markocosic

The dumb mechanical valves setting flow through radiators and the dumb UFH controls in use cannot be adjusted with software. Upgrading these (to dumb mechanical valves set right) is the much of the cost.of the installation. eTRVs don't set flowrates before you ask. They're on off devices. The valve bodies are what balance the system.

You're looking at sCOP 2.8ish at 55C or sCOP 2.3ish at 65C all year. This falls below the sCOP at which the government considers there to be any carbon savings and more importantly perhaps below the sCOP at which you don't cause higher operating costs. Probably better to sell them A2A units at heating sCOP 5ish then let money saving expert show them how to use these to offset gas use.

Except most planning authorities block this for aesthetic reasons Sue them for damages. Cost of additional energy and CO2 offsets for the next 50 years. Haul them in front of their MP and the papers. Indefensible behaviour not in the overall public interest. Or just render your property including 200 mm of EPS in the render and invite them to go do one. Planning is not required for EWI any more so than it is for render. It is not legally an extension. Permitted development in the cast majority of cases. (my brother told Cambridge city council to go do one when they demanded a planning application for EWI; and you'll find that in their own solid walled properties that for EWIed there's no record of a planning application) The mistake that many make is asking permission of somebody who just loves any excuse to make you jump through hoops.

Ideally not. Ideally the controls would work AND the end users would do trying to dictate how physics works / knowing better than the device how to achieve the desired setpoints. Ideally they wouldn't rely on internet connectivity or have any connections to servers in hostile states though.

Careful there. That's sailing close to stating that the chap is always being a knob; not to mention nothing like the truth. In the UK I have non MCS, secondhand when installed, solar PV. A non MCS air to air heat pump that electrifies 80% of space heat for £1500 whilst also delivering cooling. Most of the results for minimal cost/effort. What I do think is dumb is expending lots of effort on a bespoke design that achieves a meh result. The difficulty you'll find with the "just whack a high temperature heat pump on" crowd mentality is (1) turndown at part load and (2) ensuring they're aggressively weather compensated outside of peak demand such that the sCOP isn't destroyed. All well and good in theory. Now go find some that actually deliver anything like what you think they do. Octopus hired the RED chap to cook up a high temperature propane unit that'll have good turndown that isn't £10k a pop. They're not there only ones working on the same. Previous advice was sit on the fence a while longer waiting for the kit to be available. Buy induction home and pans in the meantime; add pv if not already there which has a better payback on cost and carbon; chuck in an air to air unit that'll do your summer cooling AND reduces the amount needed from the radiators etc. All stuff you want anyway and is usefully absurdly in the form you'd like today.

Tidy lovely innit.

Exactly! Fake install price offer bait. Switch to offering to allow you to become the product.

Midea are a huge manufacturer. The units are made to a repeatable standard and they have a European presence. They're not like phinx et al shipping sketchy assemblies by the container. The monoblocs on offer won't set your pants on fire for flexibility in operation or efficiency in operation though. On the flip side they're cheaper than fish and chips. Good Energy are doing the same bait and switch lead generation based on false pretences game as British Gas / Centrica were here by the looks of it. Available in the middle of nowhere at half past never only.

The HSE believe that domestic gas safe folks* are competent? 🤣 *Even the ones in nationally branded colourful vans? In the real world you can fit your gas appliances if you deem yourself competent and don't make an unsafe installation. Enforcement is, by choice, nil other than failed domestic gas safe monkeys doing bad installs for cash and idiots stealing copper/bypassing gas meters. Even shoddy firms putting incompetent folks to work in multiple homes in nationally branded colourful vans don't get sanctioned. Ever.

IMO olumbing, electrics, kitchen fitting - anything that you can take your time on (without racing against materials drying); requires measuring with tools (rather than skilled eyeballs); and has to fit around other works (where you'd otherwise be calling somebody in multiple times to work unproductively doing part says)

Easy peasy. Long nose pliers and pull out the trap from above 🙂

Share a link / photo. The traps on these slot drains are usually removable from the top. This sort? https://www.youtube.com/watch?v=XL4XEZcmXWI It's usually a right pain to slide that grey part out and even more of a pain to slide it back in again. (tends to want to "pop out" again unless you get everything spotless) Ours has a strategically placed bottle cap wedged between the grey part and the wall of the drain to hold it into the pipe. If there's a second trap / alternative trap that's only accessible by cutting into the ceiling from underneath then that's a bit of an f-you move by the plumber. Cut in an access hatch as you'll be needing to de-wife / de-daughter that trap regularly. (short hair, pubes, soap etc sail though; it's long hair that twirls around itself then gets all kinds of non-rinsable conditioners and whatnot attached to it that really block these)

Good shout - thanks for the tip!

Which could also be filled with rocks, blebs of foam, and anything else that fit left in at the build / renovation / when the water board last dug up a pipe. I've seen a 50 mm pebble from there incoming mains wedge a 100 mm fill valve open on a tank for a big block of flats once. Created quite the swimming pool did that...

Domestic shower drains can have hopelessly poor traps in my experience. Work out how to pull the trap and unbung the hairsoap from it. No chemicals required. Pipework will be clear downstream of trap.

Energy price assumptions. EPC score is based on energy cost only. Newer EPC win have different cost assumptions. Get another if you care; updated with the more current yet out of date assumptions. 🙂

Wouldn't be so sure. Here's the list https://www.smartme.co.uk/smets-2.html Some models are chunky Vs what's there now - depends what the vendor wants to fit. E470s for example:

Your switchgear ought not to be in the meter box. Meter box: [Cutout > Meter > DP Isolator] External box: [your own switchgear] Do you need fuses or could you get away with isolators? (physically smaller) https://www.toolstation.com/axiom-isolator-with-enclosure/p92544 Ideally you'd have an N-way board sat adjacent the meter cupboard (one mains incomer / double pole isolator; with MCBs to feed man cave / ev charge / solar pv etc and indeed house if it needs reducing to 63A for reasons of long consumer unit tails?) That would also delete the Henley block up at the top; and give you somewhere to terminal the SWA that looks to go to another box in the top tight hand side. Depends on exactly which meter they wish to fit but I think you'd get away with there being enough space if you can delete the "man cave" switchfuse and the henley cocks above it.

I think the vendor will be in the business of selling these rather than ensuring that they live a long and happy life. Vac pump is as much for drying out the lines by boiling off any moisture under vacuum as it is for purging air. I'm sure it'll work fine though. I should add the ask no questions tell no lies minisplit kit to the tool loan page come to think of it. Vac pump, cutting too, flaring tool, cheapo gauges good only for checking vacuum/hooking up the vac pump. Annoying to post though as it'll barf out all the oil in the vacuum pump is tipped over and it'll take an age to drain it dry dry. Might have to be local only/hand relay only.

Great job! 🙂 Especially on taking control of the thing via tuya. fwiw I've found the vac pumps from "vevor" perfectly adequate for a handful of installs/reinstalls.

- Call out hydrogen-in-boilers as the most ridiculous thing you could possibly do at every opportunity - Campaign for welfare taxes/subsidies to be part of general taxation rather than on electricity; and for cost reflexive pricing on electricity including transparency on their make-up (standing charges are way too low vs reality; unit rates are way too high vs reality; all of which conspire to make heat pumps less economic than they actually are for UK plc) - Prepare for electrified heating as the house is renovated generally (induction hobs, electric ovens, sacking off gas fires, recreating space for hot water storage in many cases etc) - Decide when end of life is for your existing heating system so that the upgrades can be a thought through exercise rather than an almighty panic whereby the easiest thing to do is replace has with gas e.g. Newbuild gets heat pump. That's a no brainer. I don't have an air to water heat pump at the existing place in Cambridge though. Uneconomic at the time the boiler went in back in 2017 and still uneconomic/undesirable to install a hot water cylinder where none exists. I do have a little 3.5 kW air to air unit downstairs though; which has electrified ~80% of space heating load at a sCOP of ~5 if datasheet are to be trusted; for a peanuts installed cost and disruption. The combi is retained for instantaneous hot water and top up space heating. Radiators can heat the place with a 55C supply/47C return and the connections are all under the plinths; as is a 32A supply for a heat pump. Cooking is all electric already. When propane splits become available a tall kitchen unit gets swapped for the all in one tank. Hopefully they become available before gas standing charges skyrocket and/or disconnections cost real money. (next 2-3 years) Or when propane monoblocs ceae with their stupid restrictions on placement near doors etc. Prefer the split though to keep the size of the outdoor unit down, keep all water indoors, and keep the valuable half of the system indoors. (EV chargers are already starting to go missing; monoblocs won't be too far behind once the pikeys realise that two hoses and an a cable is all that secures a couple thousand £s outside the house and all you need to operate it is a new thermostat etc) Gas boiler is therefore end of lifed based on availability of alternatives / roughly in next 3 years rather than on it expiring in this example. There's been a few years of "whilst at it" preparation beforehand and a quick win of an air to air unit in the interim. (which given the low install cost, PV, and recent price hikes has probably already washed its face economically in addition to providing the welcome sanctuary when it's chuffing hot out) Alternative option is a standalone DHW cylinder with heat pump is and a slightly more powerful standalone air to air for heating. (probably a two head multi split) It's the winter DHW that's hard though.

Is planning permission similar to planning forgiveness? 😉

- Actual electricity and gas use - Reduce flow temps from boiler and if it works ok you know the maximum possible output from the rads at that - Crossed fingers with the "insulate or supplement air to air" get out of jail free card up your sleeve

I suspect it's common. Also in reverse. 24C and dehumidified slightly by having been actively chilled from 30C and 100% humidity to 24C by a coil at say 15C feels materially cooler than 24C and 100% humidity otherwise would. And in a related way folks with silver hair and cash to spare actually like it to be 23C or 25C in winter. That (1) increases heat loss AND (2) reduces radiator:room temperature difference and therefore output. So flow temperatures end up materially higher (~3C per degree of room temperature increase) and either the heat pumps can't do it (kW output drops as flow temperature increases) or they can but the COP plummets. You can bet the MCS tickbox brigade and indeed Octopus don't check that assumption either. They ought to. It's as material as stair lifts for some.

If retaining the suspended floors I would: - staple a "hammock" made of roofing membrane between the joists - pop a sheet of EPS in the bottom of the hammock as a "base" to spread it - but make this base ~150 mm BELOW the bottom of the joists - infill with mineral wool UNDERNEATH the joists - infill with mineral wool BETWEEN the joists - bubble glued chipboard over the top as the airtight layer/vapour retarder to prevent bulk movement to/from the house; taped to the walls and plastered over at the edges - floor cover over that This is similar to the ecological building systems photo above. Less resistant to wind-washing; but that's not a big issue on suspended floors. More than makes up for it by being able to double your thickness of mineral wool AND putting the whole of your joists on the warm side of the insulation. The hammocks end up looking a little like like this - there's a lump of wood in the insulation fill which is the joist. Will ask matey if he has any photos of a floor done this way. |XXXX___||XXXX___| |XXXXXX||XXXXXX|