Wood Furnace in prefabricated chimney

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bbauer161

Member
Jun 27, 2015
25
Joppa, MD
Working on trying to solve my heating issue in the foreclosure I purchased last year. Here is what I have in my 2 story (with a basement), 3000 Sq ft, post and beam construction home.

Prefab chimney with two flues. One goes to the main floor to a zero clearance firebox (currently has a gas insert....the gas tank was taken once it changed hands...was a rental tank). Second flue runs to my basement where it is hooked up to my forced air oil fired furnace and also the oil fired water heater (see picture below).

Yes, oil prices are cheap but my goal is to heat the house with wood. I've got plenty of wood on my property. My goal is to install an add on wood burning furnace in the basement which will utilize the flue. Power vent the oil furnace and water heater directly outside from the basement. Put a pellet stove on the main floor that vents directly outside (so the flue running to the main floor of my house will not be used). The pellet stove would be for late fall and early spring when firing up the wood stove is too much.

Couple questions that I'm trying to figure out.

1) I'm not 100% sure what type of flue I have that is hooked up to my oil furnace/water heater. Do I need to replace the entire flue with Class A pipe or can I install an insulated liner down it and hook that up to the wood stove?

2) Can I power vent the oil furnace and water heater in one vent? Does anyone have an idea of what something like this should cost when hiring someone to do?


Please see the picture below for my current oil furnace and water heater.

IMG_0287_zpsdztcng9j.jpg

I'm trying to do all the research I can on wood furnaces. This stove is local to me and I went and looked at it today. Two years old. Thoughts?

http://baltimore.craigslist.org/grd/5429272483.html

Any insight on this would be great. Willing to pay some money to do this right....but trying to keep it reasonable as well.

Thanks!
 
As far as the flue is concerned , I'll leave that up to some more experience for your answer. The furnace I can tell you is pretty much identical to the Clayton furnace that was in my home that we bought this past spring. We have heated exclusively with it as it is the only source of heat ducted throughout our two story house. That unit certainly will keep your house toasty and most likely too warm ! Also be prepared to chew through some wood if you're running it full bore, mine eats a wheel barrel a day roughly running high demand. Also, have found best results with using the force draft only on startups to bring things up to temp then shut it off , leave it off and dial my spin draft on load door as needed. My flue has a strong draft and I don't really have an ideal set up to run a Baro-damper so we have made out well with just setting the manual damper like a typical woodstove. Best burn times I've gotten so far have been in the 6 hr range, with decent coal bed at 8 hrs for next charge. I Also burn soft coal occasionally in mine with wood to stretch burn times with good success as well as bagged anthracite coal when we will be away from the house for some time ( can get 24-36hrs out of an 80 lb charge of it before needing shaken and reloaded) They do not burn the cleanest either, so be prepared to sweep fairly often. All in all I would say you will be satisfied with that unit.
 
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I just remembered that I had a few pictures on my phone from when I had the chimney inspected before purchasing the home. I'm pretty sure its an 8 inch pipe. As you can see, there are some repairs to be done at the top of the chimney, including the top piece of the flue. However, this gives you some pictures of the pipe. I just noticed from the text that the person inspecting it said it was a triple wall pipe. Given that, I would assume if I put an insulated liner in it, I will be fine. Do I even need to put an insulated liner in it though (I plan to repair that top piece that is in rough shape). Any help is appreciated!

IMG_0370_zps6mfo8qif.png





IMG_0371_zpsyux5fwcw.png



IMG_0369_zpsovtbgmo3.png
 
As far as the flue is concerned , I'll leave that up to some more experience for your answer. The furnace I can tell you is pretty much identical to the Clayton furnace that was in my home that we bought this past spring. We have heated exclusively with it as it is the only source of heat ducted throughout our two story house. That unit certainly will keep your house toasty and most likely too warm ! Also be prepared to chew through some wood if you're running it full bore, mine eats a wheel barrel a day roughly running high demand. Also, have found best results with using the force draft only on startups to bring things up to temp then shut it off , leave it off and dial my spin draft on load door as needed. My flue has a strong draft and I don't really have an ideal set up to run a Baro-damper so we have made out well with just setting the manual damper like a typical woodstove. Best burn times I've gotten so far have been in the 6 hr range, with decent coal bed at 8 hrs for next charge. I Also burn soft coal occasionally in mine with wood to stretch burn times with good success as well as bagged anthracite coal when we will be away from the house for some time ( can get 24-36hrs out of an 80 lb charge of it before needing shaken and reloaded) They do not burn the cleanest either, so be prepared to sweep fairly often. All in all I would say you will be satisfied with that unit.


Thanks for the response and info. The individual selling it said the same thing about heating my home. He controls it using the internal rheostat and it is more than enough for him. He burns a combo of coal and wood as well. Said he gets 8-12 hours depending on wood type and how much he fills it.

Do you have a thermostat hooked to yours that you control it with?
 
So basically you need a new chimney. He is quoting almost $2,000 in repairs. If you go out the side wall you could put in a brand new stainless chimney for less money. Also you said you had 2 chimneys, the roof says you only have 1.
 
Yeah you cant run a wood furnace into that chimney It looks like you need a new one. If it was me i would run it up through the existing chase It is already there why not use it.
 
Yes mine was set up by the man I bought house from to the thermostat. Being new to a wood furnace and only experience with wood burning being a typical woodstove I researched and listened to the man I bought from. My experience on my set up is that it works best using it at startup or recharge a new load. The furnace would just smolder until the thermo kicks in calling for heat again and then blasts it full of air that sends my pipe temps up to 600 until thermo reaches 70 if left to go that route with my experience using it and I'm not too fond of that ! My unit has a spin damper on the load door, and a toggle switch on the combustion blower. I am able to control the blower at the stove then adjust my spin damper and after experience have found the sweet spot where it will cruise along throughout the day or night. works for me this way, best of luck for you !
 
So basically you need a new chimney. He is quoting almost $2,000 in repairs. If you go out the side wall you could put in a brand new stainless chimney for less money. Also you said you had 2 chimneys, the roof says you only have 1.


Some of these repairs need to be done no matter what. The top cover/crown is rusted and needs repaired and the caps need to be replaced. That's the majority of the almost 2k. I've debated about running the wood stove flue next to chimney with an external flue, but it's easily seen from the neighborhood and not sure I want to do that.

It looks like there is only one flue in these pictures, but there is actually two.

I'm just trying to evaluate if the entire flue should be replaced, or if I can get away with replacing the top 3 or 6 feet like the inspector suggested. If it's a triple wall and the rest of the flue is in good shape, any reason I shouldn't just use it?
 
That's the majority of the almost 2k.
That is way to high get other quotes.
I'm just trying to evaluate if the entire flue should be replaced, or if I can get away with replacing the top 3 or 6 feet like the inspector suggested. If it's a triple wall and the rest of the flue is in good shape, any reason I shouldn't just use it?
Yes the top sections obviously deteriorated and someone replaced them with galvanized. or the inner layer is gone and what we are seeing is the outer layer. Either way the rest of the chimney will be shot it all will need replaced.
 
That is way to high get other quotes.

Yes the top sections obviously deteriorated and someone replaced them with galvanized. or the inner layer is gone and what we are seeing is the outer layer. Either way the rest of the chimney will be shot it all will need replaced.

Ok - thanks! If I install a class A flue, do I need to have it insulated as well? Pretty sure the answer is no, but want to confirm. I feel like when I talk to people I get different answers (on all types of chimney topics) so want to know for sure.

Also, I can't vent both oil and wood burning in one flue right? Hence why I was asking about power venting the oil furnace/water heater.
 
Also, I can't vent both oil and wood burning in one flue right?
Correct, you cannot.
I'd get rid of that oil water heater...they are so inefficient...go electric.
Oh, and that used furnace that you looked at is no kind of deal...you can buy a new Drolet Tundra for that...a much cleaner burning unit. Or for a bit more $, the larger Drolet Heatpro, better if you have a high heatload.
Just throwing this out there, have you considered putting in a HE gas or LP furnace so to free up the flue for the wood furnace?
I wish I had thought of doing that instead of installing a "one flue" wood/oil combo furnace
 
Ok - thanks! If I install a class A flue, do I need to have it insulated as well?
Have what insulated? The flue will be insulated if it is class a. the chase Can be insulated or not there are lots of different thoughts on that. I think insulating the chase is a good idea but others do not.
 
Have what insulated? The flue will be insulated if it is class a. the chase Can be insulated or not there are lots of different thoughts on that. I think insulating the chase is a good idea but others do not.

Ok, thanks.

Correct, you cannot.
I'd get rid of that oil water heater...they are so inefficient...go electric.
Oh, and that used furnace that you looked at is no kind of deal...you can buy a new Drolet Tundra for that...a much cleaner burning unit. Or for a bit more $, the larger Drolet Heatpro, better if you have a high heatload.
Just throwing this out there, have you considered putting in a HE gas or LP furnace so to free up the flue for the wood furnace?
I wish I had thought of doing that instead of installing a "one flue" wood/oil combo furnace

I've been thinking about that. I'd like to get one of the tankless water heaters, but have heard the electric ones are not that efficient (probably better than what I have now though) and if I go with propane....I'll have to rent/buy a tank as I currently only have an oil tank. I am starting to think about overhauling the entire system and going propane furnace with a tankless water heater and then I can use my stack for an add on wood furnace. The only problem with that is......this entire project started with replacing my zero clearance firebox upstairs with a wood burning insert. A small project now has me thinking about replacing my entire heating system and spending $10k-$15k. What happened......
 
A small project now has me thinking about replacing my entire heating system and spending $10k-$15k. What happened......
Hehehe, welcome to home ownership! ;lol ;hm
 
The company we had wanted us to purchase a tank of LP a year, or we would get hit with non usage fees. Besides paying the yearly fees, because we didn't use much gas, the cost of fuel was inflated because we were locked into a contract. Late summer last year, we purchased a new LP tank. No more fees, inflated pricing, threats, etc. We have a LP dryer, 5 burner oven and furnace. From August of last year to now, it's cost us $40.00 (10% of the tank) to dry a load or two of clothes a day, and to cook and bake.

Our home had an oil furnace initially. My father tore out the oil furnace, put in a 90% efficient LP furnace which vented out the side of the house, changed to an electric water heater and used the chimney for an add-on woodfurnace.
 
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The company we had wanted us to purchase a tank of LP a year, or we would get hit with non usage fees. Besides paying the yearly fees, because we didn't use much gas, the cost of fuel was inflated because we were locked into a contract. Late summer last year, we purchased a new LP tank. No more fees, inflated pricing, threats, etc. We have a LP dryer, 5 burner oven and furnace. From August of last year to now, it's cost us $40.00 (10% of the tank) to dry a load or two of clothes a day, and to cook and bake.

Our home had an oil furnace initially. My father tore out the oil furnace, put in a 90% efficient LP furnace which vented out the side of the house, changed to an electric water heater and used the chimney for an add-on woodfurnace.

So am I understanding this correctly that the tank cost you 400? I'm starting to wonder if I should go this route. Just wondering if it'll cost me quite a bit to purchase a new LP furnace, purchase a LP tank, and have someone install.
 
So am I understanding this correctly that the tank cost you 400? I'm starting to wonder if I should go this route. Just wondering if it'll cost me quite a bit to purchase a new LP furnace, purchase a LP tank, and have someone install.
No, the fuel for the tank was $400 @ $.99 a gallon. The tank was $1200 new with 2 regulators and installation (500 gallon tank). I looked into a refurbished tank, but it would have costed me $900 and I would've needed to haul and install, with no warranty. With the non usage fees at $100+ a year and the price of gas costing me at least double, buying a tank paid for itself.
 
@bbauer161 check into www.thriftypropane.com. It's where I got tank and filled it at$.63 gallon on the first fill(market price minus $.07 discount at the time).
Hmm, interesting. I will have to pass this on to my inlaws...they are using a local company...I think they said they got the "new customer" rate last time (new house...well, old house...old and drafty) and it was still ~$1.25 gall. Looks like it would have been much less here. I was reading their testimonials...everybody was saying that they use less fuel now? And it burns cleaner/hotter or something? Is all LP not created equal?
 
Hmm, interesting. I will have to pass this on to my inlaws...they are using a local company...I think they said they got the "new customer" rate last time (new house...well, old house...old and drafty) and it was still ~$1.25 gall. Looks like it would have been much less here. I was reading their testimonials...everybody was saying that they use less fuel now? And it burns cleaner/hotter or something? Is all LP not created equal?
Not sure about LP usage since this is my first year in this house, not much data to compare too. I guess there are different grades of LP just like gasoline. Not sure if this is a marketing tool or not.

FWIW I think the refurbished tank comes with a 10 year warranty.
 
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