Vent Pipe

[Old_Geezer]

Ok, I've been ages getting my kitchen right but I like to think I'm going to be on the last leg soon. My present issue is with venting the air extractor to the outside world.

The existing hole in the wall, and the cover on the outside, is a standard 100mm diameter. I note when I come to install the extractor that it specifies it needs to connect to a pipe with a 120mm inside diameter. Like a fool I thought these things would have standard sizes.

I bought a 120mm to 100mm convertor from the local DIY shed. I place it on the extractor, it is loose. Measuring it, it is more like a 123mm inside diameter !

It said it was a female to female connector (the DIY shed only sold one type) so in a fit of inspiration I figured just maybe it should fit over a standard 120mm pipe, and maybe the 120mm pipe fits over the extractor outlet. As if it was going to be that easy.

I bought a short length of 120mm (5") pipe, and when checked it was the SAME DIAMETER as the convertor.

I'm running out of ideas. Does anyone make the conversion I require, or even pipe that really is 120mm internal diameter ? Or is it all just a joke ?

In desperation I tried just placing the convertor over the outlet. The fan blew it off immediately. Of course I could gum it all up with glue, or silicon or something, but I was hoping to do this properly.

Anyone have a solution ? Thanks.

[The Builder]

125mm (5") is the standard for extractor hoods OG. This one is the type usually used........

http://www.screwfix.com/p/manrose-round-reducer-125-100mm/10684

If that's what you have bought, then I can only think your extractor is some rogue size. Try this............

http://www.screwfix.com/p/flexible-adaptor/19914

[Old_Geezer]

It's a CDA Canopy hood CCA7SI.

(I was informed by the kitchen company that it would fit the canopy I had bought from them, that all the ones they sold would fit, but it was a nonsense. I spend ages cutting out the baseboard it had to fit into, only to have so little material left it collapsed under it's own weight and I've had to buy & use brackets to get it to stay.)

Yes that looks familiar save it is Manrose whilst my pack says Homebase Low Profile Ducting System.

That second one looks a possibility, thanks. Now not sure whether to risk buying the first in case it fits better (only to find it is exactly the same as the one I have). Decisions, decisions, decisions.

Thanks for the advice, it may be the solution I'm looking for.

[Old_Geezer]

Thought I'd update.

I went to a local Screwfix Saturday, knowing I'd have no time to use them until Monday earliest, and next Saturday probably. They only had one of the items. The fixed version they had no stock of !

Went into B&Q Sunday, they had ridiculously priced Manrose items. No single reducer but a bag containing two of different sizes. As I wasn't interested in buying I measured and noted the diameters of the smaller one. And noted it was labelled 125mm to 100mm. Which confused my as I thought the standard was 200mm. It did indeed have a 125mm internal diameter.

I now check the extractor paperwork, yes it says 120mm.

I check the packaging on the Homebase reducer, yes it says both 120mm to 100mm and 5 inches to 4 inches. I check it's diameter again, it is 125mm.

Then I see, TB, that you said it was a 125mm standard, I'd missed that point.

So the extractor isn't standard after all. Plus, the Homebase reducer has the wrong information on the packaging. (I may try to get a refund as it is no use to me.)

No wonder I was totally confused. And to top it all, as mentioned, I bought a length of 5" pipe and can see the reducer couldn't be used directly on it anyway. The pipe and reducer have exactly the same diameter and would need a coupling even if I had a use for it !

At some point I'll see if the rubber adjustable one works for me.

[Old_Geezer]

Darn I *HATE* the lack of editing facilities here. Just denied to make folk look a bunch of morons for all of time.

As I typed "Which confused me as I thought the standard was 120mm"

[Old_Geezer]

Not tried the rubber one yet, Saturday probably, but just realised something. (I'm unsure how I manage to miss so much these days.)

It is 120mm to 136mm, which means it will need to be tightened up a lot given that it's smallest diameter is the size of the largest diameter I need to fit.

I'll let folk know how it goes.

Never knew this was going to be so much of a problem. It's just an air vent after all.

[Old_Geezer]

As an indication on how fast the kitchen is progressing :-) Just checked that flexible one. Was a bit concerned as it would need to be tightened rather smaller than it was designed for, but it seems to do the job. No time to actually fit the extractor today, but fitted the pipework and it stayed on fine.

[Old_Geezer]

Not too sure why I'm updating this, except for completion.

It all became academic when I tried lifting everything into place. There was insufficient room for the reducers/adaptors. I'd have had to fill in the hole in the wall and cut it higher.

So I did the only thing I was left with, removed all the pipe/gubbins and just mounted the wall units. The extracted air has few other places to go save through the existing hole in the wall anyway. Disappointing though.