Suggestions needed to feed a rigid tube liner above the roof with a flat concrete top.

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yonny33

Member
Feb 9, 2021
120
Uruguay
Thinking about it more I think a ventilation hole in the wall between the bedroom and staircase for better circulation isn't a bad idea even if it's just to reduce the stagnant air in there that produces the small spots of mould in the corners in winter.
I have a spare extractor fan, make the perforation and try. Brick work gets messy though and double brick walls are always hard to work with. Can always cement it back up.
 

gthomas785

Feeling the Heat
Feb 8, 2020
442
Central MA
Begreen has been hinting at this, but I'll say it - It's always easier to move cold air away from a cold room than to try to move warm air in.

Rather than trying to capture heated air from around the stove and put it somewhere, think of ways to remove cold air from the bedroom and bring it closer to the stove.

So I might suggest putting a grille lower down on that staircase wall, to act as a "drain" for the cold air from the floor of the bedroom. If the aesthetics of that will be a problem, then you'd need to put in some more concealed ductwork inside the walls which is a bigger project.
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
Begreen has been hinting at this, but I'll say it - It's always easier to move cold air away from a cold room than to try to move warm air in.

Rather than trying to capture heated air from around the stove and put it somewhere, think of ways to remove cold air from the bedroom and bring it closer to the stove.

So I might suggest putting a grille lower down on that staircase wall, to act as a "drain" for the cold air from the floor of the bedroom. If the aesthetics of that will be a problem, then you'd need to put in some more concealed ductwork inside the walls which is a bigger project.
Yes I have read of this before. But some have complained of cold drafts coming into the warmer areas which concerns me, hence the idea of sucking in that hot air from the ceiling.

I think even with a grill nearer the floor of the bedroom will still be in contact with hot air rising on the other side, so in a way I could try the fan both ways.

One other point is that we often have the small window open in the en-suite with the door closed a few hours during the day. With the fan blowing out the cold air this is likely to draw in cold air from the bathroom I suspect as it's the closest opening.
 

gthomas785

Feeling the Heat
Feb 8, 2020
442
Central MA
Yes I have read of this before. But some have complained of cold drafts coming into the warmer areas which concerns me, hence the idea of sucking in that hot air from the ceiling.

I think even with a grill nearer the floor of the bedroom will still be in contact with hot air rising on the other side, so in a way I could try the fan both ways.
The beauty of this approach is that the cold air mixes with warmer air as it makes its way toward the stove. Yes, you may have a cold breeze coming through the vent into the stairway but there will also be warm air making its way up. I don't think you'll have the "cold wind" effect unless you forget to close the windows.

And, the effect will only be worst for the first few hours. Once the upstairs room gets warmer, the drafts will settle down.
 

yonny33

Member
Feb 9, 2021
120
Uruguay
The beauty of this approach is that the cold air mixes with warmer air as it makes its way toward the stove. Yes, you may have a cold breeze coming through the vent into the stairway but there will also be warm air making its way up. I don't think you'll have the "cold wind" effect unless you forget to close the windows.

And, the effect will only be worst for the first few hours. Once the upstairs room gets warmer, the drafts will settle down.
OK sounds like a solid plan. The extractor fan near the floor of the bedroom blowing out into the large staircase atrium. This will in turn bring in warmer air from the landing area, improve circulation and bring in drier air without having to open windows on cold winter days. Obviously, on a nice sunny day, we try to open up as much as possible as we experience cold but very humid winters here.

Thanks so much for your advice
 
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begreen

Mooderator
Staff member
Nov 18, 2005
88,240
South Puget Sound, WA
For testing, if the beach house is not far away, maybe just borrow one from there?
 

yonny33

Member
Feb 9, 2021
120
Uruguay
One obstacle I did hit and probably my biggest mistake (heart stopped when I realized) but could also be a positive thing.
When I fit the liner up the flue before the stove arrived I had the overlapping sections fit so they slipped inside one another flowing downwards. So any loose soot would fall all the way down and not out through the overlapping sections if that makes sense.

Well, the stovepipe had the opposite fitting, basically trying to fit a male to male part.
I had an extra 25cms of thick 2mm black stove pipe to play with so the easy option is to cut the 25cm off and use the stovepipe section without the narrower slip part that slips inside. Basically like a sleeve.
The straight pipe will slip directly onto the flue liner - female to male part in a way.

I believe the European version of my stove is opposite to other versions that I looked at.

just saw this today:

"
Please note, European stoves feature a male spigot as an outlet collar and require an additional Continental Stove Adapter or Double Socket Adaptor in the relevant diameter to connect standard single wall stove pipes.
"

oh yes also got a blast from a UK tradesman saying the boarding I used for the surround is completely unsuitable and not compliant with HETAS. Well he was following UK regulations but these boards are made only here in South America and comply to Clase Re2. Fire and heat resistant. It's not an open fireplace. They get quite warm to the touch but nothing to start a fire.
The company shows a display with a blowtorch directly on it and not igniting, also with a hand on the other side showing its heat resistance. Every country has their own codes and materials.

Do I possibly need to add some stainless steel backing plates behind on both sides to be on the safe side?
 
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gthomas785

Feeling the Heat
Feb 8, 2020
442
Central MA
One obstacle I did hit and probably my biggest mistake (heart stopped when I realized) but could also be a positive thing.
When I fit the liner up the flue before the stove arrived I had the overlapping sections fit so they slipped inside one another flowing downwards. So any loose soot would fall all the way down and not out through the overlapping sections if that makes sense.

Well, the stovepipe had the opposite fitting, basically trying to fit a male to male part.
I had an extra 25cms of thick 2mm black stove pipe to play with so the easy option is to cut the 25cm off and use the stovepipe section without the narrower slip part that slips inside. Basically like a sleeve.
The straight pipe will slip directly onto the flue liner - female to male part in a way.

I believe the European version of my stove is opposite to other versions that I looked at.

just saw this today:

"
Please note, European stoves feature a male spigot as an outlet collar and require an additional Continental Stove Adapter or Double Socket Adaptor in the relevant diameter to connect standard single wall stove pipes.
"

oh yes also got a blast from a UK tradesman saying the boarding I used for the surround is completely unsuitable and not compliant with HETAS. Well he was following UK regulations but these boards are made only here in South America and comply to Clase Re2. Fire and heat resistant. It's not an open fireplace. They get quite warm to the touch but nothing to start a fire.
The company shows a display with a blowtorch directly on it and not igniting, also with a hand on the other side showing its heat resistance. Every country has their own codes and materials.

Do I possibly need to add some stainless steel backing plates behind on both sides to be on the safe side?
Yes, it seems to be the convention in Europe that the male end points up. No idea why. What you have done seems like a common and acceptable workaround.
I once installed a tiny Swedish stove in my aunt's cabin that had a really bizarre outlet size. Somewhere between 4" and 4.5". I ended up using a stainless automotive exhaust reducer to get a tight fit on the pipe and stove.
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
In regards to venting the cold air out of the bedroom, I am completely on board with this and ready to install the fan.

But the wife thinks I am nuts and it's a crazy idea and will not work. How is the hot air going to enter the bedroom by blowing cold air out?? ..it won't come back to the bedroom and so on. hmm, the concept won't sink in. If she hears it from a 'pro' in the field she'll most likely accept the concept better.

Well if it doesn't work then I'll need to cement up the hole in the wall. LOL

I think the bedroom needs better circulation from other areas anyway without having to open a window in the cold weather.
 

gthomas785

Feeling the Heat
Feb 8, 2020
442
Central MA
In regards to venting the cold air out of the bedroom, I am completely on board with this and ready to install the fan.

But the wife thinks I am nuts and it's a crazy idea and will not work. How is the hot air going to enter the bedroom by blowing cold air out?? ..it won't come back to the bedroom and so on. hmm, the concept won't sink in. If she hears it from a 'pro' in the field she'll most likely accept the concept better.

Well if it doesn't work then I'll need to cement up the hole in the wall. LOL

I think the bedroom needs better circulation from other areas anyway without having to open a window in the cold weather.
There is a doorway to the bedroom, right? Which is connected to a hallway, and the hallway is open to the stairs. Or something like that.
That is how the warm air will get into the bedroom. The total volume of air in the room has to stay constant, so by letting / blowing the cold air out of the room, you are creating space for the warm air to enter from the hallway.
 

begreen

Mooderator
Staff member
Nov 18, 2005
88,240
South Puget Sound, WA
Pushing air out of the room creates negative pressure (vacuum) in the room. Cold air is denser than warm air, so by pushing it out down low from the room the displaced air has to be replaced with lighter, warmer air up at the top of the door. Tape a 12" strip of toilet paper to the top of the door frame to provide a visual cue.

The beauty of this test is that no holes have to be cut for proof of concept. Measure the hallway and bedroom temps before starting.
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
Looking at 2 fans, 10cm fan or 15cm fan.

One pushes 130m3 per hour, other 320m3 per hour. But think the 15cm is a bit wide to make a hole that big.

Room is 3.40 x 4.00 x 2.40 high 32.64 m3 plus the aisle.
the smaller one is fine I think.
draft at the bottom of the stairs with the stove on (no fan creating negative pressure in the bedroom)

1622772072607.png

Thanks
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
Gone for the smaller fan. Should change the volume 3-4 times an hour. Arrives tomorrow so ready for the weekend. If it's too weak I need a replacement for the guest bathroom downstairs anyway.
 

yonny33

Member
Feb 9, 2021
120
Uruguay
yep so the fan is coming today - we'll see my wife's reaction when I start making a hole in the bedroom wall! Maybe send her shopping.

For me makes total sense to bring in that air that as we can clearly see going up the stairs but not quite reaching this bedroom.
 

moresnow

Minister of Fire
Jan 13, 2015
1,701
Iowa
I have a 1 foot square floor vent in my stove room ceiling that passes directly up to my bedroom. This vent is approximately 12+ feet away from the stove location horizontally.
I have experienced very mixed results trying to encourage heat from the stove room up through this vent into the bedroom. I have used a 12 inch fan blowing both directions in the floor vent opening.
Generally speaking I have concluded that leaving my staircase leading up to the bedroom as well as the bedroom door wide open and forgetting about the fan in the floor vent opening is as efficient and effective as anything.
The only issue I have is that the hot air will rise through the hall/stairwell into the bedroom and force cool bedroom air down through the floor vent onto my end of the couch:eek: Somewhat unpleasant draft when it's very cold outdoors! When it bothers me I simply run upstairs and cover the floor vent until bedtime.

Fill us in on how things work out.
 

yonny33

Member
Feb 9, 2021
120
Uruguay
I have a 1 foot square floor vent in my stove room ceiling that passes directly up to my bedroom. This vent is approximately 12+ feet away from the stove location horizontally.
I have experienced very mixed results trying to encourage heat from the stove room up through this vent into the bedroom. I have used a 12 inch fan blowing both directions in the floor vent opening.
Generally speaking I have concluded that leaving my staircase leading up to the bedroom as well as the bedroom door wide open and forgetting about the fan in the floor vent opening is as efficient and effective as anything.
The only issue I have is that the hot air will rise through the hall/stairwell into the bedroom and force cool bedroom air down through the floor vent onto my end of the couch:eek: Somewhat unpleasant draft when it's very cold outdoors! When it bothers me I simply run upstairs and cover the floor vent until bedtime.

Fill us in on how things work out.
hmm that's not encouraging especially with a 12 inch fan.
Thanks for letting me know about your results.
As mentioned previously by begreen, thinking the negative pressure cause by the fan blowing cold air out will bring in the warm air. Had high hopes this would be effective.

Yes also heard about people feeling the cold drafts from blowing out the cold air. Might end up with that result near the sofa. (the end where my wife always sits). I'll end up in big trouble.

Could always reverse the fan if that happens to suck in the hot air from the staircase atrium so the cold air has further to travel and will hopefully have less impact when it falls down the stairs.
 

Shrewboy

New Member
Oct 15, 2020
55
Eastern Pennsylvania
hmm that's not encouraging especially with a 12 inch fan.
Thanks for letting me know about your results.
As mentioned previously by begreen, thinking the negative pressure cause by the fan blowing cold air out will bring in the warm air. Had high hopes this would be effective.

Yes also heard about people feeling the cold drafts from blowing out the cold air. Might end up with that result near the sofa. (the end where my wife always sits). I'll end up in big trouble.

Could always reverse the fan if that happens to suck in the hot air from the staircase atrium so the cold air has further to travel and will hopefully have less impact when it falls down the stairs.
Great work on this project so far! I enjoyed looking at the progress pics and stuff.

How big is your house, and how often do you plan to burn?
One thing to remember about cold drafts from pushing cold air around, once the stove has been hot for an hour or two there won't be much freezing cold air left in the house as everything equalizes, thats what happens in my 1200 square foot home, after awhile everything evens out
 

yonny33

Member
Feb 9, 2021
120
Uruguay
Great work on this project so far! I enjoyed looking at the progress pics and stuff.

How big is your house, and how often do you plan to burn?
One thing to remember about cold drafts from pushing cold air around, once the stove has been hot for an hour or two there won't be much freezing cold air left in the house as everything equalizes, thats what happens in my 1200 square foot home, after awhile everything evens out
About 1000-1100 square feet.
From now until the end of winter (Sep ish) we tend to light the burner every day usually later in the afternoon 4/5ish unless we have a very cold day so earlier on some days.

Living room gets up to a nice 24c with minimal loading of wood. (75F).

Also power on the underfloor heating a bit for additional heating. Nice to have a warm floor. Much less now with the new stove so will save on electricity bills.

On the ground floor, we have 4 big floor-to-ceiling sliding doors (2mx2m) but no double glazing so a lot of heat is lost through the glass, unfortunately. The cost to change all of those is huge.

I guess if we are pushing cold air down we may need to light up earlier

Still my instinct is to blow hot air into the room than cold air out
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
Fan installed. Wall wasn't too thick. Bricks quite soft so fairly easy. Fan's a bit noisy unfortunately (32dbl We'll see how it works for a while. Maybe pay more for a quieter fan later if we notice a difference when it gets colder again.

Wife hasn't seen it yet.

Can't seem to attach photos from my phone. Will try later on my pc

photo_2021-06-05_16-27-53.jpg photo_2021-06-05_16-28-49.jpg
 
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clancey

Minister of Fire
Feb 26, 2021
1,018
Colorado
Enjoying the thread and I have not lite my stove just yet and got french doors for this reason to encourage the hot air to blow through the whole house and I sure hopes this works when in the coldest part of the wintertime.. I have such a small house compared to yours because your trying to force it into your bedroom upstairs and I sure do not blame you--hoping it works out real well for you and will be keeping a eye on the thread for it is interesting.. clancey
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
Well, yesterday I tried the fan blowing cold air out and didn't see any change in temp really. (maybe because the hot air has too far to travel and fills up the other areas first).

Today I reversed the fan to blow the warm air directly from the staircase into the bedroom.

At 5pm my thermometer on my bedside table measured 19-19.5c.

10:50pm now and it measures 21.5c. So an improvement.

I have another fan that is only 2.5w and much quieter. One of those desktop USB fans (5v).
Tbh there isn't much difference in airflow between the 2 if the duct is short. Maybe 15% difference.

If I can get that small fan adapted and in the hole in the wall I can run it much longer and will disturb us less due to its super-quiet operation.

I'll experiment and see if I can get it in the 100mm hole.

The air coming out through the fan from the staircase measures 23c.
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
More realistically the room is keeping at around 20c with the fan blowing most of the day switching off when I go to bed.
Feels more comfortable at least.

Still wish I could vent some of the really hot air from the stove straight up but due to the limited space down the flue just doesn't look possible unless I have it coming out of the side and up the staircase but that will not look so aesthetically pleasing.

I've reversed the fan again to cold air out to see what happens if I leave it on all day like yesterday.
 

yonny33

Member
Feb 9, 2021
120
Uruguay
After a few days of testing certainly worth running this fan blowing the warmer air in from the staircase.
Keeping the room just a little warmer. Just comfortable and helps to circulate the stagnant air that gets stuck in this corner of the house without opening the windows.

I'll eventually swap the fan for the 8w soler&palau quieter one with the nice front plate.

Wife not so keen on spending 100 USD on a fan though (well I'm not either).

But it does come with a 5 yr warranty. But seen mixed reviews about the actual noise level of this. States 26dbA but some measured it at a much higher level.
26dbA at what distance though? Some brands state the distance at 3 meters. hmmm

Last cheap fan in the downstairs service bathroom lasted just 6 months.