Nickfromwales

In terms of sign off, the GSR chap will look for 18.5mbar or above ( check the MIs of the appliance you select ) and that’s with the hot water tap fully open and the boiler going at 100% burner rate. The supply from the street is fine for a bigger meter, that’s all you’d need tbh. Combi kW ratings have zilch to do with heating, as that usually takes <12kW even in a poor dwelling, and specifically relates to the devices capability to produce DHW.

Yup. With today’s water bylaws, most taps / other outlets are flow governed by manufacture, so a 22mm feed is pointless. Also, unless this is a monster heat store combi, the cold inlet will be 15mm, so another reason to not employ 22mm hot pipework

You do not want to upsize the hot water pipe. You’ll massively increase the delay in getting hot water out of basin / sink taps. 👎

FWIW, I’m on a TF house atm, with 300mm glulams and I got permission for pre determined / agreed location etc 96mm holes. Can be up to a 1/3 of the depth dependant on thickness of wood.

Structural engineers can help you decide where to drill that number of holes. You should be fine, don’t go to the expense and ugliness of boxing in etc 👎. You can stop the insulation ( if it’s actually required ) either side of the joist to make the holes smaller. What is the 22mm feeding? Not hot water?

+1

I doubt they’re massive tbh, so I’d stop worrying about that and look at practicality. Go with the garage, as when converted to AC all you “need” to do is upsize the cable to combat any losses vs distance. Say upgrade from a 4mm2 cable to a 6mm2 cable for eg. Done jobs where we’ve run the AC for 135m ( ground mounted PV with external inverter ) and was still performing extremely well as we upsized the SWA back to the CU. I think you’re over thinking a little. It’s all within the footprint of a single domestic dwelling so afaic you can relax a little and just apply a little sensible mitigation to get the best result from a practical installation

OK, firstly.... 350mm of XPS? Secondly.... Which ICF system is this? Woodcrete / EPS ?

Space a plenty, speak on Obi Wan........

That’s what I’ve been thinking for some time….. Header tank is way too small, so when low the splashing water from the fill valve stirs up the sediment. Extra Radox is recommended lol.

Heat circuit input connections to the cylinder just look too close together…….

I’ll need a pint in my hand before replying to this later. In the interim, is there 100% defo just the one header tank servicing the copper cylinder and Rayburn? Looks like it from the images, which send a shiver down the spine…….

There will be plenty of large car and HGV batteries around for the next 10 years at least. I’ll worry about that again after the first 10 years has expired. Not lithium no. Regular car batteries. Cheap and plentiful in the used market.

If going for the Tesla tariff then export is defo required That’s why they give you this “deal” isn’t it? So they can suck ‘em dry as quick as you can fill ‘em. 50% of 48kWh is still a bloody decent bit of storage for a domestic setting. Most decent size dwellings where we’ve installed PV plus batteries have had a 9.6kWh and that’s often difficult to routinely fill and empty ( by themselves ) every 24 hours. With the multiple hybrid(s) you also get the benefit of huge rates of discharge, plus instantaneous UPS to boot. Would piss me off to be having peaks of consumption that called for support from the grid, when there’s perfectly good stored energy in the batts. Cheap as chips for the sizing, zero export capable out of the box, so what’s there not to like? Yes, you’ll need a bit of room to fit the batteries, which to most will look “unsightly”, but I think my electricity bill is unsightly, so my minds made up. “Death to grid dependency”.

I thought it was only me that only opened their mouth to change feet 🤣

In a nutshell, yes, so minimising the capital cost is of paramount importance if you want to even glance at breakeven / RoI numbers Folk need to remember that charging off excess and then using it of an evening is a relatively easy life for a battery system. Change the scenario to where you sign up for the Tesla / Octopus arrangement and your batter is in for a kicking, thus further reducing its useful lifespan ( can drop to 7 years of 'usefulness' vs 10 with the right amount of abuse. I'd be interested to hear what the warranty wording is like for that system in that arrangement, as they benefit from beating the shite out of the system you paid for.........and then own.........and have to maintain / repair / replace....... @Wil I'm waiting to get a reply from a supplier for an Iconica hybrid inverter ( 11kW ) which is sub £1500, and then I can open my horizons to which battery I choose to employ ( within the manufacturers recommended connectable equipment options of course ) but I am also looking at BMS options to charge near end-of-life commercial vehicle batteries. Cheap option, with fleas that come with the dog ( monitoring / replacement etc ) but the costs should be vastly cheaper. All depends if you want a nice looking shiny box that someone fits for you, or if you want to ( and are able to ) get your hands dirty with a bit more of a bespoke setup. Pointless doing anything unless its really worth doing tbh. Change of £9k before VAT........ https://www.photonicuniverse.com/en/catalog/full/566-20kW-Zero-Transfer-Uninterrupted-Power-Supply-UPS-System-with-48kWh-energy-storage.html

I've seen a YT video with some Tesla do-dah that connects to your CU after 5 seconds of grid 'absence'. Not sure what it was called, but Robert Llewelyn has one in his garage. "Fully Charged" was the channel.

I’ll post some links when I get to narrow down a supplier with stock!! Photonic Universe is one contender. Prices are just a google search tbh. Just as the cells are at the end of their life because of the excessive cycling to get TO those figures……..,

Words of wisdom.

If you’ve put screws in, then prob not much coverage left to put scrim and skim atop the screw heads. With screws into ply, I doubt you need to go any further 👌

Factor in the date the batteries will expire That throws it further off again. Im just about to pull the trigger on an 11,000w Iconica hybrid inverter ( 2x5500w strings ) and will then bolt on 9.6kw of AGM batteries and run for a year, with a view to adding probably the same again in battery size.

Sounds like the air hadn’t been bled out of the upstairs heating properly? Turn all the rads off except the one nearest the heat source, bleed that rad and top up the pressure, then see if that rad gets warm / hot.

£400 a day for spraying and washing their hands of all the ACTUAL work would have been a piss-take tbh. Good for you getting your hands dirty

Yup, as long as it has a copper overflow and copper ( metal ) connected pipework. This bit is confusing me. Gravity primary's normally convey heated primary water to a coil in a DHW cylinder, been that way since I was knee-high to a grasshopper. How many tanks are in the attic? Are these both fibreglass? One for the CH circuit of the Rayburn, and a second exclusively servicing DHW? How many connections ( and where ) on the copper DHW cylinder atm? Need to understand this a bit better, but tbh mostly out of curiosity if things are to be changed around anyhoo. A 'circuit' will be a victim of circumstance, so no generic yes/no there If a circuit has UFH and stainless / copper parts the corrosion issue is miniscule, if rads are present the issue is increased, albeit still manageable with inhibitors etc. If folk are bathing in DHW from a primatic cylinder you cannot treat the primary water so must upscale on design / diligence, but if your DHW and the CH primary water re two completely separate bodies of water ( suggested by the 'plural' reference to the header tanks ) then there are options for chemically treating the water to better manage condition. A magnetic filter would be an obvious friend to introduce here, but it would need cleaning out regularly for the first year. You don't really want to introduce a sealed and pressurised setup here, IMHO, as the folks will have to monitor / top up / make sure they don't over-pressurise etc etc, aka ball-ache. F&E = simple life / minimum routine maintenance. If the F&E tanks remain in the attic ( which they very likely will have to ) then you're fine to stay on gravity, so one less problem. Upstairs heating stays on that too so, so happy days. So; Bathing still to be off electric showers? Ergo stored DHW will be for washing hands / dishes etc only? Seems madness to me, especially if 'religious' Rayburn usage is on the cards for the foreseeable? Remember that occupancy by anyone deemed infirm requires thermostatic control for anti-scald, so regular electric showers 'should' be changed, for both safety and comfort, ( if being retained ). What will happen the the second heat exchanger connections? The ones doing DHW via the steel tank? Te Rayburn is a 4-pipe setup atm yes?

+1 to Torbecks, plus they fill silently.