the board got damaged, but its working perfectly on the relay.,.
 
Just curious...what's the purpose of the relay? I have a wifi t-stat hooked up my oil burner and central air. My C-Wire didn't have enough voltage to power the t-stat, so I used a transformer to power it. It's been chugging along fine for a few years. Couldn't the same be done for a wifi t-stat on a pellet stove? Hook up the two t-stat leads from the stove, power with a transformer...good to go? If I'm missing something, feel free to chime in.
 
Just curious...what's the purpose of the relay? I have a wifi t-stat hooked up my oil burner and central air. My C-Wire didn't have enough voltage to power the t-stat, so I used a transformer to power it. It's been chugging along fine for a few years. Couldn't the same be done for a wifi t-stat on a pellet stove? Hook up the two t-stat leads from the stove, power with a transformer...good to go? If I'm missing something, feel free to chime in.


Usually on pellet stove you usually just close a contact, you actually dont feed power into it like 24v on a normal furnace or AC unit.to turn it on. However not all pellet stoves are the same, this is way mine is made anyway..
 
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Is it possible to install Honeywell RTH 9580 Wifi Smart Thermostat to Quardafire Mt. Vernon AE Pellet Stove (with thermostat controled 3 Wire Red, green and White)?
 
Hi all, have a current 2 wire millivolt Napoleon gas fireplace for summer home, heat only no AC. I am interested in installing the Honeywell wifi thermostat RTH9580WF sold at HomeDepot and have also heard that this stat may be able turn on my millivolt system without using a Relay. Similar to bjosephwombat. I plan to add 24volt plugable tranformer. I know Honeyewell mentions in the user manual this termostat do not work with millivolt system. Though I wonder if that is just because it requires a 24volt transformer, not able to get straight answer out of them as to why it would not. A couple of questions.

I plan to connect like this:
Transformer wire: White (24v) transformer wire to C and black (0v) transformer wire to RC of thermostat
Heat system wire: White wire to W and red wire to R on thermostat

Question:
1. Do I really need to remove Jumper from RC+R? I do not have any other elements such as AC, just heat only system.
2. When the heat turns on from tstat what voltage should I expect to see coming from W and R on thermostat to the fireplace gas valve?
3. Do these 24 volt thermostats actually send voltage to the millivolt valves or just close circuit to start heat system?
If you aren't using AC then you just need a wire Rh. When calling for heat the Rh and the W power the thermostat. When the heat is not calling, Rh and C power the thermostat. The deal with 3 wires running to this is that there always has to be a return to common for the tstat to have power...for the wifi, date, time and whatever other things it comes with. I suppose one could use batteries too but you need a lot of them to get 24v
 
Why not just hook up a 24 Volt transformer to RC And C this will power the thermostat just fine!
Take the jumper out from RC And RH, Hook up a wire from RH and W back to the pellet stove to make the stove work and you are done. No need for relays etc.
 
Why not just hook up a 24 Volt transformer to RC And C this will power the thermostat just fine!
Take the jumper out from RC And RH, Hook up a wire from RH and W back to the pellet stove to make the stove work and you are done. No need for relays etc.
This exactly how a technician from Honeywell answered my question when I called them today. Just want t make sure. I don't want to blow my stove control board. Cost $450 or more.
 
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Pilo,
Keep us posted and post pics. That's a very similar setup to what I'm looking into.
 
Found this on another site.
 

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Found this on another site.
Arti,
Nice find.
I am going to connect my mt. Vernon to the new rth 9580wf exactly the way it showed in posted picture.
I have an extra Green Wire. I am assuming it will connect to terminal G.
This my first year with Quadrafire Mt. Vernon AE Pellet stove. I can't stop myself looking at it. This stove is beautiful.
I read all the reviews Some good some bad.
My stove is made in 2008 AE model. What a beast. Uses almost no pellet and puts out so much heat. It is unbelievable It heats my 2 floor 2000 sf house nicely. Living room cozy at 72F other rooms even the ones upstairs are 68-71 F.
My wife thinks I am obsessed with this stove. How can I not br.
I was buying oil 5 or 6 time every winter around $800 every time. Close to $5000 for heatng every winter. I am saving tons of money.
I have 3 tons of hardwood pellet in my basement. All set,
Stove used 5 basis of pellets in 13 days. I know it is not very cold yet.
Even I use a bag a day (I don't think I will) I am still saving tons of money.
3 tons of pellet cost me $750 plus $85 delivery and 4 hours of involuntary exercise (putting the pellet in my basement)
Feels Goo.
I can kiss this stove. No kidding. Bye bye oil man.
 
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Why not just hook up a 24 Volt transformer to RC And C this will power the thermostat just fine!
Take the jumper out from RC And RH, Hook up a wire from RH and W back to the pellet stove to make the stove work and you are done. No need for relays etc.

Hi guys, thanks for your posts and responses, really helpful. Special thanks to Scott for starting this great post and for all the informative info. I'm in Canada and I've gotta say Honeywell tech support has not been helpful at all with connectivity options with the RTH9580WF. It is advertised as NO support for millivolt systems and they offer no further options to make it work. I'm quite sure it would work using 24v transformer and relay. Though would prefer just using a 24v transformer if possible.

I actually have the YTHX9321R5079 Prestige 2.0 installed using the Redlink gateway for 3 years now and I am extremely happy with it. It is controlling my millivolt gas fireplace and I just found out the reason its working is that the W terminal on the Prestige thermostat actually has "Heat Relay" built in! So that is why I was able to get it to work first try. I wired the Prestige same as indicated above in my first post as well as the way Arti indicated, I did not need to remove the RC/R jumper though. Honeywell indicates the RTH9580WF does not have "Heat Relay" built into the W terminal so that is why I thought may need to add external relay. But if just removing RC/R jumper may do the trick that is definitely worth a try.
 
Is it possible to install Honeywell RTH 9580 Wifi Smart Thermostat to Quardafire Mt. Vernon AE Pellet Stove (with thermostat controled 3 Wire Red, green and White)?
To best of my knowledge, no 3rd party stat will work on an MVAE, because Quad (stupidly, at least for the customer) put half the brains of the stove itself in that flaky, third rate wall box they call a stat. Love my MVAE. Despise that stat.
 
I am going to connect my mt. Vernon to the new rth 9580wf exactly the way it showed in posted picture.
I have an extra Green Wire. I am assuming it will connect to terminal G.
This my first year with Quadrafire Mt. Vernon AE Pellet stove.
Don't do it.
The Mt Vernon AE controller is not a simple thermostat. It is a digital control system that operates at 3V. If you connect a 24V transformer to the stove you will likely do damage to the control board in the stove.
 
I don't think he would be connecting the 24v to the stove, it would be to the wifi thermostat. As mentioned, that's how I run mine on my home HVAC. It's to power the wifi radio in the t-stat itself. You can use batteries, but you would be changing them out daily. Wifi uses some juice.
 
I don't think he would be connecting the 24v to the stove, it would be to the wifi thermostat. As mentioned, that's how I run mine on my home HVAC. It's to power the wifi radio in the t-stat itself. You can use batteries, but you would be changing them out daily. Wifi uses some juice.
I see, my miscomprehension, But in any case a relay will not control the MVAE. At best it will do nothing, at worst it will short out the 3V supply.
 
I see, my miscomprehension, But in any case a relay will not control the MVAE. At best it will do nothing, at worst it will short out the 3V supply.

That certainly is an interesting setup those stove use. A wifi t-stat seems like it would be a real challenge to install. If even possible.
 
I came across this blog today and I thought others might be interested.
 
I'd like to thank both Scott and Don for giving me a good laugh today. I'm new here so I don't know all the players, but it's kind of obvious that the folks in the business are a little bit busy and stressed. I really do appreciate the fact that they take time to help out all of us consumers with their knowledge and experience - but I would not want to be your shoes, guys. Not the week before Thanksgiving in New England.
 
Here's a pic of my wifi t-stat wiring. This runs our heat (hot water baseboard) and central air (air handler is in the attic).

The black wire in the c terminal and black with white stripe in the RH terminal are the wires from the transformer.

This is a 3m-50 I bought at Home Depot a few years ago. It has a touch screen you can use to make adjustments. But we always use the app.

With a pellet stove, I'm thinking you'll only see 4 wires: two from the stove and two from the transformer. I plan on hooking one up to my GCI60at some point this winter.
 

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A bit wordy, yes.
Of course it's wordy, it's a blog. He needs to impress us. I mean he has a real need to impress us (for whatever reason).
There are, however, some important details in there. The one that caught my eye was the comment about cloud server based thermostats. If your access to the internet is cut by the forces of nature, you have no control over your thermostat? That is insane. Technology run amuck. I want my control to be strictly local.
Don't get me wrong, I love high tech gadgets, but I don't want to lose control of my gadgets because of the weather or because some hacker found my thermostat on the web.
 
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Scott, thanks so much for all the info on this site. I would like to control a gas stove (milivolt system) in my vacation home through WiFi. Can I do this with the setup that you posted at the start of this thread? Are gas stoves and pellet stoves controlled the same way? Would I be correct in saying that a normal WiFi tstat won't work because there is no dedicated power source (C-Wire) available b/c I am on a milivolt system, therefore I need to put in the 24V transformer and relay? (I am trying to sum up your opening post to make sure I understand...) Then I can plug that in to an outlet, wire the rest, and be good to go? I AM using it as my primary heat source, since the other option would be to use the electric heat, which will cost me a fortune. Do you know if it is ok to use a gas stove as the primary source long term?

Again, thanks so much!
 
Scott, thanks so much for all the info on this site. I would like to control a gas stove (milivolt system) in my vacation home through WiFi. Can I do this with the setup that you posted at the start of this thread? Are gas stoves and pellet stoves controlled the same way? Would I be correct in saying that a normal WiFi tstat won't work because there is no dedicated power source (C-Wire) available b/c I am on a milivolt system, therefore I need to put in the 24V transformer and relay? (I am trying to sum up your opening post to make sure I understand...) Then I can plug that in to an outlet, wire the rest, and be good to go? I AM using it as my primary heat source, since the other option would be to use the electric heat, which will cost me a fortune. Do you know if it is ok to use a gas stove as the primary source long term?

Again, thanks so much!
stoves are not primary sources of heat. They are stoves and are considered decorative appliances. How you choose to use your stove is up to you. Yes, the system I have put forward would work on a gas stove too that uses a millivolt signal, though I'm not 100% how a gas stove generates the millivolt signal.