Bramco

I see Solis inverters with multiple MPPT trackers on the ITS site -> https://www.itstechnologies.shop/search?q=solis but maybe they aren't series 6? Simon

@MoDo That seems lower than the uplifts I seemed to be getting on quotes, although it's hard to work out from a quote. Maybe a way forward. Wonder if there's someone that would do the MCS for a battery install - a lot simpler as there's no heat loss calcs. Can you share the name of the folks that would do it for an ASHP? Simon

@MoDo Cool Energy's installers did the install, the MCS paperwork and the grant application - the couple of hundred quid was what the bill came to less the £5k grant. Obviously now that's £7.5k. Cool Energy have now taken over their installers business and are running things themselves - think a couple of the guys moved to Octopus to start their ASHP installation business. I think but I'm not sure that you can apply for the grant yourself but then you'd need to get the MCS paperwork done - that's if that is important to you, lot's of folks just install their heatpumps themselves without the MCS paperwork and associated uplift. Simon

Per-empting a new Boffin's topic Terry, a lot of non sysadmin folks have to rely on off the shelf solutions and often won't realise what the impact of an internet outage or a router failure would be until it happens. There's a lot to be said for making sure that you aren't relying on cloud based services for critical functions like the CH and DHW. Having said that, most suppliers aren't stupid and have built their systems so that they will continue to function if there is an issue with the internet/cloud. So apps are there to report on what's happening with the system and to alter settings etc. not to do the real time control. Our CH system which is managed by the ASHP controller and by thermostats would continue to run even if the internet was down. Similarly, the Battery/PV inverter and the PV diverter would also continue to run. OK, I wouldn't be able to use their apps to see the system status or to change any settings but I could get off my backside and go to each of the controllers to make the changes on the device in question. Where we might have a problem is that we use Google Assistant to switch on some lights at dusk and with a spoken command to turn them off at night. I don't think this would work without the internet connection, so we use Sonoff wifi and zigbee switches in the back boxes behind the switches, so we can always walk round and turn things on and off even if Google Assistant can't do the switching. So I guess generic advice would be to check everything that is automated with standard parts to make sure it will work even if the internet isn't available and for anything that won't, make sure that you have a backup in place, like properly wired light switches. Simon PS Look forward to further discussion in Boffins corner when you make a start.

We don't hear any rattling - but we're triple glazed and the blinds are all under overhangs, although that shouldn't really make any difference I guess. Simon

You must be looking at different Hallmark blinds to the ones we installed - think I put a link to the company that did ours above. Ours is a high spec airtight house - with motorised blinds, the only penetration is the cable from the wall panel through to the top of the blind. The motor sits above the blind (in the cassette if you have these installed). So it's easy to ensure that airtightness is maintained and there's no cold bridge. We had simple up/down wall switches fitted that are also wired to a central master where the anemometer comes into. There are more complex controllers which are wireless. See the Somfy controller range - Somfy were the standard controllers for our Hallmark blinds - think they're probably the market leader judging by a bit of googling. As @Thorfun said, if there's a power cut head for the pub... but seriously, unless you're in a really rural location, will a power cut last long? Or from another angle, isn't this a great opportunity to convince the boss that a battery system is essential, so the blinds can be controlled in the event of a power cut. Simon

We've been in debt to Octopus for about a grand since last winter and they've never asked us to increase our £50 monthly charge. We've paid it off now but I wonder how long they would have let us keep building up the debt. Simon

On the Sunsynk, critical loads are a separate connection - there are 3 ac connections on the Sunsynk Ecco inverters: grid which is bidirectional, critical loads and one for a generator/wind turbine. We've just fitted one of the 5kW inverters with 3 of the 5.1kWh batteries and are very happy with it - so far..... The instructions for setting up how the power flows are a bit crap though, took a few tries before we go all the right boxes ticked. We have a 6.5kWp solar ground mounted array (with planning permission, we're green belt, so had to apply). Our sparky also advised a DC cable for the array to the garage which is about 60m distance. So as per @JohnMo's post above 4 core armoured cable. Simon

@JamesPa Flow out is about 30C and back is around 25C. The ASHP is set to 35C but even when it's not defrosting, it never reaches this, so it runs continuously for the full 4 hours. When it has to defrost, you can see a dip in both the ASHP output and input and the UFH feed and return. I think we'd set the ASHP setpoint to 35C to aim to get a flow temp approaching that but with the way things work, i.e. the ASHP never really reaching the setpoint, it's actually probably working optimally, in that when the ASHP doesn't have to defrost it runs continuously, so is probably getting a great COP. Sadly can't see this on the Cool Energy units - I'm considering putting one of the open energy monitor ASHP kits in so that we can see what we're really achieving but that means draining down the ASHP loop to put a heat meter in, so will have to be done in the summer. Graphs below to give you an idea of how things work - our build was almost passive house, very airtight, MVHR, insulated slab with embedded UFH loops, so we don't need much heat and when the slab is warm we don't lose heat v fast. Warm night, so a bit above normal, no defrost. Cold night with defrost. Given it was very cold, the immersion in the UFH tank we use for a boost when it's below 5C was probably also on.

@JamesPa This is exactly what we did. We'd had enough of the daft quotes for ASHPs, especially those that insisted that they would have to do a full heat analysis, when we already had that from our M+E consultants.... And then of course there was the MCS markup... So we went ahead with the cylinders we'd specced in the M+E report. 300L DHW with 2 immersions and an UFH buffer tank also with 2 immersions. Both with about 3m2 coils. The DHW tank is also heated from a solar PV diverter. The plan was to use Octopus Gos 4 hour 9p window for both the DHW (if not enough solar the previous day) and for the UFH. When we realised that the BUS grant was also available to new builds, we looked around again at ASHPs - in the end we had a Cool Energy 9kW installed which cost us a couple of hundred quid. They were happy with the heat analysis from the M+E report and the tanks that were already in place and did the grant submission as well as the MCS certification. So for us a no brainer. We now run the ASHP on heating for 4 hours at night instead of the immersions which except for really cold days is more than enough heat. The DHW is still on the immersions. We worked out that having the ASHP on heating only for 4 hours was the most economic way of doing things. If we ran it for hot water outside the 4 cheap hours it would be more expensive than a scheduled run of the diverter for the 4 cheap hours.. @Bruce you should contact Cool Energy in Grimsby about a price for one of their 9kW ASHPs Simon

That looks like it will. But most hybrid inverters seem to have this capability - some more flexible than others. Our system with the 5kW inverter handles all our daytime needs, we charge from solar and Octopus Go cheap rate at night if needed. Simon

@Caddy - that looks expensive. You need to add an inverter as well. Also, watch out for the larger batteries - that Lemon one must weigh about 150kg if it's 15kWhs. We recently installed a Sunsynk 15kWh system bought from ITS for just under £5k, including the inverter and with VAT and delivery. This was a self install, so we had to pay the VAT. Don't forget if you want to take advantage of the zero rating for VAT, it means that you will probably have to have an MCS installer do the work and that bumps up the whole bill by quite a lot - generally a big chunk more than than the VAT you would pay on a self install. Simon

@Alan Ambrose We were advised to install an anemometer - which we did - as well as the master controller that would raise the blinds when the wind was too much. As I said earlier, it triggered once but we decided that given the blinds are effectively our curtains in the master bedroom that we'd risk of turning off the automatic wind protection. That was over a year ago and we've had some pretty ferocious storms since then and we haven't had an issue. That's with blinds that are down and closed as well as down but horizontal. It may be different with the interlocking versions which would create a large closed surface but with the ordinary ones, there's plenty of gap between each slat for the wind to blow through. And thanks - we're very pleased... 😄

Same here. @Alan Ambrose if you want to see what the overhangs and the blinds look like, take a look at our architects web page -> https://lhc.net/projects/ashcroft-creating-a-low-energy-family-home/. Be careful with comments, the architect is our son 😉 🙂 . It's also worth noting that with the width and spacing of the blinds, from about the spring equinox through to the autumn equinox the blinds when horizontal block out all the sunlight. It's only from the autumn equinox to the spring equinox when the sun is lower, that the sunshine gets through - so a great solution.

Tiltable venetians. They were supplied through hallmark blinds - but essentially they are made somewhere like Poland to order. Here's the link -> https://www.hallmarkblinds.co.uk/external-blinds. Scroll down to Trojan exterior blinds. We looked at quite a lot of other suppliers, who either weren't interested or were stupidly expensive. We also hate curtains but these work effectively for our master bedroom at night. I think there is an interlocking version but we just went for the standard version and they are fine. There are various Somfy controls, either hard wired or wireless and there's an automatic system to raise the blinds if it's too windy outside - we've disabled that - it's not a great look looking for the switch to bring the blinds back down again when yr stark naked - fortunately we're in the countryside though. Simon

We have the MBC 0.14U walls as above and blown cellulose vaulted roofs - think we got up to between 25 and 30 degs during the hot weather but it wasn't enough for us to wish we'd put a cooling system in. One thing we do have are lots of sliding patio doors. The ones on the south elevation all have overhangs and external blinds. So in the summer the sun never really reaches the doors and in the spring and autumn when the sun is lower in the sky, we can tilt the blinds to reduce the solar gain. In the winter it's great, the sun streams through the doors giving great solar gain. Bit more expensive than silver foil but a little more versatile.... Simon

Yup. Make sure that the mesh wifi points also have at least 2 ports - one to connect back to your Virgin router and another that you can stick a switch in, so you then have local ethernet connections where the mesh wifi point is. We have one wifi point in the garage connected to the router (EE 4G) with a 4 port switch. This then connects to the plant room by cable. There's an 8 port switch in the plant room and a mesh wifi point outside. The switch connects (cable) to another mesh wifi point in the lounge/dining/kitchen and then there's a mesh wifi point on the landing (no cable). Everything works very smoothly, obvs we've turned off the ee router wifi, so only using the mesh wifi. Tried all the wifi extenders etc in a previous house and they are very flaky - you'll regret going there... Simon

I don't think EDF will care whether the inverter is replaced or not - as you say, they are only interested in what you generate. Personally I wouldn't inform them. I don't think the DNO would be interested either, especially if you are under the 3.whatever limit. If your array is larger than the limit, then they would ask for a G100 compliance certificate. So look out for a replacement inverter that includes an export limit manager and has a G100 certificate. Lots of them do. When we submitted ours for approval, the DNO asked for an electrical certificate but weren't interested in any MCS twaddle, we just said it was a self install. I don't think this is a legal requirement, just them making sure that it has been installed according to the regs. So if you have a tame sparky who would do the certificate if you were to do the replacement, then maybe this is the way forward? If not, it's a pretty quick job, so shouldn't take a competent sparky long. Simon

This could also be the input rating as well, so it would take a long time to charge up the 15kW capacity. Also the 4000 cycles might mean that the Fogstar batteries are recycled cells, which might account for the pricing. Most of the other battery suppliers are at least 6000 cycles, afaik, Tesla is unlimited. Key things on battery specs are obvs the size but also, cycles, DoD and the output. Hopefully the transport co will be delivering our Sunsynk batteries today - then the fun starts with the installation - although it all looks pretty straightforward. We'll be charging on the Octopus Go 9p rate for 4 hours at night unless of course the sun has been shining in which case the batteries should be almost full. Simon

Certainly not taken as criticism. Everyone to their own as they say. We have some pet hates - one of them is hand rails and spindles - which freed us up to do the lighting - or rather allowed our architect (our son) to come up with the great solution in the photo.

Agree - but you've missed out candles.... 😄 That always seems to be a lot of expense when you can just walk across and use the inline switch on the floor or table lamp - or just have it always on and use a wifi switch. Agree - we also have some under the banister on the stairs - very effective..

That's the look we were looking for 😄 We also didn't want spots or chandeliers - too busy. We're happy with the flat look, I'm sure you're happy with the spots. I'll have to try to take some photos when it's dark to show that there are plasterers around that know their business. Simon

Fortunately ours were brilliant. Looks great during the day and also at night when lit. Maybe we were fortunate. Simon

You can't get away with tongue in cheek here can you....... But while you say it's impossible - it's also important to do the homework - how many appliances might be on - can the inverter and batteries handle that and how long can they handle the demand. As @ProDave says - most modern appliances will simply give up the ghost and go into standby - so not a problem - unless your washing is sitting in a vat of warmish water. Simon

Surely the switchover will be handled by your inverter and it will be imperceptible as far as the appliances are concerned. Also on having too many power hungry devices running when the switchover happens will again not be an issue, because you'll have done the analysis to make sure that the battery and inverter can supply more than enough to supply all the appliances you might have running - surely.