Nickfromwales

It makes no difference tbh. If the person laying the concrete is also paid the likely costs expected from the secondary liquid screed layers, then when combined you can likely afford the best concrete flooring company around ( so they'll get it nice and flat ) The question is a bit perverse as to fear the person doing the concrete incorrectly means you have no confidence in their capability, so dont use them and just pay once to a single contractor to do the concrete properly first as last. You really dont want a 150mm slab, as 100mm is typical, but IMO 120mm would give a nice storage heater for a dwelling thats inhabited ( or needs to be at temperature ) most of the 24 hrs in the average day. Easier to keep warm and a bit more heat capacity to see the ASHP's only consuming off-peak electricity out of sunlight ( PV ) hours eg at night with the slab acting as a buffer.

Best to warm the manifold with a blended HRC circuit imo, and remember it can be timed so not running 24/7. For one client I have designed the HRC to switch on and off in line with the burglar alarm so when armed ( out or sleeping ) the HRC shuts off. Make sure the cold feeds to the kitchen / utility / baths / showers are done in 15mm NOT 10mm. They’ll struggle in 10mm. You only want 10mm to ( optional ) the WCs and the hot taps on basins / sinks. Oops lol. ?

With 2x12kW PCM58's you'll have about 27kWh of heat capacity and 6kW of electrical input so as long as your peak space heating demand doesn't exceed the 6kW then you'll be fine. DHW will come from the redundant capacity that will reside in the units, when they're fully charged. I imagine they're both 'eDual' units, so basically both units can lend either space heating or DHW to each other for maximum ( combined ) effect. I doubt you'll go wrong with that setup unless your in a draughty 1980's build with single glazing. For the kitchen run, can you not chase a pipe into the floor and insulate it? Then your as the crow flies and will reduce that run significantly. With that kind of flow rate and pressure you could easily run the kitchen hot feed in 10mm for even more reduction in 'delay to tap', plus its a no brainer to dos the same with all the other hot feeds to basins / sinks. Get over the extra 1 fitting each end of the run, but TBH if you shop clever you can even reduce that. 10mm x 1/2" male straight to the Flexi . "Just do it man !" All other cold feeds to be 15mm All other hot feeds to be 15mm On that basis, the plan seems a good one to me. The reason for a HRC pump on even that small a setup is because the manifold introduces a primary pipework arrangement which needs to be all 22mm, eg from the SA units to the manifolds, then the manifolds themselves are 3/4", and then the small bore 'distribution' pipework starts from there. You otherwise must factor in having to discharge all of that 'dead leg' of DHW prior to it getting out of the desired outlet so think twice about a HRC as it does make a big difference. Eg to run the upstairs basin and get hot water the water must travel out of the secondary SA unit ( the heat exchanger will be hot already as the SA's are instant water heaters ) and go through the interconnecting 22mm pipework prior to the manifold, and then through the manifold, before the reduction in the distribution pipework has a chance to carry out its intended function ( to reduce the volume of water two discharge before getting premium temperature water from the chosen outlet ). At the least, and as a start point, I'd fit a Grundfos Comfort HRC pump to simply circulate between the SA's and the manifold, so the primary arrangement was always 'at temp' and ready to deliver. Remember that having great pressure and flow will be of little consequence at the basins as you wont be able to run them very fast without getting splashing water everywhere ( if that was assumed in an attempt to discharge the dead leg ). Basins exaggerate the problem because typically they are outlets which are used 'little and often' and therefore anything even slightly excessive lengths in the preceding pipe run can see you washing your hands before hot water has arrived. The Grundfos Comfort is a very energy efficient pump so is not quite the 'extravagance' that some may see it as. Compare a house that has it to one that doesn't and you'll soon warm to it.

He's close to sticking them on. Good enough for me. ?

Just change it to a "waterless" trap and have done with it. Anythihg like the hepvo traps.

?????

The reason being? If you don't put it in id think your were nuts tbh. Its 100% the best option without a single doubt. Any waste run over 3m should be designed out, let alone a vertical drop down one floor level. No deal Noel. ?

Only for you, pal.

Excellent progress. I hope the plumber doesn't hold them up

I'd say yes if larger bore radial ductwork or radial ductwork with multiple room inlets are used. Eg higher flow rate, less noise, better dispersion. Where problematic I'd look at low level plenums. Would also lend itself to not having taller 'beefed up' joists aka ????

In a perfect world yes. The issue is where the nails are not driven completely home and there is insufficient glue at that point. The squeaky floors that folk recount are where the deck board moves up and down the shank of the nail. Thats why where @jack's better half screwed alongside each nail, the boards have pulled down tight to the joist top and the slight movement has been removed, ergo the squeak has gone . Glued and 5 screws per joist for me every single day of every week. The floor im doing now Sistered timbers either side for levelling ( retrofit on a turn of the century house ) then 22mm p5 D4 glued and screwed as stated. Then for tiling over, 6mm plywood laid into a bed of neat PVA ( 3mm notched spreader ) and screws in at 120mm centres on the X & Y axis. Customer says it's like the ground floor room now which is concrete. @vivienz as you will be having aluminium spreader plates for 1stfloor UFH, a mechanical fix will be mandatory as you'll have little to zero timber > glue > deck surface area to allow that method .

If its that noisy, and your as sure as you can be that its coming from the HP coil, then too damn right. What if it gets worse? The last time I had a warranty claim with telford, prob over 8 years ago ( and not really a fault more my blagging as the EV had gone and popped the UVC ) they dropped off the new one and waited to collect the old one.

Return it as faulty

Was this purchased new in the BH-Telford 'deal'? Ask for it to be replaced.

Yup. Smother them to death and then wipe any excess off with the cheapest baby wipes you can find, lots and lots of them. Buy a can of CT1 Multi-Solve spray to do the final spit n polish. Pump the bastard stuff in there and watch it ooze out of everything. You could seal a submarine with that stuff. Dont be tight or you'll be doing it again, and dont forget that when you put it in the next time I doubt you'll ever be able to get them out intact again so 'one shot' or 'deep shit'.......

So where is the CT1 ? Under the T against the top of the upstand?

Double 'r' folks, aint that right @Garry Oh, and welcome aboard !!

Nope, hes probably designing a machine that makes machines........in his spare time.

Do not cut into the structural 'silicone' if it forms part on the unit. Are you referring to a bead of silicone that the upstand is bonded to that was retrospectively applied by your delicate hand?

Not very fackin well

Has anyone actually given you detailed installation instructions?

I think this may be a candidate for just CT1'ing the shit out of it where the upstand meets the underside of the window.

I think this is the important piece of this particular 'puzzle'. For a smaller, or certainly a single storey dwelling, the heat loss is far more manageable and therefore requires much less effort to offset it. Could you just remind me of the exact makeup of your ground floor from the earth up please? I am very interested to hear that you find the stability and relationship between the floors / walls / windows all seem to be relatively indifferent, and I assume this is attributed to by not turning the 'heating' off for any extended periods, instead favouring long low heat influx via the Genevex. Also, do you have an indication of what temp the dwelling will naturally reside at if you shut the heating off ( eg what was it performing like prior to commissioning the heating and setting it to work ) ? Sorry to keep singling you out Peter, but yours is an interesting case study and examines the possibilities that lay away from the generic lines of thought. The case I referenced is manageable, with the points I've highlighted vs the crap that the MVHR supplier first spewed out without proper review, but does indeed require auxiliary emitters to achieve it. Me personally, I'd have gone for wet UFH in plates because thats the entire ground floor done and dusted, plus they require wet heating to supply the bloody feature rad and towel rads anyway so my thoughts are that in a bigger dwelling its a bit perverse. IMO MVHR should be left to be MVHR, with just the selective addition of maybe a 'geothermal' brine loop for some passive energy input. In a PH you're never that far away from comfortable and 'climate control' should remain within reasonable grasp ( if you haven't made a greenhouse with all the glazing that is ).

Sounds like drainage is your issue. Should you not be putting some kids no of permeable upstand around these and then paving to that? Possibly something that looks like a brickwork weep vent on its side ?

Post it up .