Propane gas vent pipe questions

  • 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.

mainecabin

New Member
Aug 31, 2022
5
Maine
I have some questions about venting for a Jotul Allagash BV 300 propane stove. It requires a type B 4” vent pipe.

I am locating the stove where there used to be a wood stove with a 7” pipe which I have removed. The stove will go in a 1 story room. The B vent pipe will be vertical and it exceeds all safety clearances. There is a about a 10 foot run to get to the large, pre-existing, boxed in, double walled galvanized steel firewall (this extends another 3 feet or so above the firewall to the top of the old wood stove termination cap). The firewall has a 7” round opening in the firewall. The attached picture shows firewall/ cap.

Do I terminate the B vent pipe at the top of the firewall by getting various vertical B vent pipes and/ or adjustable length B vent pipe to exactly match the height from the top of the wood stove to the firewall? I would need to get a type B 4” adapter to connect to the existing 7” wood stove pipe. Would that adapter be specifically for a B vent installation?

The other option would be to run the B vent pipe inside the old stove pipe and extend it above the firewall as I could run the B vent pipe inside the old 7” diameter above the firewall as there is plenty of room.

Can I use the current termination cap (chimney cap) which was used for the wood stove? It appears to meet all specs in terms of clearances. Thanks.

IMG_5395.JPG
 

mainecabin

New Member
Aug 31, 2022
5
Maine
The stove manual does not address a scenario of using an existing vent cap for the B vent exhaust but I am within the limits of all other B vent safety guidelines
 

mainecabin

New Member
Aug 31, 2022
5
Maine
Yes, you are right. I could put a B vent cap inside the cap you see in the picture. I didn’t think that would accomplish anything in terms of venting but maybe it is a good idea.