Nickfromwales

Send me your PayPal address and we’ll crowdfund the £7 ok

The whole point of these types of construction methods is to not require huge amounts of energy in the first place Agree the thermal retention is lessened re the walls, but who looks at storing and releasing energy to reduce heating costs in the context you suggest ( "quickly enough" )? In a Durisol / other ICF build, the mass you're referring to for energy stability is typically retained in all of the internal finish / fixtures / fabric layers not the core of the ICF. The 24 / 48 hr time period is what's important, so lets remember that heating up all that concrete in the first place, and then retaining the heat, takes equally huge amounts of energy ( which has to come from somewhere ). Having no requirement to inject that amount of heat in the first place = a low energy home. Add "mass" to add "thermal stability", but you still have to heat it and keep it there against it's will. Whatever kW of heat it emits will have required a greater amount to inject and retain it in order to facilitate that transaction, so concrete may be of benefit in certain targeted instances, but not in general, the same way an insulated passive standard UFH heated slab takes X amount of energy to stabilise it to ambient, then X amount more to keep it at ambint. To get the house heated from it then requires that original energy input plus whatever you require on top to maintain a comfortable temperature, plus losses.

Then the 'no dung' rule must be brought into play Upstairs for U571, and downstairs for #1.

Have a look at the MI’s as you can pump quite a distance with the turd crunchers Post a link to the weapon of choice, but agree to go for a pumping station and take the sink waste down to that to get rid of the macerator for the kitchen sink. Just on a hygiene POV I wouldn’t like to pump any McFlurry into the kitchen unit as that’s under immense pressure, and if it blew off you got yourself one fcuked up jet wash. ? I very much doubt SF would endorse that without an ‘open vented’ ( AAV capped ) pipe which would allow the McFlurry to fall to the second unit by gravity. Ew....

If not, the guys at PlasticSurgeon could probably ‘stretch’ it for you.

Can the wall be dry lined with a moisture resistant plasterboard and set out to fill the gap? Will the whole wall be able to be done so there’s no ‘step’ ?

Hi john Your post had been edited as we do not allow company / commercial links in new membership. ( It’s in our T’s & C’s ). Please ask the question of which exact type product / purpose etc you’re looking for and the other members can reply with suggestions. Thanks. Mods.

Second one, just for symmetry, but also you gain a bit more protection against the elements.

LVT should never go straight down, and I’ve never seen it done. The result would be terrible ?. Leveling with a feathering ( fine SLC ) compound is part of the installation as a rule so that cost should be lent to the laying of the flooring and not reflect on the total cost of the screed . LVT is simply too thin to even dream about putting it straight into a slab. You even have to plywood and feather over chipboard / other timber decks prior to LVT going down.

I’m not sure what they put in the curry in Dorset, but I think most of it was out of date. ? ?

It’s not just the obvious heat emitted from the manifold, but also the M25 of pipework that’s in the immediately surrounding floor too. You’ll not just have the heat from the manifold, but also the hottest section of floor in the entire house, all in the confines of the panty. Can it go somewhere else?

Sue. We have a pipe decoiler in our Buildhub tool loan stock. Let me know when you are ready and you can reserve it. £10 donation to the BH coffers is the price, plus P&P to send onto the next 'borrower' or to return it to a staff member to hold.

You can simply add something like this and set the overrun to suit. Boost will stay on until the hood is turned off, and then it falls back to overrun timer which you set to suit. Link

Can you give a little more detail on how / why you need the boost to work please? I would imagine ( yet to fit my first unit ) that the boost goes into overrun itself so any external trigger / feed should only need to be momentary.

If that post doesn't answer the question, then not much else will

The Ivar doesn't rely on returned cool water to function and does not 'have to have' a return to operate at all. The opening of the valve, for heated water to be introduced to the recirculating UFH loop water, relies on a thermo probe which sits in a wet pocket and references 'post mix' flow temp. That connects hydraulically via a capillary wire to the valve which operates like a TRV radiator valve. The temp is very reliably controlled and you can operate at temps as low as 20oC and as high as 60oC with near pinpoint accuracy. I've ditched the TMV blending sets altogether now, particularly for 'passsive' builds where temperature hysteresis is critical.

What word do YOU use when you get to the end of a slow, careful mitred cut and the last inch of the limestone splits off and flies away into space?

Would be exactly the same for a cylinder All these things either need sizing for the worst case scenario or a means for boost under duress incorporated accordingly.

This refers to my 'perfect storm' scenario I'm afraid, and reiterates the need for installer to specify not Mr Smith. ( Jeremy, please set aside the fact that you're a knowledgable chap and permit me this as a generic response or we'll be here all day ). For pre-heating eg excess PV > SA > gas combi I would always go one size under if I thought a bigger unit would be part redundant. I oversize if they're the ONLY means of getting DHW, therefore Jeremy I would have suggested a 12 for you based on 24 hours usage not the morning and evening events as I know it would have had enough charge to get you through 24 hours and there would have been no need to explain my reasoning as you'd be the customer and I would be the designer and installer. Even though you can discipline yourself to use the same amount of DHW each and every day, I would never specify that close to the wind as when guests come to stay you'd be outside the bathroom door with stopwatch in your hand. No customers of mine want to buy into that, but admittedly it 'can' be 'overcome' by hitting a "guest" / "boost" button as and when required. That however is not 'fit and forget' and is only done by prior agreement as a caveat, eg I cant get my arse chewed over it then.

Yes, in essence, but I would not go to 2x 9's I would go to 1x 12. A 9 is equivalent to a 212L UVC, and that is fit for most domestic homes with the Smiths and their 2.4 children, so a 12 would be ample. I would only go to 2x x sized units if the DHW demand was high and then the SA would out-perform the equivalent UVC hands down, plus to answer @PeterStarck's question fully, there would be no pressure reducing valve, no cold mains pressure relief valve, no temp and pressure relief valve, no D1 and D2 overflow / discharge pipework, no G3 installation criteria and zero ongoing G3 annual inspection ( for the life of the U|VC ) which would equate to a saving over 20 years of around £2k minimum. A proper G3 annual inspection should comprise of the draining down of all of the hot water from the tank, then a witness of the tank reheating and the control valves / thermostats all shutting off accordingly, then a manual test of the PRV's ( which makes the bloody thigs start leaking / passing water so any installer will refuse to touch them without that caveat in place ), and then a full visual inspection of the D1 and D2 discharging to waste...…...followed by isolation of the cold water supply, draining off of the head of cold mains pressure, then the checking of the pre-charge pressure in the 'gassed' side of the expansion vessel to ensure the EV is in good order / the bladder hasn't ruptured. What a damn ball-ache!!!!!!! Anyone who does any less than the above has NOT carried out a proper G3 annual inspection and you should not have wasted your time and money getting them out I the first place. I know of one landlord who was left with a £30k bill when his insurers failed to pay out because of a failed maintenance / installation instance in a block of flats where the two flats below were flooded. UVC's are constantly losing charge in the expansion vessels, which needs annual checking and topping up, and I've seen the aftermath when owners shrug off that routine where the UVC pops and floods the house. Greater still is the fact that most are upstairs and even greater again is the fact that thy are connected to the cold mains so have an infinite supply of mains pressure water to spew out until you get home from work. To answer it specifically, the sheer size of the equivalent 440L cylinder? 2 x size 9 units would still fit under a kitchen / utility worktop whereas that cylinder would be roughly 1800mm high x 660mm diameter. The cost of 1x size 9 SA ( ~£1800 depending on which model ) would pay for the 440L cylinder. In 20 years the cylinder would have cost more to inspect let alone buy.

Nonsense.

Not exactly what I said. So, to further clarify; As an installer and a person who has an active interest in SA I have put myself forward as an installer. As an installer I have deemed BY MYSELF that there is an effective workaround to the 'issue' that only @JSHarris has currently highlighted ( please inform me if there are others who have stated this EXACT issue as I am not currently aware of any other like instances ). I have not been told to do this by SA and they do not see an issue at this time. I have had an agreement from SA that it is always best to be cautious when sizing for capacity, so the above is MY take on how the units should be sized and implemented. SA have not 'recognised' anything of the sort and I very much doubt they'll change the entire fleet over what is from their perspective an isolated case. What the facts are and how this has been identified as problematic extend to my comment about the perfect storm. That is apparent in many technologies and is simply an instance here as highlights a weakness created by this 'feature'. For you tin hat I say what about all the others in, working, and without complaint? I oversize everything in all things I do, because incrementally it's a safe bet. If someone is to give £1600 for a 6 which may just do it, then I would not entertain fitting it unless they went with a 9. same goes for the 9, if its borderline then I'll recommend a 12. I do the same with radiators and gas boilers, as you can turn a big radiator down but you cant turn a small radiator up.

Pretty much. That statement I made was a little 'broad', as I have made no such consideration in the instance of the property with both a 3 and a 6 ( as they were already on site when I was asked to go and fit them ) and the 3 is currently. However, I will add that those units were being fed by grid electricity on demand and when the client gets around to fitting his PV diversion controller which I think is now done tbh I shall be in contact to get some feedback ( if they don't contact me first that is ). In fairness, if @JSHarris had a teenage daughter and 3 showers were drawn every morning / nigh time then the likelihood is that this thread wouldn't exist. It's only because the sizing and the usage of DHW have created the perfect storm that this is apparent, so is actually focussing on the weakness not the strength of the SA controller. Take for eg the install with the size 9, with two adults and one child, who I have not heard one peep from since leaving. They clearly live the other side of the 50% difficulty and Jeremy lives t'other. I wonder if there is a way to convey the fact that there is export occurring to trigger the timeclock / low current interrupter so that it bumps the SA into 'hunt' and it would then scoff up any excess.

Yes, all chat to date has been about air to water HP's. The one that's described above, the r-prefix, takes F-gas directly into the SA heat exchanger to melt the PCM directly with the energy produced by a dedicated HP. The idea being that the whole setup doesn't suffer the losses of going air-water-HEx eg the losses of the conversion in the HP and also the losses downstream of the hydraulic circuit in between the two units. In honesty I have not asked recently if these units are to market currently. I shall enquire though as I did like the idea when I was made aware of the principle some time ago. The PCM58 needs a flow temp in excess of 58oC to melt the PCM, so a 'regular' ASHP is no good, as it's probably going to max out at 58oC at the HP ( at which point the CoP would be in the gutter ), and then the losses in the hydraulic circuit will see less than that actually arrive at the SA. The SA's I've seen working with HP's so far have all been high-temp heat pumps which give 650C to the SA. These HP's have also been doing space heating via upsized radiators with some iirc storing off peak produced energy for space heating between off peak events. Like I said, tin hat

Exactly the conversation I had today. It needs to be implemented to make good use of it's capabilities, and today I told someone that it would be best to simply switch it off for 3 or 4 months of the year where there would be insufficient PV to charge the AC batteries AND offset the house base loads eg during peak winter.