JohnMo

How has your system performed over the hot periods?

And building regs edition, applicable to your build

To be frank I've done the course and G3 doesn't mention it directly - But with mixer taps you need a balance pressure between hot and cold otherwise the higher pressure wins and you don't get any mixing. G3 limits the pressure to the cylinder to 3 bar(g) via a mandatory PRV. This usually comes in the form of a combination valve which includes a cold take off port for cold water which is also regulated down to 3 bar(g). However if the incoming main has a PRV installed and set to 3 bar(g) or below, the whole house including cold water and hot water cylinder will be at around the same pressure. However if you go this route there is there is a chance of reverse flow so you should install a check valve on the hot water outlet of the cylinder. If you don't have balanced mixer taps, mixer showers, and mixer bath fillers, then no balance feed needed. BUT you do have to include scold prevention measures as no auto regulation of supply temp occurs. The water in an unvented cylinder is classified as wholesome.

Think your missing something. One of the rules is the east and west face panels have to be matched. They are comparing essentially 4 systems. One thin film, to one inverter and also 2 inverters, same for Crystalline.

Maybe overthinking it, lay it, add a bead of sealant, you will never look at it again, neither will anyone else.

Our garage is all Douglas Fir and Scottish larch, none of it is treated, as it all came straight from the mill. All the structural wood being Douglas Fir.

If you want it on trickle why not out a proper dMEV fan in that is actually almost silent or MEV? Greenwood CV2 or CV3?

No, but others have. Here you go something to read se-ta-efficient-east-west-orientated-pv-systems-wi.pdf

I didn't until someone here pointed me towards design / install instructions that said you could, so researched further. And indead you can and the output per year is actually better than 2x MPPTs as they run longer at best efficiency point. But strings need to be identical, as in number of panels, mounting angle.

Someone is declaring the property is completed to building regs and all planning drawings. It's a legal document. Any muppet could sign it, so they have asked for the PD to sign, so competent person.

Hybrid inverter. But they are generally equipped to do limited off grid output. Some makes will do a gateway which will allow the full inverter output in a power cut. Or AC coupled battery with gateway will will allow normal string inverters to work in a power cut. Depends if you already have your battery? All the above depends on what you mean by off grid?

You just put the new one a different inverter or if your existing inverter has spare MPPT do that, then they can be anything you want. East and west can go on one MPPT (but need to be same panel design, same number of panels and same angle) or 2x MPPT if you want. Do not connect on the same MPPT as your existing South facing, as new panels are very unlikely to match your old ones

https://www.concrete.org.uk/fingertips/non-ferrous-metals-in-concrete/

How do they get any work at those prices? I knew they were expensive but that's mad

I just signed the completion certificate myself

Ours ended up the second highest band -3 bed bungalow. Trouble is our views add to the selling price of the house and house is geared to fully take advantage of the views. Good job we have our own water and sewage as would have just over £1k to the council tax bill

Just stumbled across this worth a watch https://youtu.be/j4qF86jRj7A?is=RevzL-409AChEw5j

Interesting the difference location makes. Just looked at previous posts and you have Large solar array 3kw facing SE and 6kw facing SW with no overshading from trees / chimneys etc We have similar amounts of PV, but in NE Scotland instead of Hampshire, plus we have morning and evening shading. Interesting is Jan to March we produce similar to you, we have an array of vertical panels which helps, and the over shading is less of an issue as the sun sets before it gets there. But after that we fall well behind by about 40%, this is a result of the over shading and the vertical panels optimised for winter production.

Depends on the investment to get £60. Even a small battery could take advantage of Axle VPP and get £1/kWh we have had 4 events in the last month. using a 2kWh of battery capacity on Axle events would be 2kWh x 4 x £1 = £8 per month or £96 (plus if getting export payments that could be 12p x 8 x 12 or £11.50 on top) a year. Plus the rest of the time it could take you through an expensive period on a ToU tariff and get you cheaper electric for heating water/CH etc for 8 hours a day. so if you are only saving £60 something is very wrong. Good guess the battery isn't for you.

Just looked back at our gas and electricity bills in 2023, we had £89 Direct Debit for gas and £180 for electric. Since then I have added more solar and a battery. Plus we now get export payments. Plus got rid of boiler and installed an ASHP. Battery and additional solar cost me around £7500. Fully installed. But current DD is a total of £52. Instead of paying normal rates for electricity I pay 10p per kWh, can only do this because I have a battery. So in simple terms I am saving £214 monthly, or £2568 per year. Nice round 3 years pay back on the additional solar and battery. And an added bonus, this month via Axle VPP, have earned an additional £20 directly from having a battery. So taking this into account in the the above, now pay back becomes 2.7 years.

Basics over size MVHR unit. So fan speed is low for your flow rate. Minimise pressure drops through duct work, via large ducts and or multiple duct runs. So low velocity through ducts equal to low noise and again less fan work being done. But if you're not better than 3m³/m² @ 50 Pa airtightness don't bother with MVHR. Better options available

Our first quote was £10k - it was dismissed very quickly

Once you get your head around it it's a pretty simple system. Pretty easy to install if you plan ahead and know your duct routes. Our whole system was around £2k installed and commissioned DIY basis except commissioning sign off. To certify yourself you need a certified Then you can self certify. I paid £200 for someone else to do it.

No I just did a degree on the subject in 2000-3, so a little ahead of the curve. I have my own view, thanks

I would do a timber structure attached to wall and then skin with plasterboard