Sunamp failure - NOW FIXED!

[Jeremy Harris]

33 minutes ago, SteamyTea said:

Can you get it analysed to find out what is in it. We have a lazer spectroscope thinking at work, not sure if it does all chemicals or just metals, never tried it out.

 

I could post you a lump of it easily enough.  I've got a few bits sat in a box here from the big icicle of the stuff that formed down the rear of the case.

[DamonHD]

I'd quite like a small lump to sit on top of my Thermino, maybe to instill a sense of mortality in it!  B^>

[SteamyTea]

1 hour ago, Jeremy Harris said:

I could post you a lump of it easily enough

Going up country tomorrow, so almost passing your place if you are about.

[Barney12]

3 hours ago, Nickfromwales said:

 Bean-counters prob won’t like the materials or manufacturing costs of that solution methinks, but for north of £6k for supply and fit, there’s should be enough frigging meat on their bones…

if you take a deep dive into their accounts (yes, I know I’m sad but I’m blaming the jet lag). They are all bones and no meat ! 

[Jeremy Harris]

34 minutes ago, SteamyTea said:

Going up country tomorrow, so almost passing your place if you are about.

 

We've got a couple of things on tomorrow, but if you know roughly when you might be around I'm sure I can be in.  Not sure how big a lump you would like, this is the largest of the  bits I've kept:

 

[Nickfromwales]

44 minutes ago, Barney12 said:

if you take a deep dive into their accounts (yes, I know I’m sad but I’m blaming the jet lag). They are all bones and no meat ! 

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. 

[Nickfromwales]

2 hours ago, Jeremy Harris said:

 

I could post you a lump of it easily enough.  I've got a few bits sat in a box here from the big icicle of the stuff that formed down the rear of the case.

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

 

[Onoff]

Around £230 for 25kg and it comes with it's own plastic containment vessel! 

 

 

If there's space for expansion inside the Sunamp then how does it expand / rupture?

 

For some reason I always thought the PCM was contained in a vacuum, is it?

[Nickfromwales]

13 minutes ago, Onoff said:

For some reason I always thought the PCM was contained in a vacuum, is it?

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

[JohnMo]

6 hours ago, Onoff said:

Thinking 316 (marine grade) stainless would be ok with the "salt" that is the SAT

Not a good material, as when in a saline environment 316 or 316L suffers pitting corrosion especially at or close to 60 degs. So you really need super duplex or even titanium. So not cheap.

[Nickfromwales]

15 minutes ago, Onoff said:

Around £230 for 25kg and it comes with it's own plastic containment vessel! 

 

 

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.

[JohnMo]

15 minutes ago, Onoff said:

Around £230 for 25kg and it comes with it's own plastic containment vessel! 

 

 

If there's space for expansion inside the Sunamp then how does it expand / rupture?

 

For some reason I always thought the PCM was contained in a vacuum, is it?

Think if you mix with Agar Agar, the solidification process becomes more repeatable and repeatable over time

[Jeremy Harris]

Worth noting that although sodium acetate is chemically a salt, it's not very reactive, in fact it's used as a neutralising buffer for sulphuric acid to stop it being corrosive.

 

The reason table/road salt is so reactive is because it's a chloride I think.  Halogens want to react with anything and everything, hence the reason that swimming pools are evil environments for anything that might possibly corrode.  Chlorine will attack a very wide range of materials, even at very low concentrations.  I made the mistake of leaving a 5 litre container of hypochlorite path cleaner in the shed.  The lid was on tightly and the container was in a plastic bag, with a cable tie around the neck, as it had been shipped,  It wasn't leaking but the miniscule amount of chlorine that escaped was enough to surface rust everything in the shed within a couple of weeks.

[Jeremy Harris]

2 hours ago, DamonHD said:

I'd quite like a small lump to sit on top of my Thermino, maybe to instill a sense of mortality in it!  B^>

 

 

I can post you a small lump if you want, Damon, might be a bit crumbly as the one big lump is that bit I've promised @SteamyTea. 

 

Not sure if I've still got your address, though, perhaps you can PM me if you'd like a bit to threaten your Thermino with, to make sure it keeps behaving itself. . .

[Mike]

5 hours ago, Jeremy Harris said:

My gut feeling is that for not too much money it would be useful to have a standby hot water system, even if it only has a modest capacity.  Even a 3 or 4 minute hot shower would be a heck of a lot better than no shower!

I have just such a system: one 20L electric tea urn + a rechargeable camping shower - total cost around £100, no plumbing required :)

[Jeremy Harris]

17 minutes ago, Mike said:

I have just such a system: one 20L electric tea urn + a rechargeable camping shower - total cost around £100, no plumbing required

 

 

Funnily enough I ordered one of those USB rechargeable camping showers 2 days ago!  To get warm water for a shower I put together a Heath Robinson arrangement using stuff I had around, two spare 20W, 12V silicone rubber heating mats (I had to buy four when I only needed one for a bag warmer), a 6A, 12V power supply and a couple of 5 litre lidded buckets.  This worked very well, the heaters were plonked into each bucket and left on all night.  By the morning we had two buckets of water at around 38°C, which was fine for  a sort of cup-over-head type shower.  we could have filled them from the boiling water tap, as the boiler for that holds 20 litres, but that would have meant carrying the buckets upstairs, which seemed like too much effort first thing in the morning!

 

The bucket warming experiment, before I set them up properly upstairs:

 

[Onoff]

ChatGPT suggests SAT will have a minimal effect on stainless steel, particularly 316L )in part due to the absence of chlorides as Jeremy mentioned). So it's salt Jim but not as we know it!

 

https://chatgpt.com/share/678b5bfc-67dc-8006-abdf-68dedb82e418

[Onoff]

This whole Sunamp failure seems a case of someone with a clever, clearly workable PCM formula not appreciating or understanding real world materials behaviour in the case (pun intended) of the containment. The hand stirring it is probably the bean counters. If I recall correctly the product was at one point value engineered for the mass market. 

 

I've been fixing, modifying and providing feedback on bespoke kit for a living for nearly 30 years. Designed by chartered & software engineers in a warm office who didn't realise "it" would (or more often wouldn't) behave like that in the real world. 

 

I know plenty of God like TIG welders who make swirl pots and custom fuel tanks in their sleep / for fun. 

 

I personally would construct an outer and inner stainless shell. After fabrication the space between the two would be filled with "expanding foam". That would require careful welding of braces to limit unsightly swelling. 

 

It could be done. Heating elements, pressure relief valves & thermistor stacks could be replaced from outside the shell. As aforementioned the PCM could be filled via a screw cap perhaps even with a low point drain to assist replace replacement. Totally doable imo. 

 

It's only time, money, knowledge & ability stopping me...mainly just the last 4! 

Edited 4 hours ago by Onoff

[Onoff]

I can tell stories about corrosion issues with a famous stainless barrier across a famous river...but I won't! 😉

[Jeremy Harris]

If the container(s) were cylindrical, rather than rectangular, I suspect many of the structural issues (if indeed these are key) might just go away.  One of the slimline wall mounted UVCs I've been looking at is slimline because internally it has two smaller diameter cylinders mounted side by side inside a rectangular case, with the gaps between the two filled with foam.  Part of the efficiency of the Sunamp comes from the vacuum insulated panels, which have to be flat I believe, but they could still be used with a two, or three, cylinder design within a rectangular case, with the internal gaps filled with foam.

 

The size of the units would increase a bit, but not by that much.  I've been doing a comparison of the wall-mounted UVC options  and the slimline two cylinder ones are only a wee bit taller than the cylindrical ones for the same volume, but are about half the thickness/diameter.  Depends how critical dimensions are when marketing these things.  I'm looking at them as someone with a tight width and thickness limit and a not so tight height limit, others might view things differently. 

 

Most of the Sunamp installation photos I've seen online don't seem to be in particularly space sensitive locations.  If I had to guess I'd say that height may well be the most critical dimension for many, so it may even be that a cylindrical unit that's about the same diameter as the length of the existing units (they are all the same length and width, they vary in height) might be acceptable.

[Kelvin]

Not read all the posts but was thinking about the salt leak when plumbing in my dog shower yesterday. Shouldn’t the unit sit in some sort of containment tray in case it does leak. Chemical storage tanks often have bunds built around them for example. 

Edited 4 hours ago by Kelvin

[Jeremy Harris]

1 minute ago, Kelvin said:

Not read all the posts but was thinking about the salt leak when plumbing in my dog shower yesterday. Shouldn’t the unit sit in some sort of containment tray in case it does leak. Chemical storage tanks often have bunds built around them for example. 

 

I'm doing this with the replacement, it's mentioned a bit further up the thread.   One problem is that these units are very heavy, our old unit weighed 155kg, the new one is slightly heavier I believe.  This means it would be very difficult to lift one over a lip, so I'm just making the edge boards watertight by sealing them with sikaflex to the base board, after the unit has been slid into place.

 

[Kelvin]

Just reading that now. The other observation from your experience is installation location is crucial too which is true for lots of elements of a house build. You need to assume that a thing will fail and, if it does, how to access it after the house is built around it. 

Edited 3 hours ago by Kelvin

[Barney12]

13 hours ago, Nickfromwales said:

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. 

Here’s an extract from their accounts. Some impressive numbers which perhaps underlines that self build won’t even be registering in their core marketing plans. 
 

However, if the failure rate of units on this forum is representative of all sales then they have an eye watering legacy cost. I suspect they will be doing everything they can to reduce those costs (I.e. not paying!) thus I think @Jeremy Harris has had a great result. 
 

I read a book last week (which I’d highly recommend) called “Supremacy: AI, ChatGPT and the Race That Will Change the World”. I seem to remember it mentioned that using general release of products early and let let Jo public be the testers was now a completely acceptable risk. Anyway making a profit is so last year 😀, it’s all about the exit. 
 

 

[Jeremy Harris]

1 hour ago, Barney12 said:

I read a book last week (which I’d highly recommend) called “Supremacy: AI, ChatGPT and the Race That Will Change the World”. I seem to remember it mentioned that using general release of products early and let let Jo public be the testers was now a completely acceptable risk. Anyway making a profit is so last year 😀, it’s all about the exit. 

 

 

This approach of releasing immature products to the market and allowing the early adopters to test them is now the norm with some cars, too, it seems.  I made the massive mistake of buying a new Tesla Model 3 in 2019, when it was first available here.  That car had so many manufacturing defects, mostly down to process control (or the absence of) and poor software that clearly hadn't been fully tested, that it had to get taken back to the nearest Tesla service centre 6 times during my first few months of ownership.  Given that this was a ~150 mile round trip each time I ended up sick and tired of the thing, so sold it after 14 months (and I'd never buy another one).  Its replacement was a car that had been in production for three years, and it showed.  Zero defects or issues in three years of ownership.

 

The moral of this story is to never, ever, buy a brand new product.  It's not a new thing, either.  There's an old saying in aviation "Never fly the Mk 1 of anything".  It does seem that technology companies, in particular, are far too willing to inconvenience early adopters, though.