Connecting chimney of rocket mass heater in basement with existing wood stove on ground floor

I'm renovating my basement and hoping to build a rocket mass heater. It will be located directly underneath an EPA wood stove located on the first floor (see attached). I understand that it is important to have the rocket mass stove chimney go all the way to the roof. Since I already have a chimney going through the roof at the same location, I was wondering if I could connect the chimney pipe of the rocket mass heater in the basement to the chimney of the wood stove. Is this a viable & safe idea? What are the risks? Any help would be greatly appreciated

Would you have both fires working ?

Rami Kayello wrote:I'm renovating my basement and hoping to build a rocket mass heater. It will be located directly underneath an EPA wood stove located on the first floor (see attached). I understand that it is important to have the rocket mass stove chimney go all the way to the roof. Since I already have a chimney going through the roof at the same location, I was wondering if I could connect the chimney pipe of the rocket mass heater in the basement to the chimney of the wood stove. Is this a viable & safe idea? What are the risks? Any help would be greatly appreciated

    Depends on the unknown airflow of your house, what are your basement windows like? And is the wood stove airtight? If it were my house, I would totally explore the idea, and give it a try.  

David Livingston wrote:Would you have both fires working ?

Yes, probably.

jonathan kedzierski wrote:Depends on the unknown airflow of your house, what are your basement windows like? And is the wood stove airtight? If it were my house, I would totally explore the idea, and give it a try.

There are two very small windows (2'x1' each). I don't really understand what you mean by airtight wood stove since it always needs air for the fire, though the chimney is airtight.

Thanks for the help everybody.

It is always considered a very bad idea, and prohibited by code, to connect two appliances to one chimney. Draft can be unreliable, and one may have a bad effect on the functioning of the other.

Glenn Herbert wrote:It is always considered a very bad idea, and prohibited by code, to connect two appliances to one chimney. Draft can be unreliable, and one may have a bad effect on the functioning of the other.

And in case something went very wrong. It could kill people in the house!

Just to remind what the consequences could be!

Glenn Herbert wrote:It is always considered a very bad idea, and prohibited by code, to connect two appliances to one chimney. Draft can be unreliable, and one may have a bad effect on the functioning of the other.

Not true, is done all the time. Think your typical gas furnace and water heater.
The catch is, there is a formula to figure the size of the flue that's needed. It uses known figures like BTU output, exaust temps, length or run, Ect... So if you can figure those out, it's totally possible to do and know if you can do it safely.

My own view is that this is a risky idea . Whilst it may be possible to connect up two gas appliances , a wood stove and RMH are both two huge variables to be playing with . Carbon monoxide is not a variable it kills - no smell taste or colour you are just dead