Replaced fireplace with wood stove - help please

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Fekish

New Member
Jun 10, 2023
3
Greece
Hello!

We recently took down a fireplace, but we want to use the exterior double 200mm / 250mm pipes, and connect them indoors with single pipes/angles to connect the 150mm stove which is also 97cm of height.

There are two issues that we have:
1. The outdoor pipe is installed with a 45° angle to go through the exterior, which although seems ok since 90 degrees are avoided, i don't know how to connect it now to cover the hole on the wall inside.
2. The wall is too low, and there will not be a long pipe directly above the stove. The existing hole of at around 150-160cm from the floor.

So my questions:
- would you leave everything at 45° angles, and have a very small pipe directly of the stove, maybe even 10cm-20cm?
- can we even directly connect a 45° degree connector directly to the stove, if there will be 3 indoor 45° and one 45° at the outside pipe?
- is it better to change the outdoor to indoor point and make it horizontal ( this it will look better on the inside wall) , so that the hole on the inside wall will be slightly higher , and then with a 90° angle to use a longer pipe directly above the stove. By longer i mean just max 30-40cm.

Am thinking the 45° in order to move away from both walls. The walls have been replaced with fire gypsum boards.

Any other ideas for the indoors pipes and how to connect to existing outdoor pipes?
Thanks

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Last edited:
Welcome. What stove is going in? Some stoves work well on shorter chimneys and are not that fussy about the draft.

One concern is preventing water entry through the wall. I'm concerned about the 45º pipe going through the wall could create an issue for leakage. Going though at a 90º would lessen this chance and would permit a tee outside to make cleaning easy. What is supporting the chimney pipe. Normally the 45º elbow wouldn't be carrying the weight, wall brackets or a tee would do that.

The house appears to be of non-combustible construction but it looks like there is a wood soffit with the exterior chimney pipe very close if not touching it. That is not allowed. In the US, chimney pipe requires about a 5cm gap between it and any combustible.

Is the interior gypsum board paper faced or bare? If paper-faced, there are clearance issues that need to be considered for the stove pipe and for the stove.
 
Welcome. What stove is going in? Some stoves work well on shorter chimneys and are not that fussy about the draft.

One concern is preventing water entry through the wall. I'm concerned about the 45º pipe going through the wall could create an issue for leakage. Going though at a 90º would lessen this chance and would permit a tee outside to make cleaning easy. What is supporting the chimney pipe. Normally the 45º elbow wouldn't be carrying the weight, wall brackets or a tee would do that.

The house appears to be of non-combustible construction but it looks like there is a wood soffit with the exterior chimney pipe very close if not touching it. That is not allowed. In the US, chimney pipe requires about a 5cm gap between it and any combustible.

Is the interior gypsum board paper faced or bare? If paper-faced, there are clearance issues that need to be considered for the stove pipe and for the stove.
thanks for your time!

I am actually in Europe, and the stove is a 14kw one.
The outdoor pipe , which is double sided, was like that for some years now for the fireplace, and at the top the wood was cut and was fixed i think with what seems as cement. Also is fixed by 2 other brackets onto the wall.
The house is indeed with bricks outside, and inside of gypsum, and above an attic with wooden beams.
At that corner we have installed now a fireresistant gypsumboard.

So the other issue that i didnt think of is the water leakage.



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Interesting setup, never seen a 45 through the wall before and agree with begreen that moisture is a major concern.
 
90 degree elbows reduce draft a bit, there's a rule of thumb for estimating their effect on overall chimney height, when morning reaches begreen's timezone I'm sure he'll remember it better than I. 45 degree elbows do the same, but to a lesser degree.

In both cases, the height of these elbows measured up from the stovetop or stove collar is important. A 90 degree elbow placed 10cm above the stove is going to behave more poorly than one located 100 cm above the stove.

If your chimney height is well over 5m, then all of this becomes much less important, as taller chimneys usually have less issues with developing good draft. If your chimney is at or below 5m, then you need to be more careful with number and placement of elbows, so as to not reduce the effective height below that recommended for your stove.
 
Great thank you guys!
I thought that no one answered, but in the end the notifications went to my junk email.

For the water, the pipes will be connected in such a way that if indeed there is some rain water, then it will just go in the stove.

Then because of the 45 degree angles everywhere, i think the smoke will not have issues going upwards, but i am thinking if there is a problem that it will be going too easy upwards... I will have around 1m above the stove of 150mm pipe, and the double walled 200mm pipe going up outdoors to the roof. .