Best Chimney Cap for a Windy Location?

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I am having my chimney lengthened (made taller) and getting rid of my old whirly bird chimney cap.

I live on a cliff overlooking Puget Sound, so there are strong winter winds. I would very much like to know what chimney cap to purchase that will keep the down drafts to a minimum. Also, if there is a cap out there that helps "pull" the air up a chimney liner I'd like to know that too.

Does anybody know?

Thanks!
 
I've been reading about the Vacu-Stack and it sounds good. Does it produce a venturi effect which would create a vacuum on the inside of the chimney as the wind is blown against the vanes?

I have always liked a wind directional whirly bird for the beach area, although have never used one on a 6" liner. Do they work well too with liners?
 
I have a vacustack. It does not produce a venturi effect, simply eliminates any line of sight path for outside air to go straight down the chimney pipe. It did improve issues I had with backpressure during big gusts, but did not eliminate the issues altogether. However, in my case I'm also dealing with stack height issues and will be adding another 5' of pipe to my chimney in the coming weeks. Overall, I'd recommend the vacustack.
 
I am having my chimney lengthened (made taller) and getting rid of my old whirly bird chimney cap.

I live on a cliff overlooking Puget Sound, so there are strong winter winds. I would very much like to know what chimney cap to purchase that will keep the down drafts to a minimum. Also, if there is a cap out there that helps "pull" the air up a chimney liner I'd like to know that too.

Does anybody know?

Thanks!

How far is your chimney from the top of the bluff? If you see seagulls soaring on the updrafts (without wings flapping) there will be strong downdrafts and lots of turbulence landward of the soaring path. Like this:

page195-1.jpg
 
In your drawing, there is a light blue section. We are at right at the right side of the light blue section, where the dark blue section begins. We get hammered by south / south east wind. I have heard that the chimney cap from Reliance is better than the Vacu Stack. ( https://tinyurl.com/yc4xmg3m ) Does anybody here have experience with this type of cap?
 
In your drawing, there is a light blue section. We are at right at the right side of the light blue section, where the dark blue section begins. We get hammered by south / south east wind.

In reality, that drawing has no particular scale to it, it's just a conceptual visualization.

In practice, a sharp-edged bluff with a vertical face near the top will have a very short (but powerful) zone of influence while a bluff that is more rounded (as in the illustration) will have effects extending much further back. Stronger winds move the zone of influence further downwind.
 
In reality, that drawing has no particular scale to it, it's just a conceptual visualization.

In practice, a sharp-edged bluff with a vertical face near the top will have a very short (but powerful) zone of influence while a bluff that is more rounded (as in the illustration) will have effects extending much further back. Stronger winds move the zone of influence further downwind.

I'm not sure about all that, but we get hammered during the winter winds! My whirly bird chimney cap works very well, but my chimney guy tells me that it's too big for a new 6" liner and that the Reliance cap works very well with the liner and the wind. I hope he's correct!
 
By "whirly bird", do you mean the "rooster tail" style. We used to use the "rooster tail" style down at the beach all the time on wood heaters & fireplaces & they work well. We had one for years on our Fisher stove & it was fine, but did need periodic cleaning (along with the chimney), as the old Fisher seemed to make a lot of creosote (partly due to the triple wall hollow chimney design of old).
 
Yes, that's the one I've used for 40 years! I use to clean it with a very small/narrow brush on my drill annually, to get all the rust and gunk out. I used all sorts of greases and graphite's, etc to make it swing easy. Always had maintenance. A few years back after cleaning I dropped a very small SS ball bearing down the tube and greased the male part with White Lightening. Since then, no squeaks, no cleaning, always turns with ease. I won't be able to use it any longer because there will be 2' of Class A pipe rising up above the top terra cotta flue liner. The Whirly Bird / Rooster Tail is build to go down into the flue liner about 15".
It's been a great chimney cap, and look very nautical too.
 
The "rooster tail" caps are available for 6" & 8" chimney types -- do a search online for them. Probably would be your best choice where you are located.
 
I have a vacustack. It does not produce a venturi effect, simply eliminates any line of sight path for outside air to go straight down the chimney pipe. It did improve issues I had with backpressure during big gusts, but did not eliminate the issues altogether. However, in my case I'm also dealing with stack height issues and will be adding another 5' of pipe to my chimney in the coming weeks. Overall, I'd recommend the vacustack.
did you ever measure your draft before and after the vacustack.
 
Yes, that's the one I've used for 40 years! I use to clean it with a very small/narrow brush on my drill annually, to get all the rust and gunk out. I used all sorts of greases and graphite's, etc to make it swing easy. Always had maintenance. A few years back after cleaning I dropped a very small SS ball bearing down the tube and greased the male part with White Lightening. Since then, no squeaks, no cleaning, always turns with ease. I won't be able to use it any longer because there will be 2' of Class A pipe rising up above the top terra cotta flue liner. The Whirly Bird / Rooster Tail is build to go down into the flue liner about 15".
It's been a great chimney cap, and look very nautical too.
could you use a storm collar with the w bird?