Nickfromwales

In that case, the shorter tray is a BIG mistake.

Poor design of the running gear if it can’t retain the chuffing lubricant! 6 months for a full window MOT is a real PITA. I could understand with big sliders, but not with windows / regular doors etc.

Did you intend putting a shower door on here?

Problem here is that the block & beam floor will need to be SLC'd before the floor is anywhere near uniform enough to do away with a screed.

Concrete or "dry" screed? If you get stuck, you can try my guy. You'll just need to be ringing sooner than later with ANY contractor atm as the norm is 8-12 weeks minimum lead time with anyone decent at their job. Defo 2 wagons with that quantity if dry screed, especially if it turns out to be a warm / hot day.

Biggest culprit is the generation meter having been cabled arse-backwards. If your confident, turn off all isolators (after sundown) and take the cover off the meter. Send some pics and tell us which cables are from solar and which are from the CU.

It's 2023 mate. £5 P&P and I could be eating that after my lunch tomorrow.

You have manual levers on the valves so you can manually operate them for filling and draining, but for them to be used (with just a 13a plug if you want) that's fine, just you MUST energise these so they open 100%. The manual levers only open them around 10-15% ergo you'll have shit flow through them. You're going with the valves. Don't make me come down there 💪.

Not a sensible choice, as you’ll be paying more than the price of the valves in another visit. Plus, it may as well only be drained down once. Go without food, buy the valves. Simples!

I just quickly amended the link, as I first linked a 3 wire unit and you need a 5 wire unit(s). That link is sound if you want to order these. Cheaper than the PlumbingSuperstore (AKA JTM Plumbing) too!!

https://www.screwfix.com/p/honeywell-home-v4043h1106-u-2-port-motorised-valve-28mm-28mm-compression/40705?tc=ET2&ds_rl=1249404&gclid=Cj0KCQjwj_ajBhCqARIsAA37s0yvv53xnxJzJUITu9KDNeych3N2aLa6BFjubSNJxYbxeE5-ZmBygvUaAsP7EALw_wcB&gclsrc=aw.ds I think your pipework is 28mm, just check to see if it reduces after the first manifold and goes down to 22mm. If so, adjust to the second ZV being 22mm not 28mm. You can put the both where the 28's T off so all your wiring is local to the first pump / first manifold, eg the second ZV doesn't need to be at the second manifold (so no running of more cables for no reason) Tell your guys about the planned inclusion of the ZV's, as it will provoke a little tweak of the wiring, plus the inclusion of 2x wireless stats (if you want to get them fitted now it would probably be more economical for them to nut this in one sitting vs multiple visits / retrospectively adding them).

Just insist on a 2-port motorised zone valve being fitted to each manifold, as they can be connected to room stats and you can at least turn one off whilst the other still runs etc, but not without zone valves on each manifold.

In a nutshell.

Yup. I never design like this, especially if it’s over different floors in the same heated envelope. Your guys are relying solely on the ASHP to maintain the global flow temp which is the temp that each floor then receives. Hopefully they won’t act too differently,

Nope. That blending set isn’t suitable for flow temps sub 30°C. Do not install that. The one I linked goes accurately down to 20°C.

I’m just unsure how the different sections of the house will each behave, if they are sent one flow temp. You’d typically be running much cooler temps in upstairs (GF) vs the basement which may require higher flow temps to meet the same ambient. Just seems a bit indiscriminate to me, but could all work perfectly by ‘accident’ or design.

Manifold + blender + pump? Or buffer > pump > manifold with no temp control? I use these LINK

Depends on the size of the aggregate I suppose, as the float will just roll over them if they're bigger than the gap. Just take some measurements from datum timbers set into the ground outside of the slab and you'll not struggle to find them afterwards, then you can make them an inch lower than TOC to guarantee the power-float can whizz over them. Take lots of pics / measurements You go and pick these out whilst the floated concrete is 'green', like literally as soon as you can walk on it.

I assume you’re putting straight couplers onto each, and then the blank plug goes into that just below the surface?

Happy days! Just go with the concrete as anything else will be noisy to walk up / down on. The builder will need to shutter each step, but also to affix (with a gas nailer most prob) something like Expamet LINK to ensure the concrete stays in situ. Priming with neat SBR will help too.

Not quite! Just go buy a box of PB screws and screw one in every 150-180mm and do that along each joist. DIY job tbh, and you'll know it's done correctly then. Then just fill each one and get the decorator to sand back and paint again. May as well just yank off the band-aid and deal with this once.

Yes, but you'll then just get a dot of light, if that's ok?

Usually a min dispersion of 24° or 36°.