Wood stove radiant heat!??!

[bennelson]

Yeah, I think I will be insulating the crawl-space with rigid foam this summer.

I am mostly limited by the size of the small access panel I have into the crawlspace.

But once it's insulated, should keep the place warmer all winter.

[rbhollabaugh]

I saw something on the internet a couple years ago called hydro-coil. It was a heat exchanger you put into the firebox of a wood stove. I could not use it because my woodstove is too small.
I just did a search again for it and came up empty.

My neighbor was talking with a pellet stove maker and they claim to be coming out with a line of pellet stoves with a built in water heat exchanger. Sorry, don't remember the brand.

[bennelson]

Yeah, I have heard of those before.

My stove is tiny - it barely has room to put wood in it, let alone a water-pipe coil.

It sounds like the best way to go is to wrap a coil of copper pipe around the base of the chimney pipe.

I measured my crawlspace, how many feet of insulation I would need, and the cost.

It looks like for about $900 I could fully insulate my entire crawl-space (think a concrete basement that is only 2-feet deep), using rigid pink foam.

Right now, the crawl space is pretty cold - 55 degrees? That is where all the air for the furnace comes from, and all the air from the cold air returns go to.

If I fully insulate the walls and floor of the crawlspace with 2" of extruded polystyrene, I should be able to have it the same temperature as the rest of the house.

Then I will start saving on my gas bill the rest of my life (or however long we are at this house)

I should also be able to set up some hot water in the crawlspace for my Polish Hydronic System.

[rbhollabaugh]

You may want to consider using PEX tubing stapled to the underside of the flooring - above the insulation.
And you'll need a Taco pump such as the 007-F5, expansion tank, fill valve, shutoff valves, air separator, thermostat, and I'd probably use Prestone RV antifreeze just in case you leave the house unheated at anytime.
But and the big but here is you need to know how many BTU you will be getting from the wood stove in order to design the system properly and to know if it'll actually produce enough heat to warm the floor.

[bennelson]

I was definatly considering PEX tubing.

As for all the other parts, they get complicated real fast.

I would like to do a system similar to the "Solar heating plan for any home" in the Dec2007/Jan2008 issue of Mother Earth News.

It is an "open" system using a 4000 gallon tank built from 2x4s, plywood, and rubber roofing.

I would use fairly simply thermostats/pump controls for the project. Unfortunately, I would have to use the bronze Taco pump, which costs 2 and half times more than the cast iron one.

The other upside to a simple heat source running to a big box of water to some PEX in the floor is: I could add other heat sources to the design easily - such as a couple solar panels.

[Who]

don't use prestone in a heating system... ever

there are antifreezes made for heating systems although any antifreeze reduces how many BTUs each unit of water can carry...

[bennelson]

Because everything would be inside the house, and insulated, there would be no need to use anti-freeze. I would keep it all just plain water.

Plain water carries lots of heat, and it easy to add to, top-off, etc.

[Ryland]

you are lossing heat up your chimney, lets say your chimney loss is 30% of your heat from fuel, if you have a heat exchanger on the back, top or side of your stove, you are still loosing that heat up your chimney, that is why those air heat exchangers that go in the stove pipe and blow air thur work so well, and seeing as how one of my side jobs is cleaning chimnys, I would advise you to check it more often if you do anything to capture that otherwise lose heat, as creosoot buildup can increase, but with a straight run of chimney it's easy to check and should be done once a year, more often if you add stuff like you are talking about.

between useing ridgid foam, and spray foam, you should have your crall space really well sealed, insulating it from the outside is alwas but invalves more work as you have to dig down a foot or two all around your house, but for example, I did a 25 streach of wall, 2 feet down by my self in about 5 hours, that way the mass of your house foundation stays warm, insted of cold.

[Big Dave]

I feel your pain, dude. I too have a wood stove. It is an old fisher Papa Bear. Good stove – excellent quality materials and workmanship. Problem is that it was designed and sized for the house before I did the Bob Vila thing to the house. Before I renovated the stove was OK in the great room. But the house was almost completely uninsulated, so when I renovated, I insulated the house like a thermos bottle. Now the Papa Bear runs me out on all but below-zero days. The stove has so much heat transfer area (stove is about the size of a desk) that if you build a small fire it goes out – snuff by heat removal. If you build a fire that stands up to the heat removal you have a blast furnace and it runs me out of my well-insulated great room. This rascal is quite capable of eating up a cord of firewood in four days if I could get the heat to the rest of the house.
What I’m thinking of doing is welding some PlateCoil http://us.tranter.com/phe/platecoil/platecoil.htm onto the back and side of the stove. I would use a hydronic pump to move water heated in the PlateCoil to coils under my bathroom floor. Or alternatively a fan coli unit in some other room. I have a basement so this is easy work.

Just a matter of moving the heat where you want it.

[diesel_john]

the furnace fan should have several speeds, select the highest speed compatiable with your noise requirements. run the fan 24/7, remember the heat from the fan motor stays in the house its not wasted. the fan should be 240v for max efficiency. insulating the crawl space is worthwhile, seal air leaks first with foam, you mentioned you have a high water table, it doesn't get any better than that, you have an unlimited supply of heat right under your feet. geothermal heat pumps are very efficient. you get 3 to 5 times the heat out from the energy you put in. the heat pump is in the air handler so that heat stays in the house also, you can use your NG for backup. the geothermal heat pump is ideally suited for northern climates and it heats your hot water all year round but almost for free in the summer if you air condition for temperature or humidty. climatemaster is one company, there are many now. these systems are no more difficult to install than central air. there are slinky coils that can be buried in a trench,shallow well, or lake. i can see the time when wood burning outside of power plants will be discouraged if not out right illegal. you could be losing more heat up the chimney than your gaining unless your combustion air is automatically controlled and comes from outside. reguardless of you heat source non toxic antifreeze (like sierra) is required in any system that could leak on the ground, treated water has scaling concerns, and freeze protection is a must in your climate. sorry, a good news/ bad news viewpoint.