Even a modern mercury one should be able to increase the differential by using a slightly stronger magnet.

Mercury? Can those still be bought? I know California banned them. I remember when the plant I worked in here in Ohio declared war on mercury and all the mercury thermostats were removed and just as fast I removed the mercury bulbs in them. Great tilt switches. The use of the precision mercury in glass thermometers were also removed from service. I would like to believe I "liberated" them. Personally I am running with the two thermostats in parallel. Good luck finding anything mercury in anything modern mercury and modern are like an oxymoron.

Ron

 

Canada has banned the use of Mercury in just about all the traditional uses.
I recall when I used to make a few ££'s as a result of 'recovering' a fair amount of mercury when I would scrap a dud Ignitron!

 

Adding the extra hole in the wall could put me in an exwife situation, lol.

I don't understand why you would need to put any other holes in your walls? You said you have a return line from the room, right? You would use that return to a new blower and disconnect it from the furnace return plenum.

When I make a fire in the fire place I turn on the ceiling fan to distribute the heat into the hall way and thus into the other rooms. Should work for a wood stove too.

I can give you a more fun way of getting an exwife, the one that got me mine. Fun for a short while anyway.

 

older mechanical thermostats that were used with coal furnaces.

Mercury? Can those still be bought?

We were poor, our coal furnace was a gravity one and no thermostat. As the oldest kid guess who got to haul ashes and stoke the fire when the oldman wasn't home?

 

At least some of the furnaces had an electrically powered, thermostat controlled stoker, which was a device that forced coal into the firebox in response to a call for heat. This was the time long before mercury bulb thermostats, with bi-metal blade mechanical thermostats that used a small magnet to provide both the dead-band and the fast switching function.
And as for banning a material, it must be terrible to live one's life chained to the fears of people who are unable to see the concept of using a toxic substance safely. Perhaps they have been out in the sun too long.

 

At least some of the furnaces had an electrically powered, thermostat controlled stoker, which was a device that forced coal into the firebox in response to a call for heat. This was the time long before mercury bulb thermostats, with bi-metal blade mechanical thermostats that used a small magnet to provide both the dead-band and the fast switching function.
And as for banning a material, it must be terrible to live one's life chained to the fears of people who are unable to see the concept of using a toxic substance safely. Perhaps they have been out in the sun too long.

You must have been around rich people. Powered stokers weren't use in any of the homes in my area. The schools had them and I assume the stores that still used coal did. Stoker coal was sold at a much higher premium price than what home owners could afford. We and all of the people I knew used lump coal, not the crushed coal that stokers used.

Running a coal furnace was more than just stoking it. You also had to adjust the damper to control the air to the fire.

You don't live in a world where lead in products is banned?

 

I saw the stokers when I was about ten years old, MANY long years ago. Two families on the block had them. Some folks were rich, my family was not. But all of the kids went to the same public school. In that family the father had just started an electrical contracting company that was quite successful. And never saw the need to show off his money.

 

I made the purchase of the dayton 1UHG8 thermostat have installed and having a small issue. The existing thermostat is a ritetemp 8022c and 4C thermostat wire was pulled from the hvac unit. I then installed the 1UHG8 thermostat in the same room as the wood stove and pulled 3C thermostat wire from the ritetemp thermostat to dayton thermostat. The dayton thermostat is set to cool / fan auto with the intent being once the room with the wood stove gets too hot the blower fan on the furnace will kick on and distribute warm air throughout the house.

The issue: The system works fine when the ritetemp thermostat is pulled from the base. When the ritetemp thermostat is installed in the base the blower fan kicks on when the cooling setpoint is reached, however the outdoor units fan also kicks on. I've attached a schematic showing current wiring between the (2) thermostats and suggested wiring from each thermostat manufacturer. Thanks again all for your help up to this point. I'm hoping this is a simple fix.

 

What has happened is that when the second T-stat switches on to operate the circulation fan it is also switching on the AC fan connection. So the solution is to disconnect the fan control wire from that second T-stat.

 

Bill - Second thermostat being the dayton? Where do I terminate the green wire that is currently connected to the G terminal on the second thermostat? Or do I need to change the wiring on the ritetemp thermostat?

 

Bill - Second thermostat being the dayton? Where do I terminate the green wire that is currently connected to the G terminal on the second thermostat? Or do I need to change the wiring on the ritetemp thermostat?

Two thermostats for one furnace won't work. that's why I have said you need a separate blower to supply the heat from the wood stove to the existing furnace pipes. That way you distribute the wood heat and when the room where the original thermostat is, is above the call for heat it won't turn on.

 

There has to be a way to accomplish using 2 thermostats. Even if I have to add a relay with a 24vac coil, i'm pretty sure it can be accomplished without having to add a second blower.

 

For the T-stat controlling the furnace that you are using to distribute the heat, which is the one with the outside unit switching on, the rally simple thing to do is to switch off the power to that outside compressor unit. My guess is that since it has a compressor it probably is on a separate circuit from everything else. That will be simpler and more effective than any wiring change, and probably more convenient as well.
Of course, this is based on the guess that you do not need any cooling during the heating season.

 

Bill - I was thinking the exact same thing! Both thermostats are manual change over and I could just turn off the disconnect switch at the outdoor unit.

 

Bill - I was thinking the exact same thing! Both thermostats are manual change over and I could just turn off the disconnect switch at the outdoor unit.

Cheap and Easy!!!