JohnMo

A 2 port buffer doesn't require to be heated first, as the main flow goes direct to the heating, anything not required for heating will the heat the buffer. Once buffer is up to heat the heating will be drawn from buffer as the ASHP return temp will be satisfied.

dMEV goes in a hole made in a wall same as a normal vent fan, but has built in supply and extract with heat recovery. No need to access to any inter floor spaces as there are no ducts.

I would really investigate the insulation and airtightness, get them all to a very high standard. That size of flat will only need next to no heat then. The heating requirements should so low that the house will take the excess heat from the flats connected to it. You should be getting your heating requirements down to below a 1kW for the whole flat. Install dMVHR for ventilation. Electric UFH heating in bathroom,with electric towel rad, on a timer. Simple panel heater or storage heater in the living space, immersion heater on suitable tariff for hot water, or air source Hot water tank. But take air outside, not inside.

Great, thanks

Not sure if this is the correct section? I have a central heating pump started by a flow switch. But want to start a second pump about 10m away with no wires between and a very difficult route. Looking for a wireless way to connect the second pump (pump has main power next to it). Or more precisely tell it to start when the first pump starts, without a wire between the pumps. Though about a pair of Shelly relays, but not sure how to go about it or if there is anything else I can use. Don't want to rely on having internet, unless I have to.

Generally taken on here as snake oil. You need an unvented air gap either side to get quoted performance, by this point you are taking up as much space as mineral wool, which cheaper.

You will need an accumulator, it doesn't need to be big, think ours is 50 or 70 L. This will ensure water comes out of the tap, when you open the tap. Otherwise you would have to wait for the pump to start before water came out the tap. Plus the pump would be stop starting every time you open the tap for a couple of seconds, so wouldn't last very long.

On a borehole pump the accumulator is there to do two things. 1. it gives a pressure that ensures water flows out the tap when you open it. 2. It limits how long you pump runs, a pressure switch will shut off the pump, when it's pressure is met. The pump will not start again until a suitable fall in pressure occurs. Storage tank. To give you a 2 bar supply pressure the storage tank would need to be 20m above the highest outlet in the house. So a pumped solution is the way to go. The borehole pump can be quite small low head pump and it pumps between high and low level switch in the storage tank. It does need to do this quickly. The tank can be above or below ground. The storage tank will need a transfer pump that charges an accumulator, then is filtered/ treated prior to going to the taps.

If you do intend to go thermal store, with an ASHP, you need to ensure you have either specify very large coils, which may not be practical, but better to have either internal or external plate exchangers for heating the store and for DHW take off, size to suit the flow temperature from an ASHP. You need exchangers that give max of 2 degree approach temp (difference between heat source supply temperature and the secondary side outlet temperature). If you are heating the thermal store at ASHP temperature it will need to be larger, but heat loss should be similar to an UVC as it will be at a similar temperature. Boiler stove adds complication, and is only worth the expense if you intend to use a lot. On only when really cold may be a waste of money and effort. Just install a non boiler. To save £100/year, from the boiler stove you would need to heat a 400L cylinder from 35 to 70 around 100 times a year. Assuming your wood comes free. Keep it simple, cheaper to install, easier to manage. Spend the money saved on insulation. Aim to get the heat demand at or below 15W/m2, then your UFH flow temps can be sub 30 degs all the time.

I forgot that one, we had loads of wild life surveys to do and wait for some squirrels to finish nesting first.

Basically what I was told that we could do anything that does not require planning. So we did access to site, some tree removal, laid hardcore, flattened the site where required, ready to do foundations without actually start the foundations and get the equipment to site.

Doesn't really do justice again.

What ever you make sure you can maintain it later when lights fail. No point doing something that requires a scaffold to fix. Also the further the light from where you want it the dimmer the light will feel. We went for up and down lighters high on the wall. Overall it works great, easy to maintain, light where you need it.

Third thread today on sand batteries

At 500 degC you can make high quality steam and drive a steam turbine generator - electricity.

Do you have an immersion diverter or timer, this will use some of the surplus PV power to make DHW.

Looks fine straddling the insulation band concrete.

We never asked for permission, as we got the caravan with the site, so assumed it was ok. And it's a temporary building as such. The council assessed it for council tax and we now pay council tax on that, once we get house sign off that will revert to main house. We are private water a sewage treatment, so that was deleted from the council tax bill.

May be worth adding a drawing of what the floor to window interface will look like. You should be able to plot the heat transfer path at the base of the window from the drawing.

Used GRC Aquatech at Insch Aberdeenshire. Filter system was installed about 10 months ago, pump a couple months before that.

I think your extension will be difficult within the budget., You seem to two lounge and dining areas, which seems loads of dead space. As said utility is huge. Also the kitchen, diner sitting area looks very spacious.

If your doing a split ASHP you need F gas, otherwise no. Why waste 5 days of your life and £1k.

My borehole is 34m deep and 27m of steel casing as it is mostly sand. The borehole finished was £5k. Test pump hire, £350 Final pump and control, £1700 Filter system £1700, treating for iron and sediment, plus a UV filter for sterilisation. All the above include vat.

We got around it with a special fire proof paint, we then just painted over it once we had sign off. Wasn't cheap and had to be applied by a certified by person to keep BC happy.

Air to air may put you off also. I lived with Aircon for a few years, and found it blowing at you all the time, even though it was supposed to blow in any other direction instead of you. Not sure hot heating would be much better.