JohnMo

They say eating meat is bad for you and the environment

Or just go AC coupled battery (with gateway), a normal string inverter for PV. You will need an earth spike. Then just operate in island mode. Once you have a grid connection take out of island mode. AC coupled will provide whole house with power. A hybrid inverter may only do a single circuit when no mains is connected.

Just had a look about and Rointe Onyx HHR Storage Heater don't look bad Stiebel Eltron SHS Storage Heaters - HHR but boxy but looks pretty clever. You should only need a couple, bedrooms would just be panel heaters anyway

If your weather is anything like ours you PV will be producing nothing. Just get your grid connection sorted.

Do you have two inverters or one and what make is it? You keep mentioning two different makes Is a string or hybrid inverter?

Didn't use anything really Use Excel spreadsheet to keep track of costs. Used Excel to build a plan, that was about it. What do mean everything legal is logged?

Or tee off the main pipe

Sorry with all that concrete in the floor I have no idea how the thermostat affects anything. You really are only opening and closing zones to keep some flow circulation through your 20+ loops at a sensible rate. Only 3x more than me.

We are at 192m² living space plus a large plant room of about 25m² so similar size wise, just bigger rooms as we are a 3 bed. We have 7 supply terminals, and 7 extracts. 2x extracts in kitchen seems over kill and 3 supplies also over kill for dining/lounge, 2x is ok. You don't need the one in the dining area at all, as the lounge ones will cross flow across the dining area anyway. Sweeping that area. Just up the lounge flows to compensate. Do you need the extract in the hall? Bed 2, 3 and 4 supply will over spill into hall, and that will be swept continuously, locate that extract to the 'hot press' Why spiral duct and not semi flexible? You will need a cross talk attenuator between each room with a branch system. If you go semi flexible you have a plenum and that handles cross talk for all rooms.

Why are you zoning and therefore needing to have a buffer?

Hope you aren't going the buffer route, and just do a single open zone.

So use something like this https://www.plumbingsuperstore.co.uk/product/hep2o-four-port-valved-manifold.html?gad_source=1&gad_campaignid=19088411016&gbraid=0AAAAAouuUvBBf8JjHjM-jpvt1ytEskuKZ&gclid=CjwKCAiA_dDIBhB6EiwAvzc1cIRTqTj3BAbhUmiDSZ9ZA72yeXC9NxZJomU3TMvJX9sYznUZNVbQWhoCuJoQAvD_BwE If the manifold is close to cylinder pipe in 22mm, if you decide to locate remote and more central pipe in 15mm from cylinder to manifold. I used one isolation valves per wetroom and branched in room itself. Other pipe to each outlet in wetroom with its own isolation valve.

In theory yes - in practice? Read the rules go direct to the BUS scheme wording so you know exactly where you stand. DHW and heating system are different things. I would have whole central heating system done as one event. Include the DHW cylinder install and then have a distribution manifold with an isolator valve for each wet room from DHW cylinder. Then central heating is all sorted, DHW you just open the valve associated to the wet room when wet room is completed.

Are you running high flow temperatures in thin screed. If not your floor will self regulate. In a low energy house, the floor temp is only going to be 1 or 2 degrees warmer than the room, most of the heating season. So solar gain naturally shuts down floor output. No need for a thermostat to do it for you. A floor surface that is at or equal to room temperature has zero heat output. A room that is warmer than the floor surface, the actually sucks heat in. If the floor loops are circulating this heat is absorbed by the heating water and redistributed around the house. We also have a similar house (we get massive solar gain in the shoulder seasons) we dumped the thermostatic micro managed system an age ago. Works way better without it.

Not always, many get a massive oversized charge for additional overheads that MCS requires. You also have a time frame from application to completion, to get the grant. If you are planning to run parts of the system in different stages, you are going to have add a buffer and live with the efficiency hit, to allow the heat pump to function correctly. Then when all the heating is in, remove the buffer. To get a piece meal system to function will take a little thought and planning.

What is the reasoning behind this statement. From what you describe you are going to need a big pay check to pay the heating costs. I would step back, post some details about your house and ask for suggestions Your proposal is going to end up a very poor performer and super expensive to run. Poor insulation in the floor (this is what you currently propose) when heating the floor is actually worse than no insulation in many situations. My solution would be ASHP, remove current floor to the concrete, egg crate panels (no insulation) and then 16mm UFH pipe at appropriate centre spacing. Screed. Then your stone floor finish. But do over whole ground floor. If you don't want that, dump the whole UFH project. And do your proposed plan for electric UFH only in bathroom on a timer. Then install modern storage heaters on E7 or better Octopus storage heater tariff.

So why do you need all these thermostats then? Not sure I have a read a single thread on here where anyone says Heatmiser are good, generally misreading, failing or not communicating.

Egg shells plus screed works. Do 16mm Pert-al-Pert tube. Insulated below at a higher thermal resistance to what ever is above the floor to ensure heat moves upwards not downwards.

Then you will add nice carpets and the output of the floor will be killed. Add fan coils for decent cooling in summer and to add heat in winter. Or radiators and run same temp as UFH or just add fixings for electric heaters, just in case you need! Just wouldn't bother with UFH.

That's what I did in the end, very helpful

Includes lamp and seal plus full clean of quartz, the lamp are £25 + £4 for seal both plus vat

1. Its maintenance, keep you flow rates as they are. You need balanced flow and extract with MVHR, but leave every as set at the terminals and tune fan speed to get back you your original or reduced rates if needed 2. Its maintenance, why do you need to tell anyone anything.

Is it a knock down and start again or do you need to reuse?

To get full instantaneous CoP you need dT, flow rate to get the work done. If you have a buffer you will need to take account of buffer distortion across buffer, when doing the calculation. You also need all the electric inputs, on the heat pump, any external circulation pumps both secondary and primary if you have them and power input to controller(s) to work out Watts of electricity used. All this needs to be accurate, rounded numbers are good enough. Just looked at the feeds and it's one decimal place on temperature and electricity and two places for flow rate.

Some really impressive CoP and SCoP numbers, but you really have to check them over, some on there only record some electric data, and miss internal units out, which is needed to actually calculate the CoP. Seen a few where the unit runs great and good CoP while running, but electric input stops with compressor cycle stopping, but the unit is still pump 10L/min, running the controller all at 1W input. Also while doing so recording a cop of of about 10. Other are getting a genuine SCoP of 5+. By using well sized units, tuned well and that modulate well and have super long run times. I have one it's great to actually compare what you think, and what real happens. You will be surprised how much standby time can kill real day to day CoP.