Nickfromwales

@Gorlando Best to start a new topic in 'house design' so this exchange doesn't get lost . Cheers.

Hi and welcome to the forum .

Seeing if the £2.6k down draught extractor actually works !?

Not suction . Sufficient airflow through the duct under flush 'flowing' condition. E.g. The equivalent air in to match the volume of water dropping. Can that happily be pulled through the duct IF that's the path it chooses to use to relieve the deficit.?

At the stated 25a breaker rating there may well be shunt resistance allowed in that. 1.5mm2 is good for 18a nominal so 2.5mm2 would be the minimum. C curve breaker is prob best too. The cable needs to exceed the current rating of the breaker so, if 25a, then 2.5mm2 is very close. That's shows an estimated 5750w peak threshold, but they've obviously allowed some headroom. Is the 3700w stated as running or peak ( shunt ) ? Remember that you should allow for over current as well as a short circuit. That's why I'd use 4mm. ?

That isn't cheating that's a good way out. FYI if your ever half inch short , a straight coupler and an M&F 90 into that will gain you the missing length.

I was going to brew some fresh coffee and keep at you, but just remembered I'm up at 6 to load the kids brekky into the catapult ? Nos Da!

What about with any mcb loaded board? Same thing Multi-RCD units still wipe out numerous circuits in one go. Can't really agree with that PoV TBH as I think they're a vast improvement. True circuit isolation can easily be achieved by knocking the isolator off imo, plus anyone messing around with this should examine the rcbo type before undertaking any work anyhoo. This could go on a bit

4mm if it were me. SY all the way for ease and uniformity.

I did. She didn't give two hoots

Spill the beans Harold. ? I don't see the advantage of DP TBH.

Thanks. My mate says hi.

Ah! Ok, Same room = oky-doky. Seems good to go. ? U/S sockets on a ring is plenty good enough TBH. Just going radial in mine so I can knock rooms off individually. Cable runs are a breeze too that way.

Yup. Doing my bedrooms all on radials. Work in progress . @Onoff will know what I mean. ?

A, er, friend of mine wanted to know what a Tony Tray is? Thought id ask, being a good mate and that

Often referred to as "night-latch" where it's partially open but the locks are still fully operational / secure.

Anyone actually know what brownie points are?

That should get you some brownie points .

This with a non-return valve so it stays dry. .

He can't, sorry, due to copyright laws I just made up

Let me save you the squabble. . Hep is just fantastic stuff. No matter if it's a 90 or a straight your talking fit and forget if youve assembled it accordingly ( rounded and de-burred copper and inserts where required ).

This is all the solution you need . Water so you'll see leaks straight away and just top it up with air to get your target pressure. Would it be better to bend copper in that corner and have straight connectors outboard ?

Any radials for fixed equipment I've ever put in have always been on either a 16a or a 20a breaker / rcbo and in 2.5mm2. The derating always got done at the termination point eg fused spur. There you select the fuse rating accordingly for the connected equipment. My choice here would be to install it so you can hook anything up later without worrying about loading. Fwiw I've never run a radial less than aforementioned, only ever deviating when it's outside lighting etc where I use 6a or 10a accordingly. Just can't see any point in running such a low powered radial unless you plan to run 2.5mm2 anyway ( which would leave you the option to upsize the breaker later on if so required ). I'm a bit old school that way tbh, but that's how I got taught as an apprentice spark with SWALEC. If your 101% sure it'll never be needed then take what I say with a pinch, but better to put it in now than later. Remember that you'll need a fused spur or a socket anyway ( so as to get localised fused connection at the termination point ) so not much more money tbh.

Make the boiler feed a 16amp x 2.5mm2 radial and fuse down at the termination point. 6a is too close to the wind imo, with due consideration being given to future proofing. Pennies difference so better to do now.