Updraft and wind noise problems with Chimney with stove

MSCMH

Hi all,

I am having serious noise problems with our chimneys due to updraft.
Now I have read loads of threads about downdraft and there si loads of products to prevent downdraft but the problems I have is with updraft.

I dont really understand why so many people have problems with downdraft. to me it seems obvious that when you are at a windy place (west coast, Donegal) and you have no Cowl that you would generally have, due to the venturi effect, an updraft problem rather that downdraft?

I have seen the cowl that can be closed via a chain for open fires however this is not suited for my stoves.

I am sure there must be others having the sdame issues and I am hoping they managed to solve it and would be so kind to share their solution with me

Thanks for reading
Cheers

A qiuck google found one of these http://www.kbf.ie/accessories

Anti Updraught Cowls

The Aerocowl
The AEROCOWL has been aerodynamically designed to maximise the flow of the wind to reduce overdraw or updraughts, which pulls the heat from the room up the chimney resulting in excessive fuel use and a "cold" room.

Independent tests indicate a minimum fuel saving of 15%, whilst some customers have seen savings of over 25% in the first year of use, giving a short payback time especially if you have a fire or stove lit throughout the Winter.

The AEROCOWL is made from stainless steel and is maintenance free.

MSCMH

Thanks for that.

I have found this one too but their official AEROCOWL website looked a bit dodgy and I wasnt sure if its any good.

Woule be very interesting to know what experiences that have been made with it.

Cheers

Trompette

Hi,

At least someone with the same problem I have...

I am living 100 m from the see Galway bay. My landlord installed a stove (insert) this summer (Thanks to him). I cant use the stove when it's windy.
A contractor changed the cowl for an anti-drawback but this is not good at all.

MSCMH, did you fix the problem? How?

Thanks

mp22

A temp solution is to let a large amount of ash build up it will help reduce the draft.

Trompette

It's what I do but all the ash is blow up at the top of the gills even closed.
But maybe the iron cast has some leaks and it's not closed enough.
Really it's like a forge when windy.

MSCMH

Trompette wrote: »

Hi,

At least someone with the same problem I have...

I am living 100 m from the see Galway bay. My landlord installed a stove (insert) this summer (Thanks to him). I cant use the stove when it's windy.
A contractor changed the cowl for an anti-drawback but this is not good at all.

MSCMH, did you fix the problem? How?

Thanks

Sorry for my late reply...

No the aerocowel didnt solve my updraft/noise problem at all. Expensive mistake...
The noise is different seems smoother, not as agressive but still way too much on windy days and the noise is almost unbearable for sleeping. Also way too much updraft for having an efficient fire in the stove.

Dont know what to do next. thinking of...

A: removing the stove :-(
B: installing H-cowel
C: cant do this easily as the wall are from 1820 but putting some kind of a closing mechanism in the flueliner just above the stove if its not used.

If anybody reads this and has similar problems or solutions please let me know!

Thanks

Trompette

Hi MSCMH,

Happy to read you even late because the problem is not fixed.

1- My landlord asked to the contractor to change the previous cowl by a "good" one. I was there when he did that. The cowl looks like this one, the 4th in the page.
http://www.sweepmychimney.ie/chimney_sweep_products_5.html
On the box was "anti-back-draft cowl", bad sign. In fact nothing really better. Back-draft is not up-draft !

2- I saw in McDonogh Galway (I am based in Galway area) a cowl with reduction like a Chinese hat with a small orifice at the top (truncated cone). The seller told me it is for solid fuel and anti-up-draft (~€75). I'd like to try it but my landlord is not ready yet...

3- A neighbour have this cowl, the last in the page
http://www.sweepmychimney.ie/chimney_sweep_products_5.html
He told me it is very handy but I didn't see his stove when windy. Moreover it needs a chain going in the chimney from the cap to the room. Not every install could have that.

4- Previously my house had an open fire. The chimney had a H at the top. I never had the opportunity to try it. Now this H cowl is in the back of the house as the chimney diameter changed for smaller. This is a stainless steel cowl, measures are, diameter 20.5 cm total high 85 cm. If the size is good for you and my landlord is OK, you could try it and maybe buy it if good. At least I'll know the effects and this could guide the next choice.
If the chimney opening has an internal diameter between 18.5 to 20 cm I think it could be good.

Hope this will help.

BlueM

Hello there,

I am having the same problem and wondered if you found a solution. The noise on a windy day is crazy and I can't control the burn in my stove due to the massive updraft. I would really appreciate any advise thanks.

Trompette

Hi BlueM,

My landlord asked a contractor to install the cowl (2) describe in my previous post.
This cowl reduce the diameter to limit updraft. See:
http://www.kbf.ie/accessories
Cowl:
8 to 4 Reducer
I think my cowl has a smaller output than in the picture.
Be careful, there are different sizes with the same shape, some are for solid fuel and other with smaller output diameter is for oil fuel.

So, I tried with my stove (insert) in a not too much windy days. I can say this is a big improvement.
I'll will keep this as I don't think I can do better.
The only problem is at the start of the fire. In the chimney, the space between the smaller stainless steel pipe and the big clay pipe is not filled with insulating material. I have to be careful to not open the stove door before the chimney become hot. If I open the door I will have smoke in the room. As soon the chimney is hot there is no problem but the time is longer.
If you can't find better, this is the only solution to improve.

Maybe you could have a look at this document I just found. I don't know this cowl.
search : actclean preventus cowl

www.act-clean.it/ documenti-1/ workshop-energia-5-novembre/ Chimney%20cowl%20for%20reduction%20of%20chimney%20draft.pdf

Hope this will help

BlueM

Thanks Trompette,

I have looked at this. A company call topcap recommended I get an anti updraft cap as I only have a problem on really windy days?

Did you have the problem all the time or just on windy days?

Let me know thanks

Caspero

Trompette wrote: »

Hi BlueM,

Cowl:
8 to 4 Reducer
I think my cowl has a smaller output than in the picture.
Be careful, there are different sizes with the same shape, some are for solid fuel and other with smaller output diameter is for oil fuel.

So, I tried with my stove (insert) in a not too much windy days. I can say this is a big improvement.

Hi Trompette,

Since you've been using the 8 to 4 reducer for over a year now, what was it like on very windy days? I have a similar issue and I'm looking into which cowl to use. Currently deciding between a H-Cowl and something like what you described.

If anyone else who has a anti-updraught cowl wants to share what it's like it would be great to hear from them.

Thanks!

BlueM

I would also love to know thanks

Trompette

Hi there,

Let me tell you what happened to my chimney from the begining:
When I came in the house, it was an open fire. A first contractor did some works and added a stainless steel tube inside the big pipe. Around 2 meters up from the inside, contractor did a cubic empty chamber (around 30x30x30cm) to connect the top pipe to the bottom pipe.
IMHO it was strange and not good.
Contractor added a anti-downdraught. (The problem is too much updraught, not the good cowl)
Result: Not good at all.

Another contractor changed the cowl to the one with reduction diameter.
Result: Better but very difficult to start the fire. When the pipe was cold, I had drawback. It was long to heat the pipe.

After a while a third contractor want and broked all the steel pipe and changed it to a clay reinforced pipe. This is not a usual clay because I could see composit in it. Each part is around 50 cm long assembled together with high temperature black compound. All put on a sturdy platform with a hole, the stainless steel bottom pipe directly connected to the up pipe (no cubic empty chamber). He added insulation between the large and small pipes.
On the top, the reduced cowl.
Result: A lot better, at least. Fire starts quick, no drawback. With low to good medium wind the chimney is good.

However last week we had a storm, 120 to 150 km/h wind, the insert stove is useless too much updraught. Just good to heat the outside! I didn't use it this week.
We have to take things into consideration: The pipe is the state of the art, can't be better. The cowl is the best I found. But the insert stove a first price, air admission is difficult the set, heat can't escape to the room from the small space around the stove.

Conclusion:
I'd advice to have the same type on pipe with insulation between small and large. This is fundamental.
The cowl brings a huge improvement, even it is not perfect. I can't say compared to the H cowl.
I'd advice to install a good quality stove. If you want an insert, choose to install a heat recuperation unit at least for the room.
See here or for the all house here to have an idea what it is.
An external wood stove can heat the room without any other install. Moreover you can install a regulator on the pipe , here, here.

I hope this will help.

Caspero

Thanks very much Trompette for taking the time to give a very detailed answer.