Wind's Effect On Draft???

If you don't have a chimney cap, typically what I've seen is if the wind is hitting the roof on the side where your chimney is located, the draft increases substantially, if the wind hits the opposite side and "rolls over" the roof it may force a downdraft/backpuff. Chimney cap should help prevent the backdrafts (but draft may still accelerate if it hits the side with your chimney) and having the flue exit 2ft above the peak should help too.

Usually it burns my wood up quicker with a good strong south wind, its weird as the temps in the stove dont change much.

oldspark said:

Usually it burns my wood up quicker with a good strong south wind, its weird as the temps in the stove dont change much.

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/ this. We had pretty high winds last night and the stove was eating wood.

Just switching to a newer stove eliminated all kinds of wind issues.
I have had draft issues in the fall at times but it wasn't wind related, I don't believe.
Kenny

Wind was crazy last nite and so was the draft. Talk about wood eating.

BeGreen said:

In some cases a special cap can help mitigate the effects.

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I have heard about the Vacu Stack. Are there others that are worth considering?

Thanks.

Does anyone out there have issues with the cold metal caps causing the smoke to condensate onto the cap?

You could try using the Flue Cube

http://www.fluecube.com/

Seriously though, I think it would be interesting to see if it would help with overdraft.

https://www.hearth.com/econtent/index.php/wiki/Effect_of_wind_on_chimney_caps/

I'd done some tests and research myself on this stuff - basically you can't say much for certain because it depends on so many factors! In general, the vacu-stacks don't work too well - the study shows that the standard type of cap can work as well or better than most!

The rotating type can work very well with strong winds from one direction (coastal).

A barometric damper in the stove pipe can help even out the pull of winds...

It seems to depend on wind speed and direction. Sometimes the wind kills my draft, other times it Turbo charges it.

-SF

[quote author="BeGreen" date="1326945302"]I've been wondering if the flue cube is using another variation on the Bernoulli effect to enhance draft? If so, there are devices on the market that do the same for a lot less.


Yes true, the globally patented FlueCube design does benefit from the Bernoulli effect. All that is needed for that is it's flat mesh top and air to flow over top of it. Voila, uplift! That allows the fire to be lit easier in poor weather or on these high inversion days. The part that is ignored in almost all other cowls, is it's cubic shape and cone that allows the two temperatures of air to react with one another and maintain a consistent vacuum, no longer affected negatively by external forces.

Heat typically travels straight up a cylindrical pipe and hits colder air coming down from the opposite direction. The larger quantity of heavier, colder air suffocates the ability to combust efficiently and effectively below it. A cold cylindrical chimney can mean a very difficult (and polluting) smoldering heat source. The old square chimneys were in fact draft inducing (with an open fire from above and below it), but was the shape of chimney changed because of this or was it just more economical in the use of steel? Think about it.

FlueCube International prefer to source provincial manufactures to build their cowl wherever it is on sale. It is also a young, growing business, so it will cost a little more than other mass produced cowls initially. Sorry about that but it does use high quality heat grade stainless throughout and will likely last for generations. Unlike the genious of other consumables it's not designed to rust or break. I also believe the practical greener thinking consumers are more ethical/ conservative in their choice of product purchase than the other more materialist minded consumers. Quality over quantity, sustainability over profit and all that other anti-economic stuff. They also support off grid self sufficiency, which the top down policies of the EPA education programme strangely does not - electric start pellet burners, electric fans, natural gas fracking, health scare-mongering junk science and cost benefit analysis. I personally believe the HPBA should never have got involved with them.

With a strong gust hitting our chimney, I seen draft jump by 6x's on a manometer. Sounds like a jet.

Holy draft! Last night we had REALLY strong winds, it was sucking the fire right up. I've never seen it draft like that, it was insane. I ended up rearranging the bricks and splits to the back of the stove and packed the up tight (well, as best as I could using the poker). It actually sucked some small embers (like dust speck sizes) off the ecobricks right up the flue too! WOWIE. Kept me up late keeping an eye on the stove.

I need to get my own weather station, because it was showing winds at 17mph and there was NO way that's all they were.