Nickfromwales

So, the “NRV” is a bypass valve and not an NRV in this instance? Removing this or allowing flow through it can only take away from the pump energy pushing water around the loops, so a bit lost as to how this will promote flow ( even if it has ! ). Most bypass valves are user-adjustable so they can be ‘slackened off’ to allow them to operate at a lower resistance. Was this one not adjustable?

CT1 on the deck is plenty, as long as a proper and robust metal wall profile has been used. Do NOT ever dream of doing away with the wall profile ?. 8mm at that length of screen would benefit from a top stay bar, 10mm probably good without it. That’s said…..( here comes the caveat )……. if it’s a regular domestic setting. You have to include the much higher likelihood of someone using this and taking a tumble, plus that likelihood increasing over time / use, so you should factor that in now for maximum safety. That assumed, I would say to fit a top stay bar now, perpendicular to the glass at the 2/3rds point to be safe.

The tank stat option will likely be too crude as a control, due no linear hysteresis, and result in under / over-shoot IMO.

You just re-fit the LS>LR link to use bus only.

Does it not have a regular stat connection as well as the bus connection? Have you checked the Mi’s?

Nudura all the way. Woodcrete systems are porous so moisture ( rainwater ) infiltration is a huge problem all they way up to the external rain screen ( render / other ) being installed, plus soffits - facias - gutters being on and functional. Having had 3 M&E projects run simultaneously, with 3 different types of ICF, I would say hands down that an EPS ( inherently water resistant / non-hygroscopic ) based block would be my first choice. @Russell griffiths recent AT score of 0.28 with a DIY Nudura build speaks volumes. That was with an untreated internal surface, just the raw blocks and concrete core plus perimeter / junctions / openings sealed with various tapes & mastics and foam etc, but most importantly bone dry from the moment the roof was on, including driving rain etc for over a year going directly onto the external EPS facades. That allows the inside to be bone dry and pushed on through the worst parts of the year unhindered. A huge bonus. Plus very little to nothing to be done internally to get airtight, which cannot be said of the 3 big names in woodcrete ICF. Agenda and budget plus your skill set will be big influencers in which product you end up going with.

Get a new builder immediately!!!!!! 50mm of insulation is not even building regs, so this chap is WAYYYYYYY behind the times and not up to the task. If you put anything less than 140-150mm of insulation under a HEATED floor, you're going to have very poor results with the heat output, plus the running costs will be very high. I would also have a guess that the other aspects of the building are leaky and poorly insulated, so the space heating demand will be adversely high. That is not well suited to UFH as it runs at very low temps and cannot be turned up beyond 27oC floor surface temp without the home becoming uncomfortable. This sounds like a disaster unfolding, sorry, but good you have registered here and are asking the right questions Stop this work now, before it's too late to change it.

Hi. Yes, as long as the coils are 230VAC rated then you’re propel is sound. Just be sure to have good segregation of the cables at the relays, so you cannot ever get 230VAC going down the zero volt side.

I was once tempted away from Uniquity WAP’s by a HA company, as they were adamant that Ruckus were a far better device ( at roughly £2x ) but with all of the Ubiquity stuff I’ve installed for clients ( who do not / will not tolerate poor performance / unreliability etc ) has performed way above my expectations. I particularly liked one version of their wall mounted AP which has a data throughput socket at the base of the unit. That allowed the 1x Cat6 cable to support the AP but also give an additional data outlet to connect a hard-wired bit of kit to, gleaned off that AP. If you have for eg a PC in situ now, plugged into a Cat6 outlet, you could buy this AP and connect the PC back to it whilst creating a WAP point in that location. If it’s not a PoE point now, just use the supplied PoE injector to get the power source for the AP and you’re up and running. I’m very happy with ubiquity to date, and just bought a couple of the long range ( not Lite ) AP’s for my own place. Buckets of WiFi off them.

I never put push of it into compression, as it’s a plastic pipe which a metal olive then bites down into. Insert just makes the plastic pipe stay rigid, and does nothing to prevent the olive sinking into the plastic. Never ever done this on a plumbing job, unless it was a temporary setup like a filling loop etc that I needed to cobble together in a rush which I then babysat whilst in use. I would never do this as a permanent job, and recommend the use of a push fit fitting into copper pipe for every single instance where you need to transition from compression to push fit.

I use those a lot. Very robust and reliable, and a perfect partner with Hep2o ( Wavin - Hepworth ) pipework.

Was referring to the OP not your build. ICF as above. 5kw will suffice regardless of DHW consumption, as you’d just size the UVC a lot bigger and accept longer recovery times. No ASHP can replenish DHW linear to it being consumed, so the point is academic to be fair. But it would work, just slowly. It would only be 1kw behind a direct UVC with 2x 3kW immersions.

Be interesting to hear what the installed cost is for a typical GSHP with a borehole, fitted and finished….

And put a couple of small desk fans in there, running 24/7 and oscillating, to keep the air from stagnating under the units.

A little 5kw ASHP would suffice, if a big enough hot water tank was fitted, and the heating load was equal to or lesser than, it would simply take much longer to recover after depletion. Why a GSHP? Seems a massive ball-ache and no support from RHI = big capital costs and a far longer break-even period. ASHP seems far more practical and attractive for a number of reasons. Forget solar thermal, go for more solar PV as ST is a PITA to own and maintain, has significant losses, and is a one-trick pony. PV can be converted to heat with an immersion, and when the tank is satisfied the excess electricity can go towards the house base loads. ST just heats and heats, and then carries on doing that all summer which is of little or no use if you're not there to keep drawing off DHW. Needing bags of DHW is not necessarily managed by the heat source, more the hot water device, so the position of the horse and the cart may need a bit of adjusting here

BRegs give stated max lengths for ‘small bore’ waste runs, iirc max length 3m before upsizing to next pipe diameter etc. For showers I never run anything less than 50mm, as the air break in that size pipe allows free flow from the bubbles / foam creating an air lock, which happens in 40mm. The difference is quite significant tbh, where the water etc travels in the lower half of the pipe and air is free to travel over the top keeping things flowing very well. Its an odd phenomenon but it makes a big difference in my experience. Smaller pipes do slowly clog up from the soap etc coating the inside of the pipe, layer by layer, over many years of use. 32mm waste pipes from basins and 40mm waste pipes from kitchen sinks are the ones that suffer most, with pipes eventually blocking completely. What is found in the cut out sections of pipe are evidence of this. Quite unbelievable how bad they get. If you are burying / boxing any of this then upside by 1 in every instance. 40mm replaces 32mm - 50mm replaces 40mm etc. For wash basins I run 40mm up vertically and fit a 40mm bend with a 40x32mm reducer in it to come horizontally into 32mm pipe and then to the trap of the basin. Makes a huge difference in discharging water away from the basin.

The coffin tanks are quite quiet tbh, as the full valve usually do no more than 4 lpm flow rate. That plus the water drops down inside a plastic sock so there’s no sound of water splashing into the part empty tank. If boxed in a bedroom and wrapped in 100mm acoustic insulation they are perfectly tolerable in fairness.

You're fine, other than the obvious lack of hands on electrical skills.... Touching neutral or live to earth with the RCD on and the MCB off will inevitably ( nuisance ) trip the RCD. That's normal / expected, so nothing to worry about there. Yes, isolate the live, neutral and earth wires from the rose to the pull-cord and that's you done in terms of electrical isolation / making the pull-cord and fan safe for removal. FYI you should not be testing continuity with cables connected, as that can yield misleading results.

Triton T80Si Pumped

Have you a garage or an outbuilding / lean-to? You'll need somewhere to install a cold mains accumulator which will be the size of a typical UVC. You'll need to convert one or both showers to electric, or upgrade the combi to a heat-store combi. You'll not be getting off the hook easily here I'm afraid, as you cannot run 2 showers in an HMO whilst guaranteeing that a 3rd person won't go and wash the dishes or put the washing on etc which would then kill the showers on the spot. A bit of upheaval is unavoidable, if you wish to go HMO.

Not without the MCS, as I said, read my way = no payment for export so net metering is out of the OP’s equation…..unless I’m missing something?

@joth

Err, if a single phase inverter feeds into one of there phases, how would the PV generation get to ph-2 and ph-3 without that methodology?

It’s obvious from the first few posts that the OP is being sent in that direction. Any mention of a 3-ph inverter would obviously require a 3-ph CU.

It needs to be insulated ( rock wool down into the 110mm pipe will suffice ) plus pipe insulation over the pipe, if it’s less than 750mm ( iirc ) inboard from an outside wall.