Cooker hood breeze

Jan 28, 2020 Last reply: 6 years ago 23 Replies

Does it have "back draft shutters" fitted? They are thin light plastic spring loaded flaps (usually a pair, each semi circular) usually mounted immediately before the ducting connects to the fan output spigot.

They are pushed open by airflow from the fan being on, then when fan is off they shut due to their springs. You usually hear them as they "slap" shut after the fan is switched off...

Utter bollocks - they are a standard fit.

The grease soon jams them.

The filters are there to filter the grease before it gets through the fan...

In our kitchen we have a perfectly ordinary cooker hood vented outside. Trouble is, there is quite a draught from it. It exits into the gap between our house and our neighbours' - which can be pretty windy. Fine when cooking, but makes the whole kitchen a bit chilly in the winter.



Is there a simple (but effective) way of reducing airflow when we are not using it?



Obviously we could shove a rolled up newspaper in the hole - but that is hardly convenient!


When switched on or off, it makes no noise (other than the motor).

I didn't fit it - so will check out the documentation and have a look. Thank you.

You could try a cowl vent or flap vent as shown here:

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Either can help, but aren't perfect. The cowl vent can let some air in as it's still open to the outside. The flap vent is closed, but the one I used would make a noise as wind rushed past it and pulled it open, allowing it to fall back when the wind dropped, and make a tapping noise. I had to fit a sort of restrictor so it could open only a cm.

I should have gone out and checked what is visible on the side! :-) Because of the arrangement of houses here, we virtually never even look up that side. (Not that it is a problem to do so!)

Will check in the morning.

Thank you.

You can get external versions as well - ours has three horizontal shutters, each hinged from its top edge. They are not as good though, ours sometimes blows up and gets one trapped behind the one above, stopping it closing properly.

SteveW

If it hasn't and it isn't easy to fit one a less effective but useful alternative is a louvred vent on the outside wall with slats that close up when there isn't any outflow. These can be relatively easily retrofitted. Example:

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Some cowls also have the inbuilt flap that only opens with airflow from one direction

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I have one fitted to an extractor fan BUT I had to shave around a quarter of inch off the bottom of the flap to give more clearance so it operated smoothly.

Note: the link above maybe the wrong size fitting for your ducting

If it already has one of those, it isn?t unknown for one or more to either get stuck open - sometimes a bit of muck or just having been forced too far by the wind etc- or be broken off. The one on our bathroom seemed especially prone at one stage until I changed it.

There are gravity closed airflow opened shutters - you might have one that's stuck open. They blow open in wind and stick open on occasion. Then there are solenoid & wax motor powered flaps, they're much better, staying shut when they should. Solenoids go clunk when they operate, wax motors are silent. Both require power.

NT

They do tend to flap open and shut in blustery weather though, making a bit of a racket. The ones inline with the duct tend to be a little better and quieter IME.

They can't be fitted to cooker hoods. The grease soon jams them. Usually the metal filters stops much backdraught. Are the filters fitted?

The vent on my cooker hood has flaps on it which only open when the fan is running. You used to be able to get electrically operated ones , too.

Rubbish - mine works even after 31 years. The filters in the hood collect thgrease.

SF doesn't seem to have a cowl vent suitable for 150mm - I'd guess that most ext. fans for kitchens are 150mm - cooker hoods could be smaller. I used the 'giant' version to ensure that the open area was a lot bigger than the opening of the fan. Selection here:

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In a domestic cooker hood the grease filter is usually the first stage of filtering. You want to stop grease, that may go rancid, from entering and lining the ducting.

And constantly slapping open and shut when we have strong gusty winds :-<

In message snipped-for-privacy@candehope.me.uk>, charles snipped-for-privacy@candehope.me.uk> writes

While we are here... has anyone found an easy way of stopping horizontal vent flaps rattling in windy weather?

I mean to wrap a turn of duct tape around ours.

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