Nickfromwales

I meant after survey and the resultant ‘correct’ installation.

It is the worst, sack of shit advice, any manufacturer could have given anyone. Categorically avoid doing this, please. If Hepworth has a bad point, it’s in giving that bit of naff information. They’d do a LOT better just posting a link to the fitting I showed you. 🙄

Pulling cold in from outside via draughts / trickle vents in winter = bad idea.

https://www.screwfix.com/p/hep2o-plastic-push-fit-adapting-male-coupler-15mm-x-/5970F?kpid=5970F&ds_kid=92700055281954514&ds_rl=1249404&gclid=EAIaIQobChMIvdOO8-DB-AIVkmDmCh2yTQeaEAQYASABEgL_uPD_BwE&gclsrc=aw.ds

Because you cannot put plastic pipe into compression fittings. You could however use Hep2O 1/2” or 3/4” BSP male / female fittings which accept Hep2O pipe directly.

Normally a couple of bends and then copper tails projecting out at 150mm c’s is fine. For a bar mixer you’ll need a fast / easy fit kit to mount the shower with, as with this approach h you’ll be binning the supplied cranked 1/2”x3/4” fittings. LINK

At 28oC I’d be looking to kill someone. At 25oC I’d be looking for A/C. You don’t know an old lady I once fitted a new boiler for, do you?

Would need to be holy water for you ya heathen 🤣.

Water?

Installed prices are quite significant either way tbh, so if paying for the whole shabang you may as well have the best item installed if the install costs are roughly the same anyhoo. I’ve fitted Panasonic and am very happy with them, also.

https://www.elementshop.co.uk/prowarm-aluminium-spreader-plate-390mm-x-1000mm-with-150mm-centres-bulk-buy-1-to-9?gclid=EAIaIQobChMI987eh4W8-AIVFIBQBh0pnw6NEAQYASABEgL-MfD_BwE

A layer of PIR directly under spreader plates ( set out meticulously so as to make the plates very slightly distended eg for excellent surface to surface contact with the P5 ) will add to the mineral wool and pay huge dividends. The wood fibre could be used instead, but if it were my house I’d use PIR for the uplift in the performance credentials. Yes, already noted, Sherlock 🤪. Just saying the underside of the heated pug tray would be only protected by the wool and also subject to ventilation heat loss from the free air movement in those underfloor voids. Thus, the PIR, sealed and made draught-proof, would ( should ) be a minimum spec under the pug tray. Prob struggle to get 25mm under unless the tray bottom was 11mm ply and in-filled with PIR before loading with the pug mix. Wool > PIR > spreader plates c/w 3x16mm pipes per tray / void > 22mm P5 > 6mm ply > floor covering = 👌

I'm not a fan tbh, as the vulnerable external mitres take a bash from hoovers etc and start to fray. Pine is much more robust imho, just a total PITA for prep / prime / paint. Get set up ( either way ) to spray all of these BEFORE installation, as this removes a ton of downstream backache and cutting in.

The're about to install one via me for my current full M&E package clients. Defo Rolls Royce, Bugatti even, but very good credentials for when it needs to count and boasts a CoP of 6 if installed to their ( very fussy ) criterium. CVCsystems also design and specify for my MVHR stuff, and Nick Vaisey is their in-house passive guru who is extremely helpful. Vitor is the ASHP guy, and he has also been very helpful in coordinating the above SE ASHP installation. Thoroughly recommend you talking to these guys.

That pipe will last longer than us mate

Yup. The caveat is that using up the depth of the floor joist means a diminishing space for a high-performance ( or indeed any other ) insulation under the pug screed. Needs a bit more thought Why not fill the depth of the joist space with the best possible insulation, atop the wool product, as a secondary higher ( highest ) performing insulation layer and THEN you can go for a 22mm P5 deck board minus the troughs. 6mm ply on that and you're sorted.

You will still need to insulate if this is less than 300mm from the perimeter of the foundations. Rockwool plus 25mm wall pipe lagging will suffice. Exp foam is fine with MDPE btw Just spray a little water into the 110mm pipe before applying to help it cure / expand.

The mention of "Landlord" suggests a rental? If so, raise these concerns with the property owner and allow the installer and the person who paid for the work to be do ne to discuss this between themselves would be the 'correct' path here. As far as the reasons for boarding, if this is a high / multiple occupancy building / flats over flats etc, then the boarding would ( could ) be a fire / smoke barrier and therefore it's installation would ( should then ) have been overseen / inspected by a BCO for correct execution and integrity. As for nails left sticking out to the point they are damaging the LVT flooring, that is just shite workmanship. If you're renting this is not really a matter for forum-folk, more for you to take up independently with the person you pay the rent to.

Not relevant, as this is heating which has always used circulation pumps. Gravity has been for feed and expansion only.

I very rarely test a domestic system like that. District often has 100’s of m’s of pipe in a linear run so it’s part of the installation guidelines. For domestic a blast with the cold mains ( typically around 2-4bar average ) will be more than suffice. Domestic never sees north of 5bar tbh.

Why test at 10bar? 1-3 is average, over 5-6 you’ll need a PRedV to drop it to 4. Just hook up to the cold mains and use that?

Don't worry, we'll learn you good, Jethro

Have you allowed for the restriction of the outlet that each pipe terminated into? VS what will come out of the end of the pipe? All completely academic imho, as larger pipes / higher dynamic flow rates etc are all arrested by the outlet and its governed output rate as set by the European standards for the max typical flow rates ( in line with water consumption regs ). The gross variables involved make this nigh-on incalculable afaic. The flow rates will all shift the second another outlet is opened elsewhere too, so further reducing the dynamic flow rates. For actual real world experiences, I have done multiple 10mm and 15mm radial whole of house installations, with pipe runs up to and beyond 30m, and there are no real world issues at all. Either install a HRC or just wait. As for filling a basin, you simply start shaving BEFORE the basin is full Simples!! Too much maths here, and I genuinely fear you're worry over nothing.

Don't panic about the fittings as Hep2o stuff is simply bombproof. Defo avoid doing that

MVHR + FCU's. Scrap the idea of the 40mm pipe to outside, that's mental. Route as you say to the cloakroom waste and run it all in 21.5mm condensate pipe as there will be only a thimble full of water going down the pipe at worst. You can mount the pipe off the true vertical rise eg so any drip where the pipe goes from 1st floor horizontal to the vertical drop cannot give you a drip-drip noise, simply by installing it 2 pipe widths off vertical so the water droplets ( even though.......... ........is typically correct ) cannot fall the full length of the pipe, as you certainly would hear a drip of water falling 1 storey and hitting the pipe again where it returned to horizontal at the cloakroom.