converting from wood to gas - vent question

  • 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.

steve113

New Member
Mar 26, 2011
3
Eastern MA
Hello,

We had a wood stove insert in an existing fireplace. This fireplace had a brick chimney that was falling away frm the house so was replaced with a class A 6" stovepipe with a wood chase built around it about 5 years ago. (chimney was on exterior wall) Worked great for the wood stove set up.

We've decided to switch from wood to gas. Main reasons are we need a faster source of heat for the room and less work involved now that we have kids and a busier schedule. I sold the insert a few weeks ago and now are on to selection agas unit.

The problem we're running into is we're told the 6" stove pipe is not big enough to run the 2 3" vents for direct vent gas stove. The local fireplace store had no other options for us as they only sell direct venting units.

I have been told a B vent may work but also know they are not as efficient.

Does anyone have a recommendation? We are open to having a gas stove on the hearth instead of an insert. I don't want to pull out the stove pipe or chase but find something that works using it. It was expensive to have installed/repaired so we'd like to salvage it for the gas venting. Plus a future homeowner would have the option of converting back to wood if they so chose.

Open to suggestions.

thanks!
 
If you're locked into a gas insert you may be SOL, but if you can use a DV stove,
you just might be able to run a single 4" exhaust up inside your liner
& use the space remaining in the SS liner for the combustion air.
The trick will be connecting the DV to the liner with the adapter kits that
are available on the market.
There are masonry adapters & Class A adapters & one of them may be possible to
use SAFELY in your situation. This will be a pro install & NOT a DIYer...
 
thanks - will talk to the retail store about stoves they have that may work. I was looking at the Hearthstone Stowe DV so want to see if they can set that up to work. Definitely not doing this project ourselves. Plan on paying a pro for the work - need to pass all inspections and have this vented correctly.

Thanks!
 
Many direct vent inserts are approved for a "stubby" intake liner as well. The intake could be slightly ovalized just as it enters the 6" Class A and then end. It will draw air down the old flue around the 3" exhaust liner. Just needs to be sealed up well top and bottom so it does not draw room air.
 
Hi Steve, I am a licenced Gasfitter and NFI certified installer on Cape Cod and could certainly help you out if need be. Matt 508 775 7593
 
If the 6" wood chimney is a straight shot without any offsets, the 2 3"liners will go down with some patients.
 
Install fire 1 said:
If the 6" wood chimney is a straight shot without any offsets, the 2 3"liners will go down with some patients.

Not if they are patients from a mental hospital. Those guys have no patience.
On a short run, we have done it. pull em both thru at the same time, nice and slow
 
Hi all,

thanks for the feedback. So far I have vistited one store that primarily carries DV. They only had one DV stove from Hearthstone that was tested for using the class A pipe with the 4" inside it (I believe called co-axial). According to this dealer this can only be done and approved if the stove was specifically tested and approved in the state of Mass. They do have a natural vent Hearthstone stove (B vent) that would work but I don't like the style a whole lot plus want a DV if we can do that.

I would love to fit the 3" intake and outtake vents into the 6" but this particular store said it could not be done. If it can be done I would get what we originally wanted (gas insert) and be home free. I'll be visiting another store this weekend to look at a Jotul (GF 300 Allagash)stove that comes in both the BV and DV.

thanks
Steve
 
If you want to see if it will fit, go buy some cheap 3" dryer vent, duct tape them together, rig up a pulling system and try to get them down the chimney
 
steve113 said:
Hello,

We had a wood stove insert in an existing fireplace. This fireplace had a brick chimney that was falling away frm the house so was replaced with a class A 6" stovepipe with a wood chase built around it about 5 years ago. (chimney was on exterior wall) Worked great for the wood stove set up.

We've decided to switch from wood to gas. Main reasons are we need a faster source of heat for the room and less work involved now that we have kids and a busier schedule. I sold the insert a few weeks ago and now are on to selection agas unit.

The problem we're running into is we're told the 6" stove pipe is not big enough to run the 2 3" vents for direct vent gas stove. The local fireplace store had no other options for us as they only sell direct venting units.

I have been told a B vent may work but also know they are not as efficient.

Does anyone have a recommendation? We are open to having a gas stove on the hearth instead of an insert. I don't want to pull out the stove pipe or chase but find something that works using it. It was expensive to have installed/repaired so we'd like to salvage it for the gas venting. Plus a future homeowner would have the option of converting back to wood if they so chose.

Open to suggestions.

thanks!

There are a few gas inserts that are approved to just stub the intake.

Brad
 
Status
Not open for further replies.