H Anti Down Draught Chimney Cowl

The H Anti Down Draught Chimney Cowl is a stationary cowl that is designed to solve bad down draught problems.

Ideal for situations where there is a short chimney such as a single-story dwelling or bungalow. However, it is also very effective protecting longer chimneys from down draught.

The H chimney cowl will also protect the chimney from extreme driving rain situations and is probably the best cowl in the SHL range to stop moisture ingress caused by rainwater.

Only available in a stainless-steel finish to fit a standard 200/230mm or 8″/ 9“ chimney pot.

Suited to both long and short chimneys. Because it has no moving parts, this chimney cowl will last a very long time.

Constructed from robust stainless steel.

The SHL H cowl works in 5 ways:

1. In still or calm weather conditions, the hot gases and smoke rise up the chimney and exit from the top two vertical tubes of the H shaped cowl.
2. If wind drives downwards in turbulent weather conditions, air is forced down through the top vertical tubes and this air draws the smoke out of the chimney (Venturi effect) and expels the smoke / gases from the downwards facing tubes.
3. And visa versa, if the chimney experiences the opposite, where wind moves upwards through the H cowl, smoke is drawn out (Venturi effect) and up through the H chimney cowl.
4. If the wind blows across the roof and therefore across the cowls 4 openings, smoke is drawn out of the chimney through the Venturi effect.
5. Lastly, because the cowl completely shields the flue from rain, this anti down draught cowl excels at stopping moisture entering the flue.

Fitting:

This product is very simple to install. Insert the base (190mm Ø) of the chimney cowl into the top of the chimney pot and fasten strap with nut and bolt. Tighten completely with a screwdriver.