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Push-Fit Smart OH Cowl

Push-Fit OH Cowl

These Cowls have been specifically designed for use with Chimneys that terminate with an ornate Chimney Pot. They simply push into the Terminal and are held permanently in place by a series of teeth which grab the inside of the terminal. The unique and patented design allows for removal of the Cowl if required at a later stage.

Push-Fit Smart OH CowlDesigned to Increase Updraught and Prevents Rain Ingress

OH Cowl Stainless Steel Finish

Steel Finish Push-Fit OH Cowl

OH Cowl Cream Finish

Cream Finish Push-Fit OH Cowl

OH Cowl Black Finish

Black Finish Push-Fit OH Cowl

OH Cowl Terracotta Finish

Terracotta Finish Push-Fit OH Cowl

Push-Fit OH Cowl is suitable for most conventional clay chimney pots with an 8 inch (200mm) internal and 9 inch (230mm) external diameter. H Cowl is designed to prevent foreign bodies entering chimneys, to increase updraught and to prevents rain ingress. Designed for situations where the chimney is too short (conservatories) or where the chimney doesn't clear the ridgeline of the house, OH Cowl is the best Chimney Cowl you can choose for downdrought problems.
It is designed to be secured to the Barbed Section which is pushed in the Chimney Pot. Push-Fit OH Cowl is available in 4 finishes which are illustrated above.

How OH Cowl Works

OH Cowl Section

In normal or still air conditions, the hot gases and smoke pass up the chimney and exit out of the top of both of the vertical tubes.

OH Cowl Section

If wind drives downwards in turbulent conditions, the air moving down the tubes increases in velocity because it is restricted as it is forced through a narrow gap as it passes over and around each end of the horizontal tubular section projecting half way into the vertical tubes. The increase in velocity, basically a venturi effect, induces suction as it passes the horizontal tube and the hot gases and smoke exit out of the vertical tubes. Any upward gusts of air will also act in a similar manner, so this design of "OH" cowl becomes very effective in windy conditions where the chimney is subject to "downdraught".


  • »Promote positive updraught;
  • »Fits most conventional chimney pots;
  • »Made from Corrosion proof Stainless Steel;
  • »Durable Construction;
  • »Quick and simple to install;
  • »Prevents rain ingress.

Our Price: €164.95

Sale Price: €154.95

Buy OH Cowl

Push-Fit OH Cowl InstructionsStep by step installation procedure

1. In the box you will find the following components:

2 x Stainless Steel Bands A - these are only required if the chimney pot is cracked or in need of support.

1 x Stailess Steel Chimney Cowl B pre fitted to insert C and secured with 4 no, screws D.

Step1 H Cowl

2. (Optional) Fit the securing bands around the Chimney Pot as close as possible to the top. These are only required if the pot is obviously cracked or has become fragile. We recommend using them if for example you know or suspect that the chimney has been subjected to chimney fires. They provide additional support to the walls of the terminal which will be subjected to some pressure when the barbed insert is fitted.
Disassemble the chimney cowl B from the insert C by removing the 4 stainless steel screws D.

Step2  H Cowl

3. Wearing glowes, carefully push the barbed insert into the chimney pot or terminal ensuring that both components remain parallel whit each other. Do not push the insert past the "bead" which should sit at the top of the pot.
The insert features a double row of "barbs" which facilitate its insertion into the chimney pot while at the same time preventing it from coming out. they grip the inside of the pot and become stronger if force is applied.

Step3  H Cowl

4. Ensure that the insert C cannot be pull out of the chimney pot. If it is possible to do so, it is because the internal diameter of the pot is greater than 200mm. To overcome this problem it will be necessary to increase the angle of the stainless steel barbs. This can easily be done by using a pliers. Push the insert into the chimney pot ensuring that the barbs are touching the walls of the pot and that there is feeling of resistance.
Place the chimney cowl over the insert and realign the 4 holes. Step4  H Cowl

5. Reinsert the stainless steel screws ensuring that they are adequately tightened. It may be necessary in the future to remove the chimney cowl to facilitate chimney cleaning or the removal of tar and soot deposits from the stainless steel mesh which is there to prevent birds from entering the chimney. Step5  H Cowl

6. If in the future, it is necessary to remove the cowl, it will be possible to do so by undoing the 4 screws and lifting it off the barbed insert.
Owing to its unique grip features, it will not be possible to easily remove the barbed insert. However with the use of a thin snips tool it would be possible to carefully cut it out. Step6  H Cowl

DownDraught Explained

DownDraught Explained Part 1
DownDraught Explained Part 2
DownDraught Explained Part 3
DownDraught Explained Part 4
DownDraught Explained Part 5
DownDraught Explained Part 6
DownDraught Explained Part 7
DownDraught Explained Part 8
DownDraught Explained Part 9
DownDraught Explained Part 10
DownDraught Explained Part 11
DownDraught Explained Part 12
DownDraught Explained Part 13
DownDraught Explained Part 14
DownDraught Explained Part 15
DownDraught Explained Part 16
DownDraught Explained Part 17
DownDraught Explained Part 18

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