Oil Furnace and Wood Stove on Same Flue

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I used to have separate liners in my old house, but now i have a two into one setup. More creosote build up, but i ahe not changed it. Maybe someday.
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As with a lot of those "safety" codes, they address the "what if, worse-case"... they really don't do much to make us safer... they just protect the idiot from himself.
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A lot of the reason for the codes is that real estate can be bought and sold. I am amazed how stuff changes though In 1993 I needed an 8x12 flue min but apparently now you need six inch liner all the way up. It was in a fireplace with the stainless steel insert piece.

Post 1 doesn't state if the flue is lined or how high from thimble to top does it?
 
Can anyone tell me the odds of being injured or killed while cutting firewood versus the odds of being injured or killed by running two appliances in the same flue?? Anyone??

There are situations where you are actively involved and situations where you are passively involved. Burning wood is one where you are frequently passively involved. You cannot actively monitor anything while sleeping, or while away from the house. Because of that I tend toward following code, even if it does seem unlikely that I'll have any issues. There's no guarantee everything will be just fine but if the code is based on real problems, the odds are a little more in my favor if something goes wrong.

You, and only you, are responsible for you and your family. You, and only you, can make the call on this one. Do not let anyone else make this decision for you... not me, not anyone on this board, and certainly not government (although possible fines and whatnot, if there are any, should enter into the decision making). If you decide to use the existing set-up... well... don't be a fool, educate yourself on the possible problems, issues, dangers and how to minimize them. Keep a close eye on things (especially at first) until you get a "feel" for how the set-up performs, keep things properly maintained, and don't ever become complacent... don't ever become complacent about anything in life, the dangers don't begin and end with your chimney. And above all, never forget that you, and only you, are responsible for you and your family.

Exactly! Asking a forum why or why not as part of doing research is perfectly acceptable. Deciding it's ok "because the guys at the forum said so" is as bad as saying "I dunno why the building code says do this, but I'm going to do it."

There is a potential issue with inertia if the gasses in the stack don't want to increase velocity fast enough to prevent exhaust from the forced draft appliance to seek exit through the natural draft appliance (wood stove). Putting the wood stove fresh air intake outside the house would be worth considering.
 
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DavidBrown1212,

I have a similar flapper on my oil furnace and used to watch it flap around just from wind gusts when the oil furnace wasn't on.
I heat with just wood now but the oil furnace remains with it's flapper insulated over and the main disconnected on the oil furnace.
Although I love to heat with wood at some point in the future if I ever sell the place the people might not so the oil furnace stays.

On normal operation the flapper runs quite well on an oil furnace although I have seen giant smoke billows exit mine when the oil furnace backfired.
With a second fire source on the same line and a direct connection via T to that flapper it's just an invitation for fire to head that way.

Not saying it would ever happen and in reality probably very low odds of it, but if you burn firewood long enough who hasn't seen a backdraft happen even in a woodstove with a single direct chimney.
 
Whitespider,

Life is all about risk and reward.
I'm not saying he should run out and change the system for fear of it causing a fire, it's just not a good setup for a woodstove.
All about risk though and really it's very low risk.

Most people end up doing the duct tape repair now and then on something to get it working but long term repairs the duct tape usually gets put away.
Repairs on things that shoot fire up a house duct tape sorts or repairs seldom work properly.

For me it's something I would correct ASAP, worrying about that bad would have me putting in chimney pipe.
We all have risks in life but it's nice to make them as small a risks as possible.
 
There are situations where you are actively involved and situations where you are passively involved. Burning wood is one where you are frequently passively involved.

I don't agree with your analogy... I guess it's perspective and how you define the words.

When you fell a tree, you "actively" do the cutting, but once it starts falling you are only "passively" standing under it... you "actively" cause the action, but you have no input once it begins, you can only "passively" watch the result.
Wood burning may "allow" you to be "passive" at times of your choosing, but unlike the above example, you always have the option to become "active"... with wood burning you "actively" cause the action, and you have the option for input at any time during the result, including stopping the action.

You can be killed or injured while felling a tree because you are "passively" involved (you can't stop the action)... whereas you can save your life or property during a wood-fired appliance malfunction because you can be "actively" involved (to use a cliché, you can throw water on the fire).
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Some good news,
I have just been in contact with a family friend whom spent a lot of time in the house during the previous winters.
He said that both the wood stove and the oil furnace were both used together all winter. He also said that the flue has the capacity for both appliances and that he remembers that the only time that the wood stove was not being used was when it was full and needed to be cleaned out.
This at least puts my mind at ease for this year.

Thank you for all of the replies
 
We are moving to our house in Maine after the new year. The current set-up is, in the basement an oil heater and our Cawley 600 wood stove share the same flue. Upstairs we have an older insert with a blower. Although the set-up in the basement is "Grandfathered", I know that this is not an ideal. Since we are moving to the house during the winter I have some questions regarding safe burning practices. Being that the house is vacant, we turned the heat to 55 degrees to save on heating oil. When we arrive I will obviously turn the heat up to make the house comfortable. Since we have a stove in the basement and an insert upstairs, I would like to primarily heat with wood.

My questions are:

1. Can I use the wood stove while the heat is turned on?
2. Should I worry about using the stove and oil heater simultaneously being that they share a common flue?

Thanks for any suggestions,
Jason

The first thing you should do is evaluate the age of the chimney. Older chimneys can have loose bricks that can leak smoke and hot embers into walls or attic spaces, not to mention Co2 which can be deadly. You could burn your house to the ground or suffocate the first time you use your stove without taking your time and setting things up properly. I personally had a ceramic chimney in a house I owned and single wall stove pipe was inserted from the bottom of the chimney one length at a time and connected together with sheet metal screws. I was lucky in my case because I could ad sections because my chimney was anchored between floor joists i the basement. This was my only source of heat I used for many years.
You can do the same thing by adding another hole in your chimney directly across from your furnace so that you can remove the furnace vent temporarily to access the sheet metal elbow of the new chimney to drop in a flexible chimney liner from the roof or single wall pipe from the roof. I've never dropped in single wall piping from the roof connected together which could be very difficult but you could try chimney liner that comes in 25-30 foot lengths that could attach easily to the stove outlet pipe. Whatever you use you need to buy a chimney cap to keep rain out and to secure the other end of the liner. Just a little work to make it all worthwhile
 
The first thing you should do is evaluate the age of the chimney. Older chimneys can have loose bricks that can leak smoke and hot embers into walls or attic spaces, not to mention Co2 which can be deadly. You could burn your house to the ground or suffocate the first time you use your stove without taking your time and setting things up properly. I personally had a ceramic chimney in a house I owned and single wall stove pipe was inserted from the bottom of the chimney one length at a time and connected together with sheet metal screws. I was lucky in my case because I could ad sections because my chimney was anchored between floor joists i the basement. This was my only source of heat I used for many years.
You can do the same thing by adding another hole in your chimney directly across from your furnace so that you can remove the furnace vent temporarily to access the sheet metal elbow of the new chimney to drop in a flexible chimney liner from the roof or single wall pipe from the roof. I've never dropped in single wall piping from the roof connected together which could be very difficult but you could try chimney liner that comes in 25-30 foot lengths that could attach easily to the stove outlet pipe. Whatever you use you need to buy a chimney cap to keep rain out and to secure the other end of the liner. Just a little work to make it all worthwhile
really?? a three year old post???? know how many past members are no longer here???? :dizzy::dizzy::laughing:
 
In case anyone is still interested, you used to be able to install an oil appliance and a wood burning appliance on the same floor into the same chimney flue as long as the oil vent was above the wood.
Now each appliance requires its own flue.
 
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