Venting into an existing chimney

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
RPK1

RPK1

Member
Nov 24, 2008
57
Eastern CT
We are installing a Harmon pellet stove in my son's basement. There is a new masonry chimney with an 8x8 flue that I would like to vent into. We could vent the stove out through the floor joists but the joists are running in the wrong direction and it would be more difficult to deal with. There may be clearance issues trying to get through the wooden perimeter and the floor joists. The masonry chimney is approx 36' tall and is located totally inside the house and an unheated attic. So it stays reasonably warm. I also will be installing the exterior make-up air kit. Any thoughts on this would be helpful.

Thanks, RPK
 
First of all, is the basement finished/insulated? Second, you ARE planning on installing a flue liner, correct?
 
The basement is not insualted. It is a 32'x20' area that is 9'ft high and totaly beneath the ground. I was on the fence with the flue liner seeing that it was an 8x8 flue with a clay liner.

RPK1
 
Others will chime in, but I believe all manufacturers require a 3 or 4" vent pipe per the manual, ergo you won't get a permit pass off if you don't install it.
 
In addition to having to use a liner, is the basement install absolutely necessary?

An uninsulated large basement will be VERY hard to heat (concrete soaks up all the heat). So the next question is, are you trying to heat the basement, or upstairs?
 
10-4 on the un-insulated basement being hard to heat. Much less getting heat upstairs. Before I moved my office out of our unfinished basement I would fire the wood stove down there around seven in the morning and the room temp didn't start showing it until around noon. The walls were eating the heat.

As to venting into the masonry chimney, it'll work fine with a liner. Might work fine without one. Heat has a silly habit of wanting to rise. If there is a problem then you could line it after the problem arises. Just keep an eye on that flue monthly.
 
We are moving the pellet stove from the first floor to the basement due to a new sun room addition that will have to eliminate the vent. The house has hydro-air so the plan is to have a sheet metal shop fabricate a hood system over the stove and have the air handler move the heated air throughout the first floor of the house through the existing duct work. There is no other option to relocate the stove on the first floor living space. If the lack of insulation in the basement is an issue I'll stud it up and finish it off.

My real issue is venting the stove into the existing masonry chimney. The Harmon manual shows a detail of the their stove venting into a masonry chimney. They state for normal operation a this is an excellent way to vent their stove. It will give better natural draft and vent out any smoke in case of a power failure. They state a liner may be required if the chimney is "questionable" (we have 8x8 clay tile). I don't see any code or safety issue here. I am just wondering if the stove will operate properly vented into this chimney.

Thanks for all of the help
RPK1
 
Hello

I have talked to others and venting into a masonry chimney is fine. I do it and just have a clay liner. Not sure about the codes but they do vary alot.

Also I do want to tell you about my experience in ducting the heat up. I used an 8" to 4" chimney reducer for the 4" pellet pipe.

I had a hood over the stove and did get 80 degrees F of heat up which is certainly better than nothing. However when I added to the ductwork and brought it down to the front of the stove where the heat comes out, I got 150 Degrees of heat upstairs!!! What a warm difference!! Also note the codes when ducting but there is no specific code on ducting warm air from a pellet stove!

See my post in this thread:
https://www.hearth.com/econtent/index.php/forums/viewthread/71518/
 

Attachments

  • PS3PelletStoveBackplane&connection 100sc.jpg
    PS3PelletStoveBackplane&connection 100sc.jpg
    30.6 KB · Views: 1,596
  • PS3PelletStoveBackPlane&Connection 270sc.jpg
    PS3PelletStoveBackPlane&Connection 270sc.jpg
    49 KB · Views: 527
  • PS3PelletStoveBackPlane&Connection 240sc.jpg
    PS3PelletStoveBackPlane&Connection 240sc.jpg
    31.4 KB · Views: 551
Thanks Don. Very helpfull information. I talked with the Fire Marshal this morning. I gave him a copy of the Harmon manual and he said there was no code issue.

RPK1
 
RPK1 said:
Thanks Don. Very helpfull information. I talked with the Fire Marshal this morning. I gave him a copy of the Harmon manual and he said there was no code issue.

RPK1
Click to expand...

Some people construe the codes and try to make you feel like you cannot do anything!!

That is very good news!!

Excellent, you are on your way, so let's see some pics when your done please?
 
Success in heating your home is having control of heat loss regardless of the heating system being use. I hope you continue with the option of insulating the walls. IMO, it is the only way to try to heat your home, not the state of CT. A word of caution. The exposed insulated wall cannot be paper backed insulation, plastic, or foam. There are several acceptable materials such as drywall and fire retardant coatings. I have my stove in a finished daylight basement. We are toasty warm on both levels and only use the furnace assist as a back up when temps fall to 15-20 F. It only runs a few minutes then. My proof of that working is that we have used less than 200 gallons of oil in one year for both our oil fired hot water heater and and our hot air furnace. we have a little over 2100 sq feet of floor space. My wife likes it 74-78F.
The only way I could have accomplished this is with insulation, an OAK for the stove, and keeping up with cleaning the stove and venting. My stove is nothing special, and my pellets are fairly good, but not the very best. We usually burn 5 tons, but last year burned 6. I'm home most of the time so I can keep an eye on how things are going.
 
Is there anything (device) that vents into the chimney?
 
No. The house was built five years ago. We put in a 8x8 stick chimney for future woodstove. My son decided on the pellet stove because he has no extra time to fool around with wood. I have the time to fool around with wood.

RPK1
 
Status
Not open for further replies.

Similar threads

R
Stainless pipe through floor joist question
Replies
2
Views
928
The Hearth Room - Wood Stoves and Fireplaces
racer765
R
J
Venting Enviro Mini in New Construction
Replies
5
Views
772
The Pellet Mill - Pellet and Multifuel Stoves
bogieb
bogieb
B
Class A chimney transition to existing masonry?
Replies
5
Views
513
The Hearth Room - Wood Stoves and Fireplaces
begreen
begreen
H
Wood stove question, Will venting sweat
Replies
13
Views
512
The Hearth Room - Wood Stoves and Fireplaces
begreen
begreen
S
Seeking advice regarding venting Harman P-43
Replies
3
Views
650
The Pellet Mill - Pellet and Multifuel Stoves
SciGuy
S
Top Bottom
Back