Adding a wood stove to an oil furnace
I have radiant water baseboard fired by a summer/winter hookup oil furnace. It was just serviced this spring, excellent job by serviceman-efficiency went up 25% easily. However since oil is soon going to cost me $3 gal (SE PA, only a slight exag) I’m thinking of adding a backup system to heat the house, at least a helper system to reduce oil consumption. My serviceman (great guy, just got his masters degree in plumbing) suggested a wood-burner that would hook-up to the furnace water plumbing and also heat the water. I’m not sure if pellet or log or both. Wood around here ranges from $20 for whatever you can haul off in a pickup to $100/cord presplit hardwood. I have no problem splitting and sawing logs, could use the exercise. Was wondering if anyone else had any experience with such a setup? My other option is a standard wood stove in the living space cramping a small house. Plus the stovepiping seems to cost 50% or more as the burner itself (the stove wood[sic] be on the first floor, vented out the side then the stack rising up above second-story and roof, a bit of piping)
As a note, my home has a 2’x2′ square patch in the hardwood floor in the archway b/w living and dining rooms that my neighbor tells me was once a grate to let heat from an original coal stove radiate warm air up into the living space. I could easily replace that grate to get whatever additional warmth from a basement stove.
Any thoughts and/or experiences would be greatly appreciated.
Replies
That's $3 this year...
I'd be thinking about a different boiler with your fuel oil as a backup if you don't mind the wood acquisition. There are outside boilers from several mfgs which keep the wood supply out of your house. Others need a shed around them. You maintain thermostat control of the heat.
Sounds like your house is too small for my surplus boiler, which takes up to 4' logs. Turned out to be too large for my needs too.
Standard wood stove is going to be the cheapest to install, if that's a primary issue. Basement keeps the mess out of the living space, assuming an available flue.
PAHS Designer/Builder- Bury it!
Can I tie into the oil furnace's flue or is that asking for trouble?
No expert here, but far as I know, you don't mix fuels in a flue.PAHS Designer/Builder- Bury it!
In most cases, no, you cannot combine fuels. Not only the mix of fuels but the compromised draft if the flue is too small for both can leave you with CO gas in your house.
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I've got a hydronic system heated by a wood stove. The Pacific Energy wood stove is in the basement. It has a ss water coil in it. The design has a pump and aquistat so that when the water in the coil or rather in the tube just outside the coil reaches 140 F a pump kicks in and pumps the water into the storage tank. A separate pump ciculates the water through the radiant heating system. On colder nights -15 F or winter nights the electic heater in the storage tank kicks in as there just isn't enough heat transfer from the woodstove to cover off the heat loss . This year I'm setting up a closed loop heat transfer from my gas domestic hot water system.
The stove pipe was more expensive than the woodstove.
It seems the chimney pipe is looking to be as expensive or more. It looks as though I'm going to need about fifteen foot. The accesrories are looking to be about $300 plu $70 per three foot section of chimney. I found an old fashioned wood burner for less than $200 but not sure how efficient. I have to look into the water heating unit unless I Monster Garage it!
Don't do the Monster Garage thing to it, insurance is expensive enough with a new listed wood burner in the house.
I would think that a modified unit would get your policy cancled.
I have an oil/hot water furnace, with a wood furnace twinned into it on the same chimney.....legal in Canada as long as the wood furnace is CSA approved for that installation, and I think the oil furnace has to go into the flue above the wood furnace, but i may be muddled about that. Just put the new furnace in a couple of years ago, and had the whole system redone then, and the heating guy was careful about checking the whole thing was approved. The wood furnace was to be mostly a back up for when the power went out, but may get a lot more use this year.
Also have a smallish Pacific Energy stove on the main floor on a seperate chimney. When I bought that stove (excellent), replacing an older one, I thought about moving it to vent out the side, with the chimney running up the outside......I was very strongly warned against it by the dealer we bought the stove from. He won't do it unless the client insists. I trust his judgement, and he prevented me from doing something else not so wise.Cabinetmaker/college woodworking instructor. Cape Breton, Nova Scotia.
What were his reservations about side-venting? He didn't think a stack bracketed to the house was safe? I'm thinking (and I need to check) that I have to run a stack that is 4' higher than the roof. Did he think you were running something shorter?
I was looking at a couple of options...my house has a gambrel roof, and one option was to take the chimney out through the back wall and up through the roof where because of the gambrel, the run of chimney required to get the necessary legal claearnace would be short....hard to describe, but anyway, the top of the chimney would have been well below the peak of the roof. Not a very smart thing to do, so he talked me out of that......wouldn't give me any kind of odds on getting a good draw.
Next option was out through the side wall, up the wall and over the peak....this would have a long run of chimney on the outside wall. His experience was that this does not work well at all in a Canadian winter. Now, I see examples of this all over the place (my furnace chimney is installed like this), but I'm not in the business, and I'm not involved with installations five days a week like he is.I think he's a smart guy, so I bowed to his experience. We kept the existing chimney which runs up through the middle of the house to the peak. Not ideal as far as locating the stove in the room, but the draw to the stove is excellent.
Just checked my furnace set-up and the oil furnace does enter the flue above the wood furnace. Like I said, we checked this out pretty thoroughly, and the installation is legal as long as both appliances are CSA approved for it.
Cabinetmaker/college woodworking instructor. Cape Breton, Nova Scotia.
Edited 9/17/2005 2:21 pm ET by Adrian
My home is a gambrel as well. If the stove goes in the basement, then I could bracket the stovepipe to the chimney itself. Would be much easier if I could twin into the chimney itself though. If I put the stove in the living/dining, it would be on the opposite side of chimney beneath a bedroom. Can I jacket and wall in the stovepipe as it runs up through the house or bad idea? I could use steel studs and cement board or fireply or fire rock or whatever...
My woodstove chimney runs through a drywalled chase in an upstairs bedroom.....double wall stove pipe up to the chimney (through the ceiling), then a commercial Selkirk type chimney above.
Talked to an electrician I know yesterday....he's thinking about a wood furnace twinned into his oil furnace chimney. He's already run all the specs through his insurance company, and got the go ahead.Cabinetmaker/college woodworking instructor. Cape Breton, Nova Scotia.
Will check with insurance agent, good thought thank you.
a. Separate flue.
b. Go for it, oil will likely not get back under $1 again any time soon. Heated own house (5300 sq ft) with wood for 28 years until DW got tired of loading and splitting and cutting up pallets <G>. Custom install, about a hundred feet of pipe in fireplace (6 ft t 2 sided triangle) with doors circulated thru 2 AC evap coils in ducting. A few problems over the years with pipe corrosion in the ashes, but stainless pipe in those locations fixed that.
c. query, what is a "masters degree in plumbing" , thought that was an MSME?
perhaps an MSME is what he meant, whatever he seems to know his game, is polite, straight forward and works quickly.
I'd be interested if you come up with something. This sounds very similar to what my father tried about 20 years ago. He had baseboard heating and actually drilled through the sides of a wood burning stove insert, built a rack for the wood to rest on out of copper piping (that was one problem as he kept melting those connections) and heated the water which then went back into the system, back to the boiler and helped with the whole heating issue in the house. The also had a problem with super heating the water and blowing a T&P valve he had set up for just such a problem. In theory it seemed like a great idea. I'd figure there must be something built out there than can be used for this option.
Like you said with oil prices going out of site I'd love to find a way to actually do what he/you seem to be trying (I've got a lot of wood in my backyard right now).
In my situation I've got my oil burner and fireplace chimney on separate flues (same chimney). I thought about putting a wood stove in the basement and using the fireplace flue. Not sure it is safe however to put a stove in the basement as it would be between the boiler and the actual oil tank (I guess I could move the tank outside, although I'm not sure where I could put it). Best option would be similar to what my Dad tried and putting an insert in the 1st floor fireplace and heating through that.
I'd definitely appreciate input from anyone.
Tom
The best systems I have seen mentioned combust the flue gasses coming out of the wood boilers to achieve relatively clean combustion and high efficiency. The technical term may be 'gasification' systems, IIRC. None of the alternate fuel options are inexpensive - yet. However, we may see a "regression" to coal systems in some areas like PA that are close to plentiful coal supplies. Up here in the NE, I doubt that we'll see coal in residential use anytime soon.I would spend the money that youy set aside for an coal/wood boiler on insulation instead. It's a surer payback and much less problematic. Dense-pack cellulose or even exterior sheathing are relatively inexpensive ways to make walls tight and resistant to heat transfer. Retrofitting quality storm windows like Harvey Tru-Channels is another way to reduce infiltration a great deal. Weatherizing all other penetrations into the home are yet another step into the right direction.
Edited 9/29/2005 1:05 pm ET by Constantin