Downdraft extractors

[dannyboy123]

I really need some help with down draft extractors. I would prefer to have a ceiling extractor above our soon to be installed kitchen island but with the structural beams I dont think it's possible so I'm stuck with a down draft. The duct will have to go into the concrete floor and I'm guessing come back up the inside wall and then through to the outside. I'm struggling with the concept of hot air going down and I'm also struggling with stopping grease entering the ducting because in essence you create a u bend. Does anyone who has installed one like this have any experience...do the actually work?

[lizzie]

Do you have MVHR?  If so outside extract is not usually recommended.

[nod]

41 minutes ago, dannyboy123 said:

I really need some help with down draft extractors. I would prefer to have a ceiling extractor above our soon to be installed kitchen island but with the structural beams I dont think it's possible so I'm stuck with a down draft. The duct will have to go into the concrete floor and I'm guessing come back up the inside wall and then through to the outside. I'm struggling with the concept of hot air going down and I'm also struggling with stopping grease entering the ducting because in essence you create a u bend. Does anyone who has installed one like this have any experience...do the actually work?

I did this if it’s any help

All singing all dancing Italian extractor To be dare we have only used on the lowest setting  

[joth]

If you don't have MVHR, another option is a recirculating down draft, and the a separate extractor fan over on the wall. 

For building regs only the latter is strictly needed, I think

[dannyboy123]

4 hours ago, lizzie said:

Do you have MVHR?  If so outside extract is not usually recommended.

No we dont have mvhr

[dannyboy123]

3 hours ago, nod said:

I did this if it’s any help

All singing all dancing Italian extractor To be dare we have only used on the lowest setting  

That does look awesome. Unfortunatly my ceilings are not that height and with the beams something like that might look silly. I would much prefer a ceiling extract...is that luxair?

[MJNewton]

4 hours ago, dannyboy123 said:

I'm struggling with the concept of hot air going down

 

It's simply down to pressure. Same way that water is made to flow 'uphill' in pipes... :-)

[lizzie]

The hot air goes down in my Bora which has the extractor integrated into the hob......its quite fun to watch when there is nothing on TV?

[MJNewton]

Ah, you've just made me realise what dannyboy was probably wondering - not how the hot air goes through the duct but whether it would it would be sucked into it in the first place! Apologies dannyboy!

Edited July 19, 2019 by MJNewton

[dannyboy123]

13 hours ago, nod said:

I did this if it’s any help

All singing all dancing Italian extractor To be dare we have only used on the lowest setting  

Out of interest, what it the distance between your island top and the extractor?

[nod]

39 minutes ago, dannyboy123 said:

Out of interest, what it the distance between your island top and the extractor?

I build quite a lot of these and always line them with the door openings 2110 Giving about 1200 from extractor to worktop 

[ryder72]

Building these bulkheads is only really needed to get around joists etc. In a new build there is no reason why these extractors shouldnt go flush into the ceiling.   Ceiling hoods are great for extracting odours but not necessarily to remove grease.

 

On a downdraft hood, your grease filter should be catching most of the grease and very little getting into the ductwork.

 

 

[dannyboy123]

On 19/07/2019 at 23:30, lizzie said:

The hot air goes down in my Bora which has the extractor integrated into the hob......its quite fun to watch when there is nothing on TV?

Lizzie, what height pans do you get away with on the bora so it still extracts? I'm thinking about the steamer situation where the pan top may be 30cm above the hob? 

[lizzie]

47 minutes ago, dannyboy123 said:

Lizzie, what height pans do you get away with on the bora so it still extracts? I'm thinking about the steamer situation where the pan top may be 30cm above the hob? 

I use a three tier steamer pan with no issues it still draws the steam perfectly.