Because the Aderyn cowl faces away from any wind, a low pressure zone is created on the lee side just above the chimney pot. The result is better chimney function, which reduces the chances of tar and creosote formation that can occur in sluggish flues.

The wind blowing across the top of any chimney is rarely a smooth, steady, laminar flow. The proximity of another building, trees, adjacent roof pitches or other feature will cause turbulence which can frequently cause problems. Obstructions often produce ‘rotors’ that result in reverse flow in the chimney, or downdraught. Everyone has experienced reverse flow, which is commonly only temporary, but causes the fire or stove to puff clouds of smoke into the room. No cowl can be guaranteed to cure all types of downdraught as the causes are so varied, but tests and observations have shown that the Aderyn cowl is one of the best at doing exactly that because unfavourable downward air flows are split by the cowl and directed over each side of the pot, and the low pressure zone just above the pot is pre-served, maintaining chimney function. The Anti Downdraught Cowlis the most popular compact anti downdraught cowl on the British market. The reasons for this are that its compact and aerodynamic shape allows it to combat downdraught. Alongside this, it features a drainage system designed to divert rainwater away from the pot when in use, whilst the internal stainless steel bird guard prevents birds leaves and vermin entering the chimney. As with all MAD cowls, the quality on offer surpasses that of equivalent inferior models being offered elsewhere. TheAnti Downdraught Cowl Benefits Explained further– It is our opinion that no spinning/revolving chimney cowl is suitable for use with peat or smokeless fuel without increased levels of annual maintenance, that is why we do not offer a guarantee when these fuels are used. Mentioned within our product bulletin above gives customers an insight into the vast knowledge we possess in the field of metal engineering. Be assured we know the limits of the materials used within this product type; It is our expressed opinion that no spinning/rotating chimney cowl can cope with such acidity levels on a prolonged basis, without failing. If it is your desire to use the spinning cowl with smokeless fuel, all we ask is to be prepared to carry out maintenance at shorter intervals. That said, our spinning cowls are made to the highest standards, and should a customer want to use a MAD Spinner cowl outside our warranted recommendations, then we have spares on hand, to ensure that our spinning cowls can be serviced and/or repaired more frequently.The MAD cowl is the most popular compact anti downdraught cowl on the British market. The reasons for this are that its compact and aerodynamic shape allows it to combat downdraught. Alongside this, the M.A.D cowl features a drainage system designed to divert rainwater away from the pot when in use, whilst the internal stainless steel birdguard prevents birds leaves and vermin entering the chimney. As with all M.A.D cowls, the quality on offer surpasses that of equivalent inferior models being offered elsewhere. MAD Cowls – the provider of “problem solving chimney cowls”– was established in 2005. In the past 12 years, they have built a solid reputation as a trustworthy supplier and become one of the biggest brands in the field.

Launched in 2005, the M.A.D (metal anti downdraught) brand of chimney cowls has become the most dominant brand in the UK.The aerodynamic design and quality of the twin sealed bearings ensures that the Aderyn cowl responds instantly to any breeze, protecting the chimney at all times. Regardless of which chimney problem you’re struggling with, MAD Cowls offers the most comprehensive range to help you solve it. Fully committed to solving all chimney related issues, MAD Cowls offers technical expertise and industry knowledge that is second to none. This has enabled MAD Cowls to design the most innovative solutions and offer the most aerodynamically shaped products to cement their market dominance. The cast aluminium base is exceptionally free-flowing and offers very low impedance to flue gases. The open body of the cowl has a clearance area greater than the chimney pot cross-sectional area and likewise offers very low impedance to smoke and flue gases. An effect of standard Chinese-hat type cowls which is not often appreciated is the tendency for smoke to ‘bounce’ off the underside of the cap and travel downwards thereafter. To understand the effect, try holding a spoon the right way up under a running tap! In certain conditions, this is enough to send the smoke right down to the ground where it can become a nuisance. By contrast, the Aderyn Cowl simply deflects the smoke, which can continue to rise at all times. When used with seasoned wood, coal or oil your spinning/revolving chimney cowl will need to removed each year and cleaned. We feel that other brands that do not mention this are misleading customers into thinking that the model they offer will not need this maintenance. All spinning cowls unless used with gas will inevitably suffer debris build up, this debris will need to be removed to ensure the product keeps spinning.

The MAD Cowl is not to be used with smokeless fuel. It is recommended using the MAD Junior Stainless Steel or MAD Senior Stainless Steel when in use with more corrosive fuels such as smokeless fuelColt Cowls supply the largest range of chimney cowls in the UK, and have a reputation for producing the highest quality chimney cowls and chimney birdguard cowls available on the market. Painted versions have a corrosive resistant powder coat finish, which makes it suitable for all fuels (see fuel chart) The nuisance caused by birds, small animals and leaves entering the chimney can be resolved by fitting this cowl. MAD Cowls manufactures 3 different models of static anti-downdraught chimney cowls – the Senior, the Junior, and the MAD. All models have an aerodynamic shape that will divert directional wind across the top of the chimney to draw the smoke out and preventing downdraughts.

IMPORTANT– Spinning cowls are not suitable for use with peat, smokeless fuel, or freshly cut unseasoned wood. Any guarantees are void in conjunction with these fuels. Colt Cowls are rightly proud of the quality of chimney cowls they produce, and are the ONLY chimney cowl brand with BSI Kitemarked chimney cowls, and or course where relevant all Colt Chimney Cowls are tested and certified under the new regulation BSEN 16475-7:2016 and BSEN-1856-1:2003.Compact design which allows it to be fitted side by side where space between chimney pots is restricted The M.A.D cowl range is by far the best quality and most comprehensive range of chimney cowls to help solve every type of chimney-related problem. Recently, Colt Cowls have also launc hed the new ECONO range of chimney cowls and birdguards including the Econocowl®, the Econolid® and the Econoguard®& Econotop ® which are all aimed at the budget chimney cowl end of the market.