Chimney Thimble Okay?

[eric1]

Hello all, I'm new here and newer to woodstoves. We are replacing an old cook stove in our living room that we never use and the previous owners used rarely. It will be replaced likely with a drolet 1800. The current setup is single wall 6" pipe from the stove up to the thimble where it adapts to 8" to dump into the chimney. I'd like to setup the new stove with insulated pipe to reduce heat transmission to the mantle above and TV( will be relocated further away). How would I go about making this connection from 6-8" with insulated pipe? I can't seem to find any adapter to allow that. Also curious if this is okay the way it seems to dump directly into the thimble here? Thanks for any help.


Photos of current setup as I was dismantling it.

 

[stoveliker]

It's best to add a 6" insulated liner to the chimney, and go 6" all the way. The drolet wants 6" anyway.

The double wall stove pipe inside before the thimble is not insulated, just double wall.

 

[eric1]

It's best to add a 6" insulated liner to the chimney, and go 6" all the way. The drolet wants 6" anyway.

The double wall stove pipe inside before the thimble is not insulated, just double wall.

Thanks for the input. I see what you mean about the double wall pipe now. Would be nice if it were insulated, but still beneficial with the clearance improvement I'd say. Do you know of an adapter that would work for 6" double wall into that thimble? And is it okay to just dump right into that thimble as it's been?( Hasn't burned the house down yet and it's all brick and block there but I don't know the details of that.

As for the chimney it's in good shape and I'm not going to be able to do the lining and new stove all at once so I need to get it setup as is for the time being. Hopefully lining will be able to be done next year.

 

[begreen]

What is the ID of the clay tile liner in the chimney?

 

[stoveliker]

Changing cross section area is going to affect draft. Some stoves will be fine with that, others less so.

I don't know enough about the thimble issue.

 

[eric1]

What is the ID of the clay tile liner in the chimney?

8x12" did not measure the inside when I cleaned them and replaced the caps. I'd imagine 6*10 inside or so..

Changing cross section area is going to affect draft. Some stoves will be fine with that, others less so.

I don't know enough about the thimble issue.

I will research this a bit more. The second chimney in the basement is setup similar to this with a modern regency stove and it burns well so I'm hoping it will be ok for this season.

 

[stoveliker]

If the stove wants to have 6" dia, that amounts to 28.25 square inches cross section.
The 6*10 is 60 square inch. That is so far.more that the gases will expand, this cool down, and slow down. This can create creosote accumulation. Especially if the chimney is not insulated.

If the regency is a 5200, it wants an 8" chimney (I think), which is 50 square inch. Much closer to the 6*10.

 

[eric1]

If the stove wants to have 6" dia, that amounts to 28.25 square inches cross section.
The 6*10 is 60 square inch. That is so far.more that the gases will expand, this cool down, and slow down. This can create creosote accumulation. Especially if the chimney is not insulated.

If the regency is a 5200, it wants an 8" chimney (I think), which is 50 square inch. Much closer to the 6*10.

The regency is on a 6" vent as well with the adapter to 8". Looking at your numbers I do see how there could be an issue there. While looking at the chimneys and pipes just now I also noticed that even though I have two flues out my chimney both of these stoves are piped into one. So it looks like I'm going to have to figure out breaking into the other flue in the end anyway to do a proper install for the new stove. This was a bit of a surprise.

 

[bholler]

The regency is on a 6" vent as well with the adapter to 8". Looking at your numbers I do see how there could be an issue there. While looking at the chimneys and pipes just now I also noticed that even though I have two flues out my chimney both of these stoves are piped into one. So it looks like I'm going to have to figure out breaking into the other flue in the end anyway to do a proper install for the new stove. This was a bit of a surprise.

Yeah you definitely can't use a 6" stove in an 8x12" well you can but it isn't going to work properly

 

[stoveliker]

If I understand correctly that you have two stoves into one (clay) flue, I have to advise to stop burning. This is dangerous. Forbidden for very good reasons. Back draft (Co poisoning) etc

 

[eric1]

If I understand correctly that you have two stoves into one (clay) flue, I have to advise to stop burning. This is dangerous. Forbidden for very good reasons. Back draft (Co poisoning) etc

Yep. The one has been capped and not been used by us. We were planning to install a new stove where the disused cook stove sits and pipe it in, hence my questions today. But looks like im now going to have to figure out how to drill into the other flue the chimney has and hook up there instead. Not sure why I have two flues but someone only hooked up to one of them. The joys of buying old houses.

 

[EbS-P]

Yep. The one has been capped and not been used by us. We were planning to install a new stove where the disused cook stove sits and pipe it in, hence my questions today. But looks like im now going to have to figure out how to drill into the other flue the chimney has and hook up there instead. Not sure why I have two flues but someone only hooked up to one of them. The joys of buying old houses.

I like the saying “if you can’t afford to do it right the first time you can’t afford to redo it.”

 

[begreen]

8x12" did not measure the inside when I cleaned them and replaced the caps. I'd imagine 6*10 inside or so..

That is 60 sq in area or a bit more. The stove is rated for 28 sq. in. so that is more than double the area and not recommended. The increase in size will slow the flue gases down a lot. Combined with a cold exterior chimney this may lead to creosote accumulating, especially near the top of the chimney.