I have a gas fire place with a simple on off button on the fireplace face. I purchased a Honeywell programmable thermostat but I am a bit perplexed with the wiring. I have done some research regarding this matter and found a post indicating the two wire connections are the TH/TP to R and TH to the W.

I have two questions...

1. In a standard furnace installation, there are at least 5 wires. Is this lack of connections, going to cancel out some functions? i.e. programmable function? And if so, are there other wires I should look for to fill these connections?

2. Am I safe to run new wire from the fireplace front to a different location in the room? Just add onto it?

Thanks,

Nan
:o

I have a gas fire place with a simple on off button on the fireplace face

Unless the fireplace was originally designed for a Honeywell thermostat it will not work without some adapting. There is more to a thermostat operation besides hooking up wires. Low voltage power supply of the correct voltage 24 volts,separate isloation relays and a common wiring link that is the standard of the heat and A/C industry.

You might be able to get the thermostat part to work but you will need to

Check voltage present at the fireplace and see if it is compatible with the thermostat.
Add a isloation relay that the thermostat will trigger the fireplace from etc.

If you have a wiring diagram of the fireplace it will make it easier to figure out.

I also believe that I would contact the fireplace manufacturer and check with them to see if this (added thermostat/wiring etc) will violate the UL/CSA listing on that unit.

Since I have no wiring diagram available I can be of no further assistance. Sorry

OK, I was hoping is was not WAY over my head, but I think this is best to leave up to an expert. I have a guy coming out from a fireplace business to help me with just this scenario. Thought I would get a headstart and see if I could "do-it'myself". It's a lot more complicated than putting in a cabinet or something like that.

Thanks so much for the response

Nan

You will most likely be told that you need a millivolt compatible thermostat. Should still only need two wires. If you find a programmable thermostat that is millivolt compatible, it will be battery operated, so when the batteries die, the fireplace with shut off.

Hey Dad77;

That is good and encouraging to know. I bought the 5-2 programmable Thermostat specifically because it states on the back that it is compatible with Gas Fireplace. But when I go to read the instruction for new or replacement instructions, it only refers to the 5 and 6 furnace labeled wires. I do not see any reference to it being millivolt compatible.

I just got the owners manual for my fireplace and it stated the electrical requirements is 120 volts.

WAIT... in here too... is
"SAFETY: AGA Certified Pilot Genator, Millivolt System activated with switch, remote control or Thermostat. "

I did not get the remote at the time of installation. Does this help?

OH, I guess seeing that my fireplace is Millivolt does not answer if the thermostat is. I am not sure how to find it out other than call Honeywell. They are not opened today as I have already tried. :)

OK, I found this site that apparently sells this product. Does this have enough information in it?

5-2 Day Deluxe Programmable Thermostat RTH6300B by Honeywell - Honeywell Central

It refers to being 750 millivolt compatible.

I might be getting closer... :)

Quote:

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Originally Posted by Naneegote

Hey Dad77;

That is good and encouraging to know. I bought the 5-2 programmable Thermostat specifically because it states on the back that it is compatable with Gas Fireplace. But when I go to read the instruction for new or replacement instructions, it only refers to the 5 and 6 furnace labeled wires. I do not see any reference to it being millivolt compatable.

I just got the owners manual for my fireplace and it stated the electrical requirements is 120 volts.

WAIT.... in here too... is
"SAFETY: AGA Certified Pilot Genator, Millivolt System activated with switch, remote control or Thermostat. "

I did not get the remote at the time of installation. Does this help?

---

This thermostat will work with your fireplace. All you need to do is hook the two wires from the (th-thp) on the gas valve of the fireplace to the (r-w) on the thermostat and you should be good to go. Please let me know if this helps, and good luck.

It WORKS!!

I have been only able to test it about 2 feet away but the timer and the on/off switches work. I need to wire it externatlly around my basement, but it is OK. I can go along the top and hide it pretty well.

Can I use really long wire or is there a limit to the length that I should use. I want it on the other side of the room as the fireplace is on the end of long rectangular room.

I am so excited...

Thank you so much for your persistence to help me...

Nan

Glad to hear its working.

As far as the maximum length of wire goes, I can't say for sure. I would string out the amount of wire required to reach the spot you plan to mount the thermostat at and see if the thermostat works. If it does, then you should be fine. Since your thermostat is battery operated, you should be able to run a very long distance without problem. Hope you enjoy your fireplace(wish I had one)..

Again, thanks.

I have enjoyed it for many years with just the on and off switch. I am having to rent out my basement and don't want a tenant to have to leave the heat on unnecessarily. So, I then remembered the I could get a thermostat for it. I heard that the remote thermostat costs about $180 and then I would have to get it from a dealer and that was about 6 years ago. I made an appointment to have him come out and talk options. His house call and the equipment, very expensive.


I started to think that I am a do-it-yourself kind of gal and so why couldn't I figure this one out. Went to Home Depot, spent $50 and was blessed enogh to find you and WaLa... I have a very cool working Programmable THERMOSTAT.

You're awesome.

Thanks so much.

You made the right move. I have found nothing but problems with remote thermostats.

mygirlsdad77, my pilot stays lit, and when I turn thermostat on wall "on" my blue pilot flame runs along the burners right to left, but doesn't give me a full, real flame. So I'm not sure if my main burners are lit or not. Any ideas why I can't get fireplace to light up like last winter?

Please post this question on a new page. That way you will get more anwers from more experts. Sounds like your burners are lighting, but not getting full gas pressure. Do you know how to check gas pressures? Please do start your own post.

Sorry, I did make a new post but nobody was answering so I put it here because I saw you were actively answering questions for people. No, I don't know how to test pressure. Plus, if it turns out it is low, which it probably is, which part would need replacing. The main gas is turned all the way up, so I don't know if something is only partially opening. I wish I knew my terminology better.

Are you on propane, or natural gas? You might not need to replace anything. You may be able to adust gas pressure. However, I would recommend calling in a pro. They will be able to locate the problem, and hopefully fix it at minimal cost. Sorry I can't advise you on how to check gas pressures if you are not familiar with it(to much liability).

Please let me know how this all turns out.

Update, my friend (gas fitter) and I opened up the pipe which leads to the main burner to find a spider web clogging inside at basically 99%. Which would explain why but burner did light but stayed a small blue flame. So we gave everything a good cleaing and voilà! So thanks again for all your help. All is good!

Damn spiders. Just glad you got it fixed. Sounds like you owe your friend a case of beer, Or (if he is like me) a bottle of whiskey. Take care.

Do these instructions work with a wireless thermostat?

THANKS MYGIRLSDAD!! I bought an Emerson Sensi Wifi thermostat and connecting it as you suggested to my millivolt fireplace worked! I couldn't find any useful information anywhere telling me how to hook it up. Thanks a bunch!!