JohnMo

Only answer question they ask and only answer what the don't ask. Don't ramble on with this, that, or the other that isn't explicit in the question. Example of saying things not explicit asked for - reading this I am assuming your house is scheduled to fall down in the future, you most certainly don't mean that. So you should state "Surveyor's report states, that my house isn't going to fall down." Or better still don't mention anything - never seen a question that asks, is your house going to fall down? My house is an ICF build. Many insurance companies take that is a novel build method, but stripped back it's a concrete wall with insulation. So wall material is concrete, the fact that it's insulated is a given (it has to be to comply with building regs). Surrounded by trees, understand what sort of tree they are, a beech tree has tap roots, so are unlikely to affect a house, no matter how close they are, other species can be very damaging. We have 30m tall trees within 20m distance from the house, but the question asked was within 5m, so answer was no. Your SIP build is likely to have a concrete block skin, the fact your insulation is sandwiched between OSB is neither here nor there, your walls are concrete blocks. Roofs are in the general states (natural material) or tiles (stuff like concrete. Most houses in UK are tiles, so nothing novel there.

Mine is also 400mm from walls at back and side and 500mm for the maintenance access side. So that looks like it needs fixing The other thing I would change is the MVHR in out arrangements, would installed a combined flow in extract out grille and position as high up the wall as possible. Then both elements of the MVHR can have a good distance from the ASHP Grille such as this https://www.paulheatrecovery.co.uk/product/200mm-directional-external-combi-grille-for-mvhr-black/

22-09 electric chart would certainly indicate short cycling almost all day. So as you say trying to keep a small buffer happy isn't working. But everything I stated are the reason for the cycling. Mentioned above by @HughF was that the buffer has no control system or feedback. So firing the compressor based on return temperature most likely. Cosy tariff - Would certainly look to dump the buffer in the short to medium term, convert to volumiser on the return side, remove secondary side pump(s). This can be done with or without buffer - either run pure WC (so call for heat 24/7) or a time based running in Cosy periods with WC flow temperature (maybe slightly elevated to compensate for some off periods). Set thermostat so you have no call for heat during really expensive period. Then set thermostat to 23 in cheap periods and a more tolerant temp in normal rate periods, say 19.5. This would encourage most running in cheap periods, coast in normal rate off in expensive rates, but internal temps could swing about if on radiators, less so on UFH. Ideally if you can run a second setpoint that would be better than a thermostat set point. I have (but don't currently use) a second set point setup, this add 5 degs to normal WC curve, so this would allow running elevated temps in cheap periods and normal WC at all other times. Net result is runs hard during cheap periods, pretty much off for several hours. Observation - the intermittent running to keep buffer happy is possibly costing as much as it would to run WC 24/7, as to run intermittently via time control, you have to run a higher flow temperature. Plus running WC allows you generally have a cooler house and still be comfortable. So current operating strategy is costing you not saving you money.

Short cycling occurs when the heat source cannot get the heat away quick enough, or there is little or no demand, or flow rate is too low, or all three conditions. As the heat source goes through a start cycle the target temperature is exceeded by enough margin to cause the heat source to shut down, this repeats. To eliminate it, you can raise the target flow temp, add a couple degrees to the existing target temp. Then fine tune down. Or increase the system volume or flow rate. If you have the parameter available you can increase/decrease the PI integral time. This changes the reaction time of the controller. The way your system is setup can actually cause short cycling. If I run heat pump, so the circulation pump runs periodically, the temperature of the water close to the heat pump cools quicker than that inside the house, so heat pump thinks it needs to start up, but in reality it doesn't, heat pump starts, the warm water from house hits the heat pump it shutdown. This is fixed by running the heat pumping it's default mode of circulation when there is a demand for heat. The heat pump control then knows exactly when to restart - no short cycling.

Just keep installing them buffers and thermostats, if you want. But alternatives exist. I will sign out now.

Not exactly true if you run an open single zone system as no heat.is wasted. But you do need the pipes that go to the cylinder insulated. With an ASHP that normally needs a buffer to get acceptable flow and cycle times, but also leads to less than ideal CoP due to flow temperature distortion, unless the buffer is huge and the flow through primary and secondary is perfectly matched, which it will not be.

Didn't you ask about this back in June as well? You just need something like this https://www.bes.co.uk/primary-pro-ashp-insulation-28-x-19mm-x-1m-26208/

They are talking out their ar** All outside pipes need insulation. The insulation needs to be 19mm thick minimum, ideally 25mm and UV resistant.

What a load of ****. So a typical heat pump draws 8kW from the grid? The typical house in the UK only needs 6kW of heat so running a CoP of 3 that's 2kW - but more likely 1 to 2kW. This country loves to waste money.

Build a bunker - not house Diesel generator and an oil boiler tank to feed it.

5 gallon jerry can, would keep generator running a few days, running full time. But you wouldn't run while you were asleep or out and about, only when needed. The fuel doesn't go off in sealed container. So why an issue?

Carbon steel structures normally have a 3mm corrosion allowance. How quick the steel corrodes really depends on how you do corrosion prevention. And how damaging the environment is to the corrosion prevention and then the parent material. Is 2mm suitable? 100mm dia, I would be looking more like 6mm and then hot dip galvanised and not bother with the faff of concrete or gravel.

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