Are Gas Stoves Efficient?

[joem32543]

A little explanation first..

I live in an old farmhouse (1880) in Maine that was added onto in the early 2000's. When they renovated they installed underfloor radiant heating on the first floor and baseboard on the second floor. In the new areas, the radiant floor heat works great and you can feel the warmth on your feet. In the older part of the house, it does not work great and has trouble keeping up with the thermostat (I have it set at 64 and, when it's cold, is consistently at 61-63.) I think this is due to the radiant tubing being installed below the old subfloor, which has two layers of subfloor and a new hardwood floor that is ~2" of flooring for the heat to work through.

The house is approximately 3,000 s.f. between two stories. We close off two upstairs bedrooms and two downstairs rooms in the winter to allow the wood stove to heat the space we use better.I currently have a Jotul F 600 wood stove that I installed this year that we use to supplement the radiant heat that we keep at 64.

Will all that being said, I am interested in installing a Jotul GF 600 natural gas stove to heat the old part of the house that is currently being inefficiently heated by the underfloor radiant heat. This would be used in conjunction with the wood stove, but would primarily be for use when the wood stove is not in use. My question is, is using a gas stove in this way efficient? My thought is that I would disconnect the radiant heat zone for the old portion of the house.

 

[DAKSY]

That Jotul GF 600 is a good unit. It'll give you about 32K BTU (output) of heat.
Whether or not it'll heat well, depends on the insulation in the area you want to use it.
32K will heat about 800 sf with average insulation (2x4 walls w/R-13). More insulation
will allow it to heat a LITTLE more, but I'd say not more than 1000sf...

 

[joem32543]

The walls in the old part of the house have no insulation. The windows have been replaced and the house is pretty well sealed, but there is no insulation at all in the walls. The basement and attic have been insulated with closed cell spray foam. With not knowing the specifics of my house, would you say heating with a space heater (the gas stove) is more practical than trying to use underfloor radiant heat that is trying to heat through 2" of subfloor/hardwood flooring? Currently, I'm worried that trying to heat up the old portion of the house with the radiant heat is causing my boiler to run more more than it would otherwise. I just don't know if the cost of running a separate gas stove would cost less than increased running time of the boiler.

 

[DAKSY]

Does the radiant floor tubing have Insulation below it so the heat is forced into the wood?
Once the wood gets warm, it should hold the heat for a while.
The Gas Stove will heat the air in the space (room) it's located in,
but if there's no insulation, the heat is going to be wasted as it escapes.
Sounds to me like your first course of action is to insulate, so what ever heat
you're producing stays INSIDE the house.

 

[barmstrong2]

Check with the installer of the radiant robes. You may only need to increase the temperature of the upstairs radiant with the mixing controls at the boiler. This would require no increase in fuel use, just a tweak in controls.