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Any form of direct electric heating produces 1kWh of heat for each 1KWh of electricity consumed. Anyone claiming their electric heater is more efficient than a different brand might bot be entirely accurate with that claim. IR heating is intended to heat the person rather than the room, and typically used in a cold building like a church to stop the congregation freezing. Do you really want a cold house? What is wrong with wet under floor heating and an Air Source Heat Pump that will typically give you 3KWh of heat for each 1KWh of electricity consumed? Mot a magic or false claim, the extra heat comes from the air outside that is is cooling and extracting heat from. You can easily DIY install a wet system on a suspended floor that adds about 25mm to the floor height. Just design for that so the finished floor height is where you want it.

A source of much head shaking over the years. I plan, I measure, I calculate, I re-check obsessively, then J walks in and shoves it a little to the left so it looks right. Sigh.

I’m just completing the plastering on a site The spec was to use these box covers At a cost of about 30 k for the whole site Zero patching around boxes and Electrian’s love them Will they catch on Is anyone’s guess

The absolute worst thing you could do with green hydrogen (if you had any spare) is pipecit into people's homes and burn it to keep them warm. Green H2 has it's place but that should only be for processes where it is absolutely irreplaceable chemically

First point, not cheap, noisy and maintenance issues is not typical. What were your problems? Second point, if the floor felt warm to walk on then the IR heating is not performing as IR heating (to warm the person) but is performing as resistance electric floor heating and warming the floor. Yes that will heat your house but at about 3 times the cost of a heat pump. And if an electric under floor system fails, (which they do) it is an expensive rip the floor up and re lay the heating system repair. Your choice and if you decide to go ahead please let us know how it performs.

Put lights where you need them, not everywhere. Illumination levels should vary based on what you're doing. We did Leds over the counters (food prep) then hanging lights over the table and island (atmospheric). Lounge/study is atmospheric, you don't need operating theatre grade lighting. Terrible pics as camera over compensates the lights, but shows you what we did. Downlights ABOVE the counters so your body isn't casting a shower on the food you are preparing. Leds stepped out so not above the tall units, so the light is between you and the cupboard/fridge/oven. Hanging lights over island which is our default light (atmospheric) . Table downlights for eating when you down need 500 lumens over your head. This works very well. Leds everywhere just tells me your electrician decided the lighting arrangement, and priced per fitting.

I’ll just leave this here re hydrogen. V interesting.

Those caps that fail are thin metal film, plastic insulation ones. The thin film is a safety feature, it means that internal insulation breakdown faults cause the film to erode away gracefully rather than abruptly, making the capacitance drop over time. I think that in PV type households this type of component used to give a constant current source giving non isolated low voltage suffers quite badly - I say that as we regularly get 252V acrms, and these caps start to degrade 😞. We had this with our old solic, also with the Honeywell heating controller (on cap#3).

Thanks P

A hydrogen generator is a fuel cell, so expensive metals and an ion exchange membrane. Then it needs pure, deionised water. Then water vapour needs removing from the gas. Then compressing. Then cooling. Then transfering into suitable containers at 700 psi. Then transporting. It is not like a school science lesson, that just heats the water up and releases tiny amounts of gases.

Not entirely true, there are some get-out clauses where the 99.6% requirement 'cannot be met'. The installer and the neighbour could reasonably argue that the requirement cannot be met because planning permission for a bigger and louder pump was refused, whereas the one chosen fits within PD rules.

Only for right angles.

Hi all My names Rich. im in the middle of a house renovation and extension. Im a chippy by trade so know my way around but its dealing with planners etc that spins my head 😂 Will be putting a post up about my trials a tribulations in a bit. All the best

Hello all. I am embarking on a new build and am experimenting with some new technologies for heating the building and water and keen to see what other people's experiences are of installing and using them. I also have a huge amount of experience, both good and bad, with all sorts of modern methods of construction and mechanical engineering products that I am happy to share. Thanks

I agree that basing architects' fees on actual build costs doesn't make sense, but that isn't what happens. As I understand it, the percentage is not applied to the actual build cost (which would be unknowable at the design stage), but to a nominal estimated build cost that assumes a particular level of finish. To rephrase your question from a different perspective, why would an architect's fee change just because their client decides at the last minute to put marble on every interior surface, add a solid gold bidet, and include 15 Miele ovens in their kitchen? The alternative would be to esimate the amount of time the job is expected to take and generate a cost estimate by multiplying that number by an hourly or day rate. I'm not an architect, but I'll bet that architects as a profession have figured out that nominal estimated build cost is a reasonable proxy for time, and easier to estimate. This is a different prospect from what I understood from your original post. Redesigning an existing plan on the same footprint, for which planning is already in place, should be way less than starting from scratch. To me, £5k sounds expensive for that.

Massively. Both on material and labour.

Quite probably not, depends on make and how it is set up. With a heat pump you have to re-learn how to use heating controls because, stupidly (and unlike many more enlightened countries), the UK didn't implement weather compensation on our boilers, which has increased the running cost of our boilers by about 10% for many, possibly most people (I can explain why). In general dont set the TRVs - see below instead. if you tell us what make your heat pump is we may be able to give more specific help but... Basically you have four options, of which 3 are reasonably efficient and the fourth is definitely not unless you have UFH and are already operating at a low flow temperature, say 30C or less. 1. Operate pure weather compensation: Leave TRVs (or at least most TRVs/TRVs in the main rooms) and any room stat set at least 2C above the desired temperature so they operate as temperature limiters, and the main control is the WC. Balance rads. Adjust WC curve as low as possible consistent with keeping your house warm. Leave alone Trvs will shut down the room where you have the fire. 2. Operate room-sensor-tweaked weather compensation: Leave TRVs (or at least most TRVs/TRVs imn the main rooms) and initially any room stat set at least 2C above the desired temperature so they operate as temperature limiters,. Balance rads. Adjust WC curve more or less as low as possible consistent with keeping your house warm, aiming to get it within a couple of degrees of the 'ideal' (which is scenario 1). Then use one pure on/off room stat or better still the heat pumps internal sensor (but NOT any room stat that attempts to be smart by applying a pulse width modulated signal to the heat pump) to control. This will result in long on cycles and short off cycles when its cold, and will be ~3-6% less efficient than (1) depending on how close the curve is to (10 3. If your heat pump supports it, operate in adaptive/AI/Smart mode (terminology differs - and this feature is NOT available on some heat pumps including Samsung, Midea and several others) Leave TRVs (or at least most TRVs/TRVs in the main rooms) and any room stat set at least 2C above the desired temperature so they operate as temperature limiters, and the main control is the Heat pump. Turn off adaptive mode. Roughly set up a WC curve according to the recipe in (1). Make sure that the bit of your heat pump controller with the temperature sensor (usually the one with the flashy UI) is in a suitable reference room). Turn on adaptive mode 4. Operate at fixed flow temperature using a room stat to turn the heat pump on/off like a (UK) boiler Unless you have UFH and are already operating at say 30C flow temperature, this is 20-30% less efficient than any of the above and may cause flow rate errors if you also have lots of TRVs. Not recommended. Hope that helps, Im sure if you tell us about your heat pump and which of the above you prefer people can give you some guidance. Once you get used to it you will most likely find that the levels of comfort are higher with WC activated. This is because there will be reduced temperature gradients across the room and less up and down of temperature with time. Low temperature heating (which is the essence here and its not specific to heat pumps) is actually more comfortable for most, its unfortunate that our heating industry has been up till now/still is rather backwards compared to many other countries.

morning, good questions. the reason I want to remove the plaster is because it's quite old and whilst it's still relatively ok (there are some hair cracks here and there), it doesn't look good. it's not at risk at falling down, but it's definitely not straight/level, it's almost as if it was done by a blind chap. second, it's extremely thick! now I know I won't be winning any significant space by replastering, but I won't lose another few mm by skimming on top. however, the main reason remains that it's decades old, at some point it will start blowing/cracking. besides, I don't like cheap jobs, so if I am to replace the ceiling/windows anyway, I might just as well do it properly, this is my home. modern finish, everything fresh/brand new, all done in one go, that's my thinking. the ceiling has got some of those typical plasterboard cracks (straight lines, worse in winter, barely visible in summer), so once again, that tells me the previous owner didn't do a proper job, after all the house was up for sale, so it was a quick job to make it look nice. as for the DIY element, I wasn't planning on doing the job myself, I don't do electrics / plastering / ceilings etc. I was simply looking to understand if it's realistic to expect a significant price reduction by me removing the plaster, flooring, skirting etc. Say for example this job is priced at £20k with me not touching anything, could I save £2-3k by doing all the prep work, saving the builder a few days of manual labour? if the consensus is likely not, there's no point me getting my hands dirty :). thanks

The formula you need is here: https://www.engineeringtoolbox.com/heat-recovery-efficiency-d_201.html

Exeter University took over Camborne School of Mines (just seems to be a cupboard of minerals now), but the guy running the course was important on the Channel Tunnel surveying team (think his name was Andy). Was 3mm in our case. Actually quite achievable and repeatable. After adding extra water with a dash of Fairy. For housebuilding, I would think that some decent matched tape measures, matching staffs, a large protractor, a long hose with clear ends filled with coloured water, a recap of SohCahToa, a laser level and some decent handwriting is all you really need. AND a fixed know point as a datum.

No idea! There is just A "Temperature Profile" setting , WARM , NORMAL, COOL We leave it on WARM most of the time, set it lower in very warm weather, but had no problem with over heating this summer. Increasing flow rate from 34 l/sec to 65l/sec increased energy use from 17W to 51 W.

Yes, I think you're right. But a reduced rate of 5% should be possible as a conversion from commercial to residential.

My Q350 now shows Extract Air 20 degC Exhaust Air 11 deg C Ouside Air 6.5 deg C Supply Air 18 deg C Running at 65l/sec (setting 2) at the WARM supply setting in a 215 sqm Bungalow There is a Temperature Profile setting COOL , NORMAL, WARM. Reducing flow to 34l/sec (setting 1 ) will probably increase Supply Temp by 0.5 Deg. Currently useing 17W at 34 l/sec May put an edit on when it has run for a bit at 1. I'm always surprised that ruducing flow rate does not have a bigger impact on supply temperature

You don’t need an architect get an architectural technician, you said it has planning, foundations poured, so you just need building regs drawings i paid £25 an hour to get my sketches turned into cad, retired architect I would expect £30-35 an hour now. I think you could get it all done for £2000-3000, it’s a very simple design.

We went through this process around 2020-2021 so allow for inflation. We had quotes from 5 different architects and architectural technicians. We didn’t intend for there to be so many, however, after the initial quote, when I tried to establish some of the finer details before we appointed them, like, ”exactly where is the airtight barrier?...” “”– the realisation that they didn’t really understand my point, made us think that it was going to be difficult to get above the “we just do building regs.” threshold, rather than getting as near to passive house as possible. The prices ranged from £3k to £30k. The house is around 400 square metres. Our build cost will probably work out to be around £1000-£1200 per square metre. I can’t personally get my head around the basic concept of charging a “percentage of build cost”. Why would the architects fee triple, if our build costs were say £3000 per square metre? Our groundsmen, bricklayer, plasterer, electrician and plumber all charge by the metre or day rate, so why should the architects fee be any different? It makes no sense! The prices didn’t include the structural engineer. One of the architects said they used a specific engineer who lived 80 miles away from us. Since he charged by the hour, any site visits (even a very short one) were effectively a day out due to the traveling at £700/day. The weren’t flexible enough to use a local guy, so we would end up paying for his driving time with not much to show for it. These sort of costs can add up over time. I think the biggest reason for the variety in price, is what stage the architect is at, in their career path and their business model. The highest price we got was from a “design practice” that were a bigger outfit, with maybe a dozen people working for them. They had a scale of charges for various disciplines e.g. draftsman £55/hr. to £85/hr. for a partner. I sort of got the vibe from the quote, that any variations that were necessary after the initial design would have been charged at the specified rate (ad infinitum!). A significant portion of the fee would have been swallowed up by the practice overheads and the drawings were still in 2D. In the end, we went with a young chap that I presume, hadn’t been qualified that long. He was fully fluent in Autocad Revit (3D) and totally got the passive house “thing”. He worked from home and his price was at the lower end of the spectrum and not a lot of difference compared to the architectural technicians. Minor changes along the way were provided as part of the package. However (and probably most importantly), he was great for bouncing ideas off, which is so important at the outset. I think you need to get ensure you get value for money!

The second time round We intended using our first build’s design as a template But the Architects said it really makes no difference to the cost So we started from scratch

I should add that the hard landscaping supplies I claimed for were all referenced in the landscaping plan that was part of my approved planning permission. Since you're required to include your approved plans when reclaiming VAT, I suppose HMRC could refuse to refund VAT on items not explicitly covered in the PP & which are also unrelated to the actual house structure.

Exactly and some of the figures I have seen as examples on a few websites belonging to architects are eye watering! Your figures seem about right. I’m expecting about £5k especially given that most of the work was done by the same architect with the previous owner. Everything is passed off by planning and permission is in place. I’m just looking to change the design on the same footprint, access, soak aways, landscaping, garage stays same too. I’ve even designed it for him! I’ll speak to him to see if we can agree a fixed price for submitting a change of design and getting through building warrant. If not I’ll look round for someone who can or brave it and go some of it alone.

Under G98 you're limited to 16amp per phase. You need to add up the potential export for each phase, its the potential that your DNO is interested in, not what you might actually do. If you add a battery(car or standalone) with its own AC connected inverter then you need to add the potential output from the battery inverter to the potential output from your PV. If the sum comes to more than 16 amp on any phase then you've gone over the G98 limit and need to get permission for the excess over 16amp via a G99 application. If your PV or battery inverter supports export limitation then you can get either or both set to keep your export to no more than 16amp but you still need permission via G99/G100

That's why Myenergi's post that they hope to bring such a charger out for sale next year is particularly interesting I think @Dillsue - https://www.myenergi.com/news/power-to-the-people-myenergi-starts-work-on-new-v2g-ev-charger/ Correct me if I am wrong but one of these + a £2000 old Nissan Leaf on your drive and you have a very high capacity/low budget home battery!?

I think there's plenty of cars including the Leaf that support V2G but there's no bidirectional chargers yet approved for UK use

I recommend you 'phone your local Western Power (now part of National Grid) office - you may be surprised by how helpful they may be! We had very similar situation, demolishing a 1950s bungalow with the original power cable from the bungalow wall hanging over the driveway to a pole near the edge of our land (thence across an A road to a transformer on another set of poles). We planned to install an external meter cabinet near the pole, initially to supply our temporary caravan, and when we're ready to supply the new house. The National Grid planner turned up for a survey, took one look at the old pole and announced they would replace the old pole and put in new cable from the transformer across the road to the new pole and down to our external cabinet... for FREE. All I had to do was build a wall and install the cabinets (one for their stuff, the other for us) and hockey stick. (And that was my first post!)

When working out the price of ToU tariffs, you cannot just add up the difference rates and divide by the number of rates. You need to use a weighted average as the consumption in each time slot becomes very important.

I have been using Cosy (with batteries) and it has been great. However now looking to move over to Tomato Lifestyle. They offer midnight to 6am at 5p and then 9:30 - 11:30 at 14p also 22:00 - 23:59 at 14p, rest of the time at 23p and none of the expensive period between 16:00 and 19:00. Bonus is that the standing charge is only 44p Even without batteries this would be far cheaper than any standard tariff and if you did your hot water run in the early hours at 5p and possibly increased the temperature during this period also it could work really well. With batteries its a no brainer 🙂

I signed up and came here to thank @eugen for his post on how to repair the Solic 200. My Solic 200 failed in exactly the same way as his and replacing capacitor C1 has fixed it and it is working properly again. It was straight forward to solder in the replacement. I am in the UK and I ordered the new capacitor from Farnell. The original capacitor was rated at 275 volts, I ordered a Panasonic rated at 310 volts X2 I received my Solic 200 in April 2022 and it failed in August 2023. I returned the 10 year warranty card to Earthwise but my attempts to conract them since August by phone and email have not had any response. Thanks again @eugen

please , ask your electrician to use non polarized capacitor 0.47 micro farad( this value is compulsory) minimum 300vac voltage! if use bigger capacity can burn the board , if is less you can have same problem as now! good luck

A 210 l tank full will take about 9 kWh to heat. That's 1.5 hrs with a 6kW HP. No amount of coil area is going to reduce it below that. So it is probably not the rate limiting step unless you have say a 10 - 12kW unit and are desperate to get the recovery time as low as possible. But a 12 kW one will generate HW continuously at over 5 litres/min which is rather better than an electric shower. So timing it for when you are actually using the HW might mean it does not deplete the stored water at all.

I measured the capacities of the 2 capacitors, of the 2 solic 200, the normal capacity( marked on the capacitor housing) is 470 nf (0,47 uf) , I got 198 nf for one and 220 nf for the second one (as I said, I have 2 solic 200)! I don't think it's about saving money, I paid for a quality capacitor (epcos) under 1 euro .Also 310vac is ok I think the quality of the capacitors used is poor or they have an old production date In any case, it is not very important, the important thing is that the problem can be solved cheaply. It is a capacitor that can be bought without problems from a local store, specialized in electronic components

I wonder if a house could be designed so that every angle can be a right angle somewhere. That is a brilliant idea, did the builders use them as place mats when having luncheon.

These are the gable walls, the black lines are where the crack run