Ed Davies

Looks like the forum software has “helpfully” inserted the wrong hover text on AAV here. I'm pretty sure Jeremy means Automatic Air Vent, not Air Admittance Valve. A Air Vents let air out, A Admittance Valves let it in.

Yes, here are some: https://www.rubitherm.eu/en/index.php/productcategory/organische-pcm-rt RT28HC is 250 kJ/kg so would need 14.4 kg to store 1 kWh (volume about 18.7 L when melted). Bit more than I had in mind. Prices varied from 4.4 to 5.7 €/kg when I enquired in 2005. Also flammable.

We need 1 kWh, or even a bit less, of PCM28, don't we?

@JSHarris what temperature range does your buffer operate over? Dropping the range to, say, a third of whatever that is would mean running the HP hourly which seems reasonable to me. @ProDave do I remember correctly that you don't have a buffer tank? Does your HP modulate down far enough to be able to run continuously?

What's your question about? The windows or the doors?

Holland is quite a small part of the Netherlands, basically the bit along the coast between Rotterdam and the Ijselmeer. This confusion is probably about as irritating to many Dutch people as referring to the UK as England is to many in NI and in other parts of GB. Having lived in Holland [¹] for a couple of years, nope, I don't remember encountering any hand basins with only a cold feed. That was a while ago, though. [¹] South Holland, to be precise.

My emphasis. Probably better said as “storing significant quantities” or something like that. Lower temperature water isn't a problem so long as the stored water is changed regularly and very thoroughly so the wee beasties don't have time to breed. This, to me, is a key attraction of the Sunamp. The quantity of water in the heat exchanger is very small and changed every time any meaningful amount of water is drawn off. Water-based thermal stores can have the same benefits but have the disadvantage of the temperature dropping off as heat is drawn out. A UVC, on the other hand, could easily have odd corners where the water doesn't change often which is fine if the whole tank is pasteurised regularly but a bit ickey if it could go months between high-temperature periods.

So, could you dispense with the mixing valve and rely on the heat pump's temperature setting to control the flow manifold's temperature? Advantages would be avoiding the cost and potential failure of the mixing valve and, more significantly, allowing the HP to run at a lower temperature as mixing valves need at least a bit of a temperature drop? Or would that require too narrow a temperature range on the buffer tank making that pointless or large?

So potentially 10mm out from one stud to the next. ? (1° ~= 1:60).

+1 I thought I understood but now I'm not so sure.

But @ProDave, that presumably works fine for you but won't set the right temperature for the OP's radiators. With mixed radiator and UFH systems I wonder if there's ever any sense in running the radiator return water through the UFH?

There are variants of that scheme with two units which synchronize: one pushes while the other pulls then v-v. Not sure how the communicate, whether you need extra wires or not.

I think they would. When I went to talk to SW to check we wouldn't go through one of their mains getting my entrance dug I also chatted with the engineer about my rainwater harvesting plans. Can't remember the exact conversation now but I did mention the possibility of buying in a few cubic metres in case of a drought and he didn't say it wasn't possible. BTW, BT and SSE were both very good about this check. SSE replied with a PDF map of their cables in the area the morning after I emailed them. BT took a little longer but sent a chap with a mine detector sort of thing to verify that, yes, their cables were buried on the other side of the road and they had none on my side. SW's office in Inverness were unhelpful to the point of obstructiveness and their web site's address for the local (Wick) office was about a decade out of date but when I found out where the local office actually was they couldn't have been more helpful. Engineer took me to his desk and called up the GIS plans of the area and we had a good talk about my project and the options for getting mains water to my house if I ever wanted it or to the other half of the plot for anybody building there did. So, @scottishjohn, I'd strongly recommend paying a visit to your local SW office and having a chat. If you're looking to rent out bits then rainwater harvesting gets a bit more tricky. The local Environmental Health people were reasonably happy about my rainwater harvesting plans but that was conditional on my not preparing food for the public, i.e., not running a B&B or anything. Also, they sent me a leaflet saying to allow 200 litres per person per day on the assumption of two people in each bedroom. I argued that was unreasonable as my house isn't intended for that level of occupancy and anyway you can easily use much less than 200 l/peep/day. I suspect, though, they'd insist on that for accommodation which is rented out.

Is this a first floor in the UK or US sense?

Sorry, yes, I should have said it'd not be “massively oversized”. It'd only be a little bit oversized.

But it does little or none of your DHW. If you wanted it to recharge a hot water tank at all quickly it'd not be oversized.

I think we need more context to work out what that really means. Can you scan/copy the relevant chunk of the “spec sheet”?

It's not 16.5 kWh per day, is it? That'd be a reasonable annual average for a not tiny house. E.g, decent but not Passivhaus so 30 kWh/m²/a for 200 m² comes to 16.438 kWh/day.

I tested mine along the length of my house and back. Also spot (well, line) on. https://edavies.me.uk/2018/09/laser-check/

Do you think a pair of these would be suitable: https://www.amazon.co.uk/Lorigun-Sunglasses-Transparent-Frameless-Rimless/dp/B07S6NFS5C/ref=sr_1_17

Hi, welcome to the forum. Be interesting to hear what you feel is “eco” about some of those products. Items 4, 5 and 6 particularly intrigue me. Is it a matter of lifetime vs embodied energy or something like that?

In amateur astronomy it's well understood that clouds are caused by people buying new telescopes.

Exactly. You'll likely only have a few hours of setting out work to do so arranging to do it when the light's pretty dim is not really a problem. Is that a horizontal and vertical line out of the front? The Stanley I have has that plus a vertical line out of the side at 90° to the vertical line out of the front. I didn't see much use for that at first but recently I've used it a lot to get the sides of the openings for my Veluxes in the sloping roof in the right vertical plane, by aligning the side beam with the joists running down the length of the house. Got easier with practice but harder with more window fitted as the inside of the house is brighter.

A bit, but it's tricky. In bright sunshine they're pretty much useless but on a cloudy day they sort of work. It helps a lot to have something reflective https://edavies.me.uk/2016/03/laser-level/

My brother in law owns/runs a landfill which has a lab to do testing of the water they release. I was hoping to be able to get them to test my rainwater harvesting system but my BiL retires at the end of this year so that's not going to happen. Still, another possible testing organization to consider for anybody who has appropriate contacts. Amusingly, they're testing the output of a large, as in shipping container size, RO filter which they bought second hand from Guinness because the output was too pure for Guinness's beer-making needs.