joth

He certainly did install an a2a, you even commented on it 🙂

1. The ducts for effective cooling needs to be much larger than MVHR pipe that just provides fresh air , not energy transport. I found 200mm ductwork the sweet spot, along with 1m 3 slot linear grills. The space needed for central air is all in the duct work. Depending on the building shape it maybe trivial or maybe a major headache. You may need an oversize trunk and branch layout, best done with solid galvanised ductwork 2. I use Loxone which is hugely flexible but bit of a learning curve. The miniserver looks expensive but with no annual subscription but ongoing software updates I reckon it's pretty good value over its lifetime really 3. No. Use separate ducts. The only compromise I share the linear slot diffuser plenum in one room for both FCU and MVHR supply purposes. This was by chance (the only place i could put the fcu outlet was where the MVHR outlet already was) but works well. I have a hybrid: one room with dedicated FCU and two others share an FCU. An electric baffle controls air to one of the two rooms. (the other is the office and we just let that get air all the time. It has a much longer duct run so find it naturally gets less preference when the guest bedroom outlet is also open) In winter when no active cooling is needed I draw air for one bedroom from the other, circulating air between both rooms and the landing between. This really helps balance the temp across the building (else the empty room gets cold and our room to warm). Probably not a wise idea for covid safety though, LOL We nearly put an extra skylight in the loft space, wish I had as then we could easily purge the loft overnight which would supply all the cold air needed for all the night time cooling. Getting airtight extremal electric baffles installed is bit of a faff. I've been eyeing up main MVHR supply pipe,to share that existing penetration. if I put a branch in it and a duct mounted inline airtight baffle I could open this to steal cold air into the FCUs. (The balancing exit path would be out the skylight over our hallway, I think even when raining it'd be safe to crack it open half an inch)

Presumably also a condensate drain? Or you're limited to apex 13°C min temperature . Which to be fair is sufficient for our house

Somewhat interesting article in telling us what we already knew, but I bet most BH members will be rolling their eyes at the one topic completely conspicuous by its absence in the reporting.... https://www.bbc.com/news/business-66728800.amp "Funded by BP". 🤔

Personally I'd keep with a (3ph) smart meter, as it enables many more variable rate tariffs than an old school economy 7 meter, and having a large contactor yank out power from appliances outside the cheap rate is very brutal. If you want to control when your EV charges or ASHP runs it's better for the device and probably more user friendly to use the built in control panel on it to set a schedule or whatever. 3ph Smart meters are also required by design to do "net metering" across phases, which is important if you're having PV at all. Old school meters it's pot luck how the installer configures it (at least, that's what I was told by one supplier)

Are you asking about the DNO supply or what you route around the building? The for the supply, if there's no extra cost it's a no brainer, get 3 phase to the meter head. You can alway start with a single phase meter on it, and "upgrade" to 3ph in future if it's ever needed at minimal cost. Whereas upgrading the supply line to building at a later date will cost thousands. Aside EV charging (which I personally believe is a growing requirement here with us to stay, for at least our lifetimes), the 12kW allowance for solar before needing G99 paperwork is a big bonus.

Guess: often earth is not sent down swa (depending if it's a local earth stake or not, or separate earth bonding) and making one core yellow/green kinda limits what you can do with it. I for one feel dirty using yellow/green for anything other than earth. And I guess no blue because if you're driving a perfectly balanced 3ph load (motor) you don't need a neutral??? It's consistent with 3+E cable at least. I wired my driveway lights up yesterday, to a test 13A lead that was literally inherited from my grandad, so wiring red to brown, black to grey, and green to black gave me a right old chuckle.

FCUs only in upstairs room, UFH only downstairs. For cooling the FCUs run when the respective rooms call for cool. As mentioned up thread there's a buffer tank on the FCU circuit and when the buffer needs charging I also run cool water (slightly higher set point temp) through the UFH too just to increase the flow rate to avoid short cycling. In essence using the slab as an additional buffer. The manifold closes off any loops for any GF rooms that are already below target temp. So using thermostat control to avoid overshoot. In practice GF just sits at a pleasant temp regardless, it's only FF that really needs active cooling. I expect a lot of cool air tumbles down the vaulted hallway and into the GF open plan area. I don't have ducted return plenums upstairs, so each room's FCU circulation goes via the landing and shared spaces to eventually get into the service riser back up to the loft where the FCUs are, so helps mix up the air and give secondary cooling to the whole building. The FCUs have multiple windings so it's 3 or 5 channels of relays per fcu to control speed. (Nit: one FCU is a massive thing salvaged from a restaurant refit, which feeds two rooms with electronic baffles on the air side to direct which room(s) receive air. So the speed I run that one at is a function of the sum or demand from those room)

Yeah I used my rudimentary "overheating risk" approach with slab only in summer 2021 and was better than nothing, but thermostatic controls on FCUs per room is much better approach for us now. Very basic Visual Crossing template here: https://drive.google.com/file/d/1WL7LQopIfSp9aBHYtfYuHW-ti-nlTnnC/view?usp=drive_link Notes You need to put the API key in the place marked PUTKEYHERE in the URL. (see docs) You need to put your postcode in place of the POSTCODE placeholder I'm using JSON output as (bizarrely) that's much easier to scrape in Loxone than CSV. For some reason I never figured out, the date range URL params only work on CSV, JSON output seems to ignore them I'm only parsing current values right now, but adding forecast values is pretty straight forward if you copy the pattern from the params I've added The above is mostly used in another house with no weather station. On my house I primarily use Weatherflow Tempest weather station via the Weather4Lox gateway. This mostly works (occasional outage excepted) but the temperature sensor on it seems to have totally pooched and gives bonkers readings. (My other two sources are the MVHR and the ASHP, both via Home Assistant integrations, both of which recently broke too for various reasons, gotta love Home Assistant) IIRC The Weather4Lox plugin is tricky as it hijacks the Miniserver DNS query to redirect the weather request to its own implementation, so you need to setup the miniserver with that custom DNS server address and/or change your DHCP server to send every DNS query via it (no thank you). The Tempest has a neat(ish) feature that it automatically broadcasts all weather updates via UDP which is really easy to grab in loxone (no loxberry needed), but with the downside it won't populate the weather forecast tab in the loxone phone app (only their official weather service or the Weather4Lox spoof implementations support that)

Agree with B. Especially if the architrave is contrasting colour to the walls. But more over, line it up with the socket below (a single socket may actually be tidier there), and any downlight above if one is centered on that wall panel. You don't want it too close to the door as it suggests it's just for the WC behind the door.

Sorry not much to add other than, I use per room zone controls for cooling upstairs - each room has an FCU, fed from a 100L buffer tank. When I charge the buffer with 10° water I also circulate it through the UFH downstairs (so long as any downstairs zone, or the house as a whole, as cooling demand). This is mostly to increase the demand on the ASHP to reduce short cycling, but also has a marginal cooling effect downstairs. The only thing I do off the forecast is flag the risk of overheating (if today high will be over 27 or tomorrow over 28). And if this is true, various additional measures are taken Inc reducing the house target temp by 1° during cheap rate window. Not very scientific, but to be honest I'm reluctant to base too much on any forecast data as it has too many failure modes. Fwiw on another project I integrated visual crossing weather API directly into Loxone miniserver, very easy to use free API 👍 Can share some config it you'll find it useful

I'd sign up for a one month rolling contract, e.g. https://www.nowtv.com/broadband will do one month contract You'll have to pay like £60 installation, but that's a bargain compared to the £8000 I've been quoted to get FTTPOnDemand to my house (in the middle of a town) and I think it's worth paying for it now if you can so you can see the entire lot working end to end. Else like others say lay ducting now and hope. Use over sized ducting that way OR can always pull the approved stuff through it at a later date if they so insist. (IME they're very flexible in reusing any existing infrastructure but YMMV)

Sure, my thought is it'd be a shame to install thermostat now then have to rip it out and redo it in a few months if a change to variable rate billing is imminent

Any interest in ever using cheap overnight electricity like octopus Go? If so you want a nighttime boost rather than setback mode.

I haven't yet registered on thier site, but to check Is that available from https://www.freedomhp.co.uk/downloads/ ? (And as discussed here)

You can make any window into slimline appearance externally by overlapping external insulation and render over the frame. Improves thermal performance and can help with airtightness too

My 2x cost and 0.5x efficiency was based solely on this is what GB sol told me when I spoke to them, and was for the installed price of tiles vs infinity full roof of solar. This was 4 years ago so prices may have changed Also: - their infinity roof is quite poor kW/m2 so tiles may come out even worse when compared to modern high efficiency panels - they were very clear in saying infinity roof can only be installed by their own installation team (sister company), so if there's any challenges at all with DIY installing the tiles I'm sure they'd be very honest and direct it saying so

well, if it wasn't on the plans then it's not a big surprise the planning officer didn't comment on it You can either move it, apply for retrospective planning permission, or just ignore the problem until someone complains.

The 1m rule is only if you're installing it under permitted development. Building control don't enforce PD rules (in general) so not a surprise they ignored it, and if planning officers were looking at then it suggests you have installed it under planning permission instead of PD, thus if PP passed with it against the boundary you are good to go and should be able to ignore the 1m rule completely. If it's a boundary with a highway then this is completely reasonable. You're not going to keep anyone awake at night by blowing air into the street.

This is actually not a bad answer, in that you could copy what Loxone does. In its default config, after manual operation of lights it requires 1 hr of non occupancy before lights turn off. After that, it's back to the automation program. Vs When lights have come on automatically based on motion, it is only 15mins of unoccupied before they auto turn off. If you manually turn off lights, they remain forced off for 5mins before motion based automations resume. All these extension timeouts are configurable See parameters Met, Pto and Moet on https://www.loxone.com/enen/kb/lighting-controller/

In practice I don't think you need to do anything to cap the export but you need to confirm what evidence WP need that exceeding 4kW cannot happen. If they demand export limitation is put on both the old and new inverters it may cost more than the 3ph upgrade Fwiw is you didn't want the hassle of the 4kW cap then going with 3ph you could put the existing 3kW system on one phase and the new 3kW on a single phase inverter on a different single phase, and it'd all be within G98 and no impact to your existing FIT.

Last I looked at solar tiles (also GB sol) they cost 2x as much per m2 yet yield was 50% less per m2, so for a fixed roof size they give 1/4 of the kW/£ and half as much actual generation per year vs conventional panel. That alone is a none starter in my book. Having used gb sol infinity I very much doubt the tiles are ideal for DIY install either, but a quick phone call to them would answer that I think there's very few situations they aesthetic is really justified for the inefficiency. From what I know there wouldn't be many places your roof will be very visible from. The example photos above of GSE are misleadingly ugly as it's at a very close camera angle that in practice no one will ever be viewing a 3rd story roof from

Depends a bit on the application, but I'd steer for external grade cat6 minimum. And got CAT6A with U/FTP shielding if using for anything slightly unusual (high bandwidth, main WAN connection, HDbaseT, non ethernet usage like Loxone, etc). In practice having bought a drum of external CAT6A I just used that for everything. (I actually preferred it for internal use too as the slick gloss jacket was easier to pull through narrow openings)

At least one MCS installer I know just turns up and sees how many they can fit on the day, having made a conservative estimate of kWp at quotation time. Do any wholesalers allow 30 days for returns? Possibly overorder on panels and trays and return what doesn't fit. Else sell them here.

I suggested up to 4. I.e a reasonable upper limit, not a definitive goal. HDMI extenders can work over 2x CAT6, and that leaves one for internet and one redundant spare. However in the 15 months since I wrote that I tried various hdmi over cat6 solutions and disliked them all, so I'd probably aim for 2 or 3 max in key locations these days.