ProDave

I think you are getting confused. 12KW might be the maximum amount of electrical power you would want to use on one appliance on single phase, but a 12KW heat pump will probably only use 4KW of power. So on that basis if the heat pump were to use 12KW of electric power it would be a monster with an output of over 40KW Re heating power requirements, our house is not as good as some on here, but not bad, needing about 2.5KW of heat to maintain 20 degrees inside when it's -10 outside. And that will be provided by a 5KW ASHP.

Don't tell me you bought the one Jeremy was selling?

I was just commenting that people in general have a fear of noise from a heat pump, but you never hear anyone saying "I don't want an oil boiler in my house because they are so noisy"

It is funny that some people get bothered by a gently low level noise from a heat pump outside, yet the same people are happy to have a pressure jet oil burner roaring away inside the house creating very much more noise.

Get your site insurance BEFORE you start. Some get shirty if you have already started. Surely you should not start until your building control have all the drawings and have signed them off?

That all depends who plumbs it and what valves they use. I prefer separate 2 port valves and this programmer will do fine, there are other 3 channel programmers around but not many.

I will be using a Horsman Channel plus H37XL. One of only a few 3 channel programmers so I can have separate times for upstairs heating, downstairs heating, and hot water.

Easy question snd yes I would. I had something like 5 quality window suppliers quote, Rationel were the cheapest and the second best in terms of U value. Only Internorm offered slightly better UW values but at twice the cost. But do shop around, prices vary and someone even once reported Intenorm being cheaper than Rationel.

I have and @Stones and I am sure a few others.

17M is a long way. The issue is the time it takes the hot water to get to the tap. I would first look at getting the HW tank more central, if not a recurculating hot water system.

They should have a maunfacturing date somewhere. That site does not say WHEN the Firex brand was discontinued, just that Kidde took over he brand in 2009 and it is now discontinued, so it might have only been last year that they were discontinued and they might still have been current?

Your electrician is going down in my estimation. Old stock, discontinued in 2009 https://www.kidde.com/home-safety/en/us/about/firex/

Buy a decent make like AICO. They are not that expensive if you search on line, and there is no issue replacing a failed or time expired unit. Apart from anything else, AICO are one of only a few with decent back plates and decent electrical terminations.

A number of issues. The rules are different in Scotland and require hard wired mains powered smoke alarms. That requirement may come to England in the future. The electrical regs are all about voltage not power. A 240V smoke alarm comes under the same regs as a 10KW heater. England and Wales has Part P which imposes restrictions on who may do certain wiring e.g new circuits, or circuits in bathrooms. Scotland and NI does not have this.

What is it about ASHP's that has put you off? The other side of the coin is GSHP's require rather a lot of antifreeze, which is supposed to be replaced after a few years with a disposal cost. That was what put me off them. I have no doubt they work but the extra eficciency compared to an ASHP appeared to me to be lost in additional costs. Another factor which is not often discussed, the "workings" of an ASHP usually go outside. but the workings of a GSHP usually go inside which is more likely to be a noise nuisance in the house.

@recoveringacademic Are you thinking of it just for tiles / slates, or are you thinking of it for the solar pv tiles (that they make some spurious half price claim for)? A company I worked for did some work on individual roof tile solar pv panels. In this contect we made a laser micromachining system that did one part of the manufacturing process. But the thing that struck me was you would have hundreds, possibly over 1000 individual solar panels to connect together, and I could imagine the connector system being a bit of a nightmare.

@billt Your system is unusual, but not disimilar to many I see in remote places up here. But I still by far maintain the best arrangement I have seen for such a system where the supply was from a stream at the bottom of the hill, pumped up with a hydraulic ram. So the water arrives in bursts, a small amount each time. For this they have a SEALED underground tank which is where the water goes. From the underground tank, there is a submersible pump, actually a borehole pump as it was all he could find. This pumps water from the underground tank to a large, probably 300L or so accumulator (pressure vessel rated for potable water) It then flows from there to the house. The sumbirsible pump is operated from both a pressure switch in the expansion vessel and a float switch, so as long as there is water in the underground tank, it will charge up the accumulator. This works very well indeed. You would think you are on a decent pressure and flow mains supply with always plenty of water on tap. You do need some safety systems which were missing when I first met the system. The relay driving the pump had welded, so the pump just kept on pumping. The water in the tank was up to 12 bar, there was no over pressure relief, and pipe fittings in the house were starting to let by. It now has a double relay system switching the pump and an over pressure relief on the pressure vessel.

A small combi is probably the root of the first problem. Fit a decent size or better, a system boiler and a good size unvented hot water cylinder. The second problem may be poor mains water pressure or flow rate. you mention a private water supply.. Borehole? Spring? moire details. If flow rate is poor fit an accumulator (big expansion tank rated for potable water) at the inlet to boost flow during high demand. You "solution" of a big water tank in the lof just ensures that all the taps get low pressure and flow, rather than that only being a problem if you turn on too many at once.

Just what do you want your attic water tank to do. If it is to provide the header for your how water, that's not just last century, the one before I think. Have you never been in a modern house and marvelled at the hot water coming out of the tap with the same force as the cold water? In warmer climates they put the hot water tanks outside, but that would not work very well here in the winter.

We made that mistake (were advised badly) at our last house, so we make sure we only ever get it desludged in a very dry spell when we know the water table is down, e.g. it was done just a couple of weeks ago after our long dry spring / early summer.

Every day is a learning day on BuildHub. That has certainly made it near silent, but I expect the flow is MUCH lower now. I will have to check on the flow meter if it is enough.

Interesting. I just copy a link and paste it in with Cntr V, no special tags or functions and it always works. Here is a boring example http://www.ukho.gov.uk/easytide/EasyTide/ShowPrediction.aspx?PortID=0256&PredictionLength=7

The standard, tried and trusted UPS2

A word of warning. Don't plant it in shingle unless you are VERY sure the water table will never come up high where you are.

It has 3 selectable speeds, no mention of curves. Oddly the fastest speed is quietest, at the slower speeds it has a very pronounced irrirating hum.