How to reduce whistling due to wind across a gas fireplace vent

chimneyexhaust-ventnoisevent

We have a gas fireplace venting through the roof of our attic bedroom; there's a cap on a chimney up there. Double-wall construction, such that it pulls combustion air in from outside.

When the wind blows, the vent whistles loudly.

How can I reduce this noise?

Best Answer

The first thing I would check, is to make sure there are no blockages in the vent. If there is debris restricting the flow of air, it could produce noise.

Another cause of this could be that the wind is blowing just rught across the top of the pipe causing it to vibrate, similar to blowing across the top of a bottle to produce sound. To prevent this, you could try cutting small V shaped notches around the perimeter of the end of the pipe.

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Cutting the end of the pipe at a slight angle (2-5° < 90°), may also prevent the wind from crossing the end of the pipe in a way that produces noise.

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