Nickfromwales

Only if the defunct heater is physically disconnected, or else it’ll inevitably heat up from the physical connection of the heated pipework; it’ll just turn into a radiator at that point, no?

One person who used to install these things, back in the day, is now pretty much left without some functioning vertebrae. Sad demise of someone who was entirely invested in this product, and another casualty of SA’s insatiable appetite for success under duress; setting aside the paying public Guinea pigs that is (or “casualties” as I had ultimately decided to refer to them as back then). Zero health and safety considerations from SA, even for their own staff, and zero thought of how these things were to be moved safely from A > B. I remember my dad, who owned a vending machine company, having one of those forklift type stair climbing things to move 6’ tall machines independently. That was over 30 years ago, so the fact that SA happily left staff without these things, post Y2K, is another demonstration of just how profit hungry and utterly disrespectful these owners are. I guess you only become a multi-millionaire by putting yourself first.

I’m glad you clarified, now I can sleep…

On a recent project I just used 1" 8's with small washers and a very long bit holder in the impact, as access was a bit tricky. I've posted on here about stapling up from the underside, again into 22mm P5 Egger, and I did that with an air-powered stapler, and 10mm staples, which worked a charm. More the merrier, and the air stapler made it a quick and easy task.

Is this external or internal? Most flooring suppliers offer a range of aesthetic collars / cover rings in many different colours and sizes. Maybe try looking there? Most are MDF I think, so at the least you'd have to spray them with a lacquer to make them weatherproof. How nice do they need to be?

You'll need to do all the local pipework with compression fittings, which are all very comfortably / easily accessible, and only then would this be practically 'moveable' in the event of it's early failure or......well I can't say service or maintenance as these things USP is supposed to be that they don't need any I would suggest you get some 20mm steel conduit, galvanised, cut it into 450mm long pieces, and just go full out Egyptian with it. Would need these all tight together with no gaps to spread the weight, and not distort the case, but I'd check with SA to see if that would yet again be "a non-standard installation" that would void your warranty You are deluded if you think the SA can be anything other than floor mounted? Even more so in a confined space. It's a genie lift job for something like this, and if it ever fell on top of someone then the are brown bread mate. These things feel as if they are full of dark matter... @Jeremy Harris what say you on these being installed, elevated, in a confined space, in an apartment?

The scientific answer to that, is, I just forget who’s building what and reply here sporadically….lol….but I tend to offer free advice with an assumption that covers the worst case. 20,000+ members on here now, and I am so busy I can just about remember what colour shreddies I am wearing. The 24/7 setback stats can (usually) be set to ‘manual override’ too, which ticks every possible box.

Nice neat install

https://www.cylinders2go.co.uk/shop/stainless-steel-unvented-cylinders/unvented-horizontal-cylinders/telford-tempest-125-litre-horizontal-direct-unvented-cylinder-2/

“Bugger”. Bath?

Can’t you fit a 15/20/30l water heater under the kitchen sink, and do an electric shower? Is there a bath to fill?

Is there 3 phase available there? The 27kw Stiebel Eltron instant water heater is just absolutely amazing. Its water production is that of a good combi boiler, I was super-impressed by this. If you can convert the supply and fit cost of the Sunamp / Thermino (prob north of £8k installed with electrics and plumbing, including the new D1/2 PRV discharge waste requirements etc) and buy one of those instead, for IIRC sub £600, then use the change to get a 3ph feed to it, that would serve you well, and it’s the size of a larger, taller shoebox!. https://www.heatershop.co.uk/stiebel-eltron-dhb-e-27-203865-set-three-phase-touch-instantaneous-water-heater-3i-technology?gad_source=1&gbraid=0AAAAAD_r406R6I3CsDg1Re8V-Esxh4jxz&gclid=Cj0KCQiA4rK8BhD7ARIsAFe5LXIpAgmiAiYnFIbawprfNVfL4unFAqqJbdCD4n9dl7E5-UGEgCIJ2KoaAv4wEALw_wcB

It’s down to opinion unless the BCO is called to site as a complaint? It doesn’t have to look pretty to be functional, in a nutshell. Damp course being bridged = not your concern…perps missing or poorly executed = not your concern… If it falls over and squashes you, then it becomes your concern. You claim on their insurance, after the event. Once the fence goes back up, do you actually care about this? I can’t see why you would, but if it’s an eye-sore then just add a trellis header to the fence and worry about things more important to you? Please don’t read that as me being sarcastic, I am not, just perhaps a reality check and taking you off the boil to reevaluate

Then the fail rates change and it becomes a “lead & lag” arrangement, meaning one heater is doing the brunt of the work always. Not how I design these things. I design this so that the 2x Willis are “the heater”, with a 22mm flow in, and a 22mm flow out, and end of. I’d have to ask why anyone would want to complicate such a solid, simple, reliable setup which already promotes huge longevity? Especially when it’s in, fitted, commissioned, working, and not defective at all?

Yup. We’re just wasting time discussing a problem that doesn’t exist, unfortunately.

@Onoff the reason for fitting these in parallel is explained to the T in your link, thanks. For the benefit of other forum members: When I fit Willis heaters in parallel I make sure the pipework to each unit, in and out, is hydraulically equal (same pipework distance and size). This does indeed maintain equal flow through both units, and the notion of any problem created by “mixing” within ‘the heater’ is a dreamt up issue at best. You don’t see domestic clients pull apart a new W-Bosch combi and start adding valves to their plate heat exchanger internals, saying “some pathways are slightly hydraulically different”, do you? Fact is, cold water goes in, and hot water (the product of the various mixing characteristics of the PHE internals) comes out the other end……🤔 Literally couldn’t be easier….. The input temp vs output temp is what you reference; simply getting the sum in / out values and indeed then allowing the heaters to do the work as they were designed to do so. If however the design is hydraulically imbalanced, then flow would go through one heater more than the other, which is why I don’t do that. A lot of micro-managing type folk have discussed this with me, in other instances, unfortunately LONG AFTER THE DESIGN AND INSTALLATION HAS TAKEN PLACE AND THEY’VE HAD EVERY OPPORTUNITY TO ASK QUESTIONS UP TO THE POINT OF COMMISSIONING, often to criticise or question (more so when another plumber has been approached in the interim for a random uneducated opinion on this AND HAS GOT IT WRONG). More annoyingly, in another instance, a complaining client I installed such a system for had posted on a public forum to say the system that I installed was working “too well” if anything, but then went on (when bored and over-thinking everything as usual) start attempting to pick faults that didn't actually exist, complain about hypothetical problems, ahead of them ever occurring / or having had actually occurred, but this is almost always simply the unexplainable and irrational nature of some people. Hydraulically, a pumped system, such as the OP’s (may possibly(?) be) will be primarily piped in 22mm copper, and the Willis heaters are 15mm in/out, therefore these would then be a choke point; if, by design, the system installer had to account for the system to be able to cope with any adversities (and be reliable) then adding 2x in parallel would give 30mm of hydraulic pathway visible to the 22mm pump body therefore allowing it to enjoy minimal resistance and live a long happy life. I assume any “pro” plumber, perhaps not the original installer, if the aforementioned alterations were not bodged by the homeowner, would have made this observation before hacking into a perfectly working already installed system, and there would now be a PBV teed into the flow out of the pump and back to return to cope with the change in hydraulic difference, so as to not labour the pump. Not heard any mention of that, just isolating valves, so this is probably now to the detriment of the originally design-in longevity and reliability. Cool. Only joking, completely uncool. Irony is, that would then constitute a mixing effect, but if that design came from a “pro” plumber….then that would be ‘all fine and dandy, I expect. Just grabbing at straws here btw, so please don’t take any of this as factual, and please don’t quote (re-quote) me here as I have no clue as to what I’m doing, (via my inconsequential 30+ years experience of plumbing / heating et-al), just pure guesswork which you should all ignore I once was asked, in another instance, about doing this, and I went on to explain in detail why putting 2 in series was (IMO) a terrible idea, and that person agreed and I carried on about my business. System still works perfectly well to this day without complain or defect (Passivhaus type dwelling with an insulated raft / airtight / MVHR etc etc). As per the internal PHE of a brand new combi, in another similar instance, I suggested that the client leave it the fcuk alone and enjoy the heated water that comes out of it reliably, and as per its intentional design, as it’s worked for everyone else that has one like that….. “If it ain’t broke, then don’t fix it”. I disagree. When I plumb in Willis heaters like this, I have 22x22x15mm compression Tees where the 15mm spurs face forward. The Willis heaters compression fittings push back onto these spurs and job done. In the event of failure the 2x 15mm compression nuts get loosened off the T, the new Willis adopts the 2x reusable spurs and the lot then gets remade back as original (no cutting of pipe etc, just 2 or 4 new 15mm olives needed at most). 30 mins drain down / swap / back to work is my design methodology. When I design whole of house M&E systems for self build clientele I always factor in this discipline, eg I plumb it to make downstream service / inspection / replacement of components that we all know will eventually fail, easy to do and 99 times out of 100 without anything other than a towel and a spanner, just as any “pro” installer should.

Indeed, but he’s a grown man so just let him carry on about his business please, I’m sure it’ll be fine.

My go-to ASHP guys used these (2 different companies / installers) and on both jobs there has not been a 100% success rate, but to be fair this can be said of any soldered joint or compression joint; the big difference is when the bastard requires a huge effort and chopping out of a lot of the local pipe etc to change it which winds me up. Even a failed soldered joint can be successfully re-sweated in situ in most instances, and compressions can be removed, olive changed, sorted fast and that happens without touching anything more than a spanner. Not an issue for me as the companies both returned swiftly and made good where it was critical to do so, at their cost, but if it is a compression joint then it just needs a pinch up. Press-fit is used everywhere these days, because of its speed of installation and its relative simplicity, but nothings going to be documented here that is 100% guaranteed leak / bomb-proof as mostly it's either a manufacture defect or installer error that produces a failed joint, and that's never going away regardless of the system or product types; just called "life". The reason I stick to compression / brass / copper in all plant installations is that it has never really let me down, but I am very attentive in my workmanship (for good reason) as I would have to travel a considerable distance to facilitate a service call for such a failure which would sap a lot of the profit made from the job.....hence I try and fill & test when I am at the hotel and make sure I am back again the next day doing X/Y/Z meaning I am able to observe the plumbing to check for leaks before packing up and heading home. It doesn't always work, such is life, so one weeping fitting is not the end of the world in actuality, and you could have called the chaps back on warranty to do the repair for free? Was probably your nature to take the path of simplicity and speed, eg do the bloody thing yourself as it's quicker and easier, and you have the skills.

Why wasn't the fence taken down and permission given for access, eg so they had a fighting chance of doing at least a better job than that?

Ah, so I’ve been starved of this critical and vital information until now, yes? lol It’s ok, I forgive you. As with everything the devil is in the detail, so please give us the entire picture so we can advise correctly and swiftly, kind sir.

Lol. If it ain't dry by now it's never going to be

I'll drop the wife's hair straighteners in that, poke 3 holes in the top, and name it "Sanump". Dragons Den here I come.

Nope, it's the insulation panels which are vacuum sealed jobbies, as in the best bang for the thinnest footprint. 👍

I’ll chop it up and give it to the crackheads down the train station. 👍.

Met a chap at a public show who’d just paid £14k for 2x Thermino 210 units (replacement names for the old 9’s) and I almost keeled over. WTF.