Advice please for built-in recirculating kitchen extractor

[offthepiste]

Hi,

I am hoping someone might be able to advise. Am trying to find out which are the "best" recirculating kitchen extractors that can be built-in (aka integrated?) 650mm above 800 -900mm wide induction hob - and which can be fitted with an active carbon filter.

 

I stress the built-in / integrated aspect of this.

 

Our home retrofit will be relatively airtight and we will have a Zehnder mvhr with appropriate supply & extracts throughout the house.

 

Was interested in the Falmec "no drip" extractor models but seem impossible to source in the UK. "no drip" as they have an interesting solution to catch condensation - we have a temporary rental and have observed this problem in spades.

 

Also I very regularly cook / griddle fish - hence need for a really robust solution. And would like to minimise our exposure to cooking generated PM,.5s!

 

Thank you in anticipation, cheers

 

 

 

 

Edited September 19, 2022 by offthepiste

[JohnMo]

Go with as good an energy rating as you get your hands on.  Also look at grease filter performance and noise.  Availability could be the issue.

[Lilly_Pines]

Recirculating is practically useless for particulates (example). Assuming the extractor catches all cooking fumes as they're produced, you need a HEPA-grade filter to properly remove the finer and most harmful pollution. If you aren't filtering almost everything away on the first pass they will make their way into the general breathing air and you'll be waiting for the recirculator to gradually whittle them down over time. I have never seen a consumer-grade recirculator with adequate filtration, only large and expensive commercial units. At that point it's probably easier and cheaper to get a real extractor and supply air setup.

Edited September 20, 2022 by Lilly_Pines

[JohnMo]

Or don't fry

[Lilly_Pines]

I couldn't immediately find whether Zehnder MVHR units can balance the pressure of the house by supplying the make-up air for the extractor, but that's the first place I'd look. Theoretically all it'd take is running the supply fan a lot faster than the extract fan so it's just a question of controls and whether the MVHR has enough capacity for the extractor.

[JohnMo]

Just open a window a bit.  I have no issues with the recirc unit.  Only have it on if frying which isn't very often.  MVHR looks after the rest on boost.

[Temp]

I think some extractors can be configured for extract or recirculate. Our extractor doesn't seem to cause our mvhr any issues. Nor the wood burner. 

 

Perhaps you could try one as an extractor and reconfigure it to recirculate if it causes an issue?

[offthepiste]

Thanks to all, cheers

[Adsibob]

Based on my experience, i would avoid a recirculating fan. We initially installed a very expensive one made by Novy, and it was very loud and not very effective at getting rid of smells, in spite of having expensive carbon filters in it. We eventually drilled a hole through the wall and vented directly outside. This has made the same Novy unit much quieter. Because we have MVHR and an airtight house, for it to work well, the MVHR company recommended we crack open a window, literally just a 3mm - 4mm gap is enough on a medium sized window. I've been monitoring to see whether the temperature in the kitchen drops when we do this, and haven't noticed any drops, although at the times i've checked the delta between indoors (20C) and outdoors (9C) was only 11C. Maybe it is more noticeable when the external temperature is lower, it will be rare that delta would be more than 15C or 16C.

 

[Mr Punter]

I have an extractor with an external motor. Grease filter only. It is really nice and quiet and no cooking smells. 

[Sparrowhawk]

On 30/09/2022 at 16:24, Adsibob said:

I've been monitoring to see whether the temperature in the kitchen drops when we do this, and haven't noticed any drops, although at the times i've checked the delta between indoors (20C) and outdoors (9C) was only 11C. Maybe it is more noticeable when the external temperature is lower, it will be rare that delta would be more than 15C or 16C.

 

How did it perform during the recent cold snap?

 

On 30/09/2022 at 17:36, Mr Punter said:

I have an extractor with an external motor. Grease filter only. It is really nice and quiet and no cooking smells. 

I'm wanting to use an external extractor this time as our current internal one is noisy. Which do you have, and how well does it stop draughts when not running?

[Mr Punter]

1 hour ago, Sparrowhawk said:

I'm wanting to use an external extractor this time as our current internal one is noisy. Which do you have, and how well does it stop draughts when not running?

 

It is an S & P inline fan mounted in the plant room above the kitchen.  There is a draught flap on the outside vent.  You could not mount this one open to the elements.

[Adsibob]

On 21/12/2022 at 08:19, Sparrowhawk said:

How did it perform during the recent cold snap?

Not much impact from the extractor on and the window cracked open. But my measurements are not that accurate because my kitchen thermostat (which tracks the data) is actually not in a great location. Much closer to the oven than to the cracked open window. I should probably use a separate thermometer to take measurements nearer the window. I think that as long as you only use the extractor once or twice a day and only for 30 minutes at a time, the impact is largely going to be minimal and partly offset by the heat generated from cooking. But the purist in me wishes we had gone for a Bora hob with integrated recirculating extraction, as this would send the extract to grills by the floor, where they would not be as noticeable as our original recirculating configuration, which is what caused us to change to non-re-circulating.