JohnMo

So give it another 10 years they maybe paying European prices, my heart bleeds for them. They don't have to consume so much electricity - forgot they need a huge walk-in fridge for all the food they buy at Costco and Walmart, because it's so expensive.

Get prices from them and others, pretty sure their service doesn't come free.

For the small uplift in AC coupled battery cost, why would you add the extra complication to just let your house limp? I get the full 6kW available from inverter plus what ever PV is generating. So heat pump runs, can cook the tea etc. power cut just go unnoticed.

But a normal car isn't, it's a V8 truck. Everything is cheap, so why would the normal person care. Electric is between 15 and 17 cents per kWh, so well under half what we pay?

That's what I liked about the GivEnergy AIO, once you find a home for the gateway, it does it all out the box, no house changes needed.

That's what side lights are for, ours just switch on from a normal light switch - nothing like saying hold on a sec, while I get my phone out, need to reprogram the lights, it's a bit bright - moment lost - you will stay single for ever. No down lights in living room you don't need them, we have 8 up/down wall lights than never get used, and a couple of side lights that are used daily and that's in a room with 6m high high vaulted ceiling and about 38m². The only down lights we installed are about 120 to 150mm dia (depending on room), kitchen/diner has a whopping six of them. Nice even light across the whole room no shadows. 50mm downlights cast a narrow beam of light, so worth considering and the main reasons we did the polar opposite.

Does your inverter with the battery, not supply the house in a power cut? We went AC coupled for that reason, grid off makes no difference, house runs as normal, PV string inverters don't see and difference so keep producing. We also have a geny with change over switch should battery run flat - need to get more petrol.

So how efficient is it running several miles of cable to the 80+ fitting? The 80+ light fittings isn't efficient either! That may look on paper, but isn't suitable for a property that has to last several life times - not mechanically strong enough. 80+ fitting your house must be huge to need that many, that's more than twice what we have (200m²)! Or are you going for an 80s show house vibe, with way too many down lights? Think you may need your head testing, too long thinking without real feedback - the problem of living alone. We had a house many years ago with dimmable lights, twiddled with once or twice, than thought what a load of sh!te. Never bothered again, nor will I in the future, nothing much to go wrong with a couple of light switches - one does side lights the other main lights - flick on once and off once per day. Our whole house wiring cost less than you will end up spending on just lights, so you twiddle a few settings then get bored.

Maybe weight? Our doors are also double glazed, I chose to go double with Krypton gas fill instead of Argon. Brought the whole door U value down to 1.0. Really good door otherwise was 1.2 with Argon. think triple glazed was something like 0.8 for a door. (from memory, exact figures may be a little different - but not much). You could go vacuum double glazed for better than triple, but cost starts to get a bit silly.

Not always, really depends what industry you are discussing, as many industries or even manufacturers describe bolts and screws to be different things although talking about exactly the same thing. The meaning changes between countries. When I went through my aviation training I was given very specific training on what a bolt and screw were and then in the oil and gas industry the terms were mixed and not very specific. A write up here https://www.accu.co.uk/p/131-difference-between-screws-and-bolts

Yes, it isn't fully threaded it has a plain shank section, so technically a bolt.

Really depends doesn't it, if you paying a huge premium to the get the £7500, it's not really 7,500 All in I was less than £3k, fully installed, without taking any tax payers money. Win for me and the tax payer. Plus no one poking about my house that acts like this

Amazing what you can find down a visual image search 300125_01_17.pdf fifm_rev.3.0.pdf

Very large farmers sheds and buildings go up all the time, bet none of it has any local authority permissions, does anyone care - no

We never bothered with build insurance, but when we moved in work was still ongoing. Set up building and contents insurance in the normal way and ticked the box for work happening currently on site and then listed the minor and bigger jobs to finish. Didn't mention completion certificate as it wasn't asked - only answered the questions that came up truthfully. We are over 50% for timber cladding, no-one asked about it!

Another good reason to avoid MCS.

Or you can always go AC coupled instead.

There are a couple of things that maintain water pressure. No leaks, and an expansion vessel. Water contracts as it is cooled and expands as it's heated. Depending on system volume, the volume change when heated and cooled could be a reasonable amount. Setting and sizing the expansion vessel and system pressure is important. Your expansion vessel needs to be pressured with the system flat with zero pressure (or at least the leg with expansion vessel in it). You need charge to the correct pressure for the system set pressure. If you set the pressure too low or the vessel is too small every time you go into cooling mode your system pressure is likely to drop to zero.

If doing new cylinder, just do one with a big coil, less to go wrong, one less pump to run less for installer to do

Why wouldn't you have them in ANY house. Bonkers not too. MVHR is just a ventilation tool, not some magic bullet.

Just choose a direction and sticks with it. Left to right for all rooms and halls or up down for all. I prefer them running from windows instead of across the main windows, so my case all would run left to right.

It is, but heat pump cylinder or a normal cylinder has to sized per MCS guide lines. BUS just states heated by a heat pump, doesn't mean it can only be heated by one heat pump at the property. Only thing with integrated heat pump cylinders is they generally have a long recovery time, due to the dinky heat pump they use

Two schools of thought, one lag everything, the other lag nothing. But your best to lag everything that goes to DHW, so you are not adding heat to house during summer. The lag nothing, comes from, with an ASHP, the ideal for good CoP is to run WC and a single zone fully open system. So what is the pipe insulation doing, everywhere in the house, the voids etc are also at a similar temp to rooms. Obviously if you don't run the heat pump like just described, insulation needs added to all pipes. Anything outside the heated envelope insulated to death in both cases.

You will now storing DHW at 50 or below, what do you currently store at? But plate heat exchanger would be able to heat cylinder, the current coil wouldn't be used any more. You need to concider defrost cycling, this will bring down the 10kW quite a bit. There was some testing done on a Vaillant ASHP and the conclusion was the 7kW output in a UK setting was correct, the datasheet was ok for mid European location, where defrost isn't so much of an issue.

If that price after grant, a rip off from what you say. That is a fair comment - add another DHW heat in the afternoon, it will have lost the battle and you will have a cold house and large energy draw at the end. You need to size ASHP based on how many hours you are heating DHW (3x 90 mins), so 4.5 hours. Take that away from 24 hrs. So you now have 19.5 hours to provide 24 hrs of heating. So (7kW x 24 hrs) / 19.5 hours, so heat pump size minimum is 8.6kW at your design outside temperature. So realistically you are looking at a 9 or 10kW heat pump.