Dave Jones

they are re-inventing the wheel. We use a bog standard cylinder with an external plate heat exchanger. Heats 300L tank to 50c in less than 30 mins. Can also daisy chain more cheap cylinders as required for capacity.

point is you don’t need fall with a pumped chamber , they have a head rating. Also they come with a non return valve.

dont bodge it with macerators. pumped chamber is way to go.

the noise is a direct result of the pump having to work too hard. Get the house ready first. cart before the horse.

think of it as trying to only heat the top left corner of a radiator. The rest leeches form it and therefore requires more energy killing efficiency. Same with a slab. not rocket science.

i have an air nailer for fencing as coils of stainless steel nails are less than half the price of paslode. Run it off a dewalt battery compressor.

warranty provider will want it built NHBC compliant which means trays. If you have in writing from recticel that its ok not to use them and they will fully warranty your structure for damp then fair enough.

The dreaded cranked ceiling. No insulation there and sure enough mould grows. those cranks should have trickle vents , would 100% fix the issue

That’s fine but you are wasting efficiency for no gain.

as long as it has the minimum fall of 13mm per M, has no big (more than 30 degree) bends so it can be rodded. Crack on.

if you have had a BCO inspection then the permission has commenced end of conversation. If enforcement are soo thick as to challenge you on that, advise you will be appealing their enforcement (its free) and asking for full costs award. Unfortunately the public sector attracts utter failures unemployable in the private sector, knock them down a peg or too when you come across a really special one.

shed build unmortagageble unless very carefully looked after. Never worth it in our climate and market. In USA where land is cheap and they get blown over every coupl years make sence to cheaply shed build.

thats old gas boiler UFH design. You want 100mm spacing and every inch of the slab piped. No missing out baths, under cabinets etc. No zones either.

physically remove all the stats, any zone controls, timers etc. Get back to just the heat pump controller and set it to weather comp.

nothing stopping you making the usual repairs to the structure that coincidentally make it fully structurally sound at the same time adding some lean-to's increasing its footprint. All prior to planning, who's to say when any of that has been done 1 month or 10 years ago ?

the electric one is ok for occasional DIY use but are waayyy to heavy for daily use. Paslode all day long.

you don't have to actually build the extension to get the planning benefit, the council knows your PD rights. Go for what you actually want first. Get a planning specialist (not an architect) to do the application as they will make it appeal ready should it be needed. Appeals are free and give you 2 bites of the cake. Fallback is your current PD rights so nothing at all to lose.

Our council make it a planning decision condition to fit them.

we have 220m2 slab, this is new build so no historical data!

these are what we are using https://www.bpcventilation.com/panasonic-fan-coil-unit

maybe yout tank can take 2 immersions, can leave the boiler one as is and add another driven by eddi ?

Buffers kill efficiecny so no to that, have a LOT of ufh like 1.5km as its 100mm spaced which they tell me is more than enough so buffer not needed. Just cooling the slab makes a massive difference downstairs, basically any solar accumulation is negated. We have big bifolds which catch the sun all day, the floor would be very warm without it. Here is home assistant app, it pulls the date direct from the aquaera heat pump. The fancoils are not aircon by any means but cost virtually nothing to run as its only spinning a tiny fan through a plate heat exchanger. I left them on 24x7 with 16c flow and the bedrooms were very comfortable. MVHR we commissioning tomorrow, not expecting anything from the heat battery really but anything helps right. More for winter use.

It's the other way round. We have this exact setup working at the moment with 7 fancoils and UFH coil. We have the ASHP setup (we use Home Assistant to automate everything) to provide cooling 2c above the current dewpoint running 24x7. Dont need it for DHW as eddi and solar more than takes care of that. The fancoils (panansonic) can individually be turned on and off. Thy are just dumb radiuators at the end of the day all your controlling is a fan. Commissioning the Zehnder unit the weekend which has the intake cooling/heating battery also in the ASHP loop so will see how that assists as well.

use pozi's.

get an indemnity policy to cover it. cheap as chips