Kitchen extractor fan – is recirculating OK?

Do recirculating cooker hoods work? We’re moving our hob into the middle of the house which will mean that the ducting run for the hood would be about 9m including 1 right angle bend. It’ll all be in one big kitchen/living room, so there may be no issues with condensation. The local kitchen shop has recommended a recirculating hood rather than ducting. We cook a lot so I’m not fully convinced. Anyone have a comment?

Got one here, don’t like.

Go for extractor if you can make it work.

Ours recirculates and is less than ideal.

If it doesn’t duct to outside it won’t do much good at all. All yo are doing is filtering the smells not getting them out of the house.

I don’t think building regs permits recirculating hoods for new kitchens. Not sure if the applies to existing space and just moving it.

Ducted will be miles better though.

I was glad to get rid of my recirculating one and fitting a ducted one. Sooo much better.

I have both a recirculating hood and a whole house air handling system/

The recirc hood is best way of getting rid of airborne grease.

Then I have a kitchen extract (and heat recovery) about 3′ from the recirc outlet.

Keep the grease filters clean (dishwasher)
and replace carbon filters as and when.

Dont see why it cant work in a well ventilated room even if you have to recirc.

Ducted every time, not only gets rid of the smell and grease, but most importantly steam so there’s no condensation problems.

APF

Use the recirculating hood and add an extractor fan through the nearest available outside wall?

Hmmm – so only Stoner has one and is happy – and he’s got an air handling system as well.

Thanks all for the reports.

As above recirculating are ok for getting rid of smells, but they wont take the moisture out.

It wasnt until we got our kitchen refitted 2 years ago and got a decent powerful extractor that I realised just what a difference an extractor makes to condensation etc.

As to building regs.. the regs are that you need a fan extractor (like the type you get in bathrooms etc) an extractor hood is not a reg. However since the building inspector left our house the reg one has been disconnected, but we use the extractor hood all the time

Ducted if possible, else you need carbon filter for smells and a grease filter.

better than nothing! with carbon filter it will capture a fair amount of grease which would otherwise end up in the air and settling on the cupboard tops etc

but duct if at all possible

[Edit] mine recirculates and in hindsight would have made more effort at sorting a duct [/Edit]

Ducting that length will work as long as the ducts are wide enough. Standard is 100mm, if you can go 150mm or even bigger you’ll get much better airflow. Also avoid those concertina type wire and plastic pipes for the bends, they just make the airflow more turblent and therefore less efficient.

Ducting that length will work as long as the ducts are wide enough. Standard is 100mm, if you can go 150mm or even bigger you’ll get much better airflow. Also avoid those concertina type wire and plastic pipes for the bends, they just make the airflow more turblent and therefore less efficient.

Are you sure? I’d have thought turbulent was better at stopping the grease falling out of the flow and settling in the ducting, bigger ducts would just sow the air down and lead to an accumulation of grease and debris?

29erKeith – the foil filters before the carbon filters deal with the grease. They are washable. The carbon filters (active carbon) are odour removers. Getting grease on/in them stops them working.

Recirculating fan has about 70% of the efficiency of a ducted one as long as filters are in good condition, however extraction rates can vary from 230 up to 850+ cubic meters per hour so a recirculated high end one can actually be better than a lkow ducted.

Having said this to work correctly a extractor should be on for about 20 mins b4 cooking to ‘get the flow going in the right direction’. No one does this so alot of the above is immaterial tbh

As to building regs.. the regs are that you need a fan extractor

According to the Goverment’s planning portal website this is only required if there are no openable windows.

We didn’t really have a choice, so we have an recirculating one. Have to say it’s next to useless, it makes all the right noises but does do anything. Still need to keep the window open if you have something on the boil.

Having said this to work correctly a extractor should be on for about 20 mins b4 cooking to ‘get the flow going in the right direction’. No one does this so alot of the above is immaterial tbh

How on earth does that make sense?