Sunamp failure - NOW FIXED!

[Nickfromwales]

Just now, Mike said:

If only! I'd need to pay to upgrade the supply for the entire building to get that!

 

The heater would be great solution, but I only have a 45A single phase supply and already need a load-shedder to switch out non-essential loads if the kitchen is in full use...

“Bugger”.

 

Bath?

[Mike]

No bath, just a shower.

[Nickfromwales]

19 minutes ago, Mike said:

No bath, just a shower.

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

 

Or for single phase also, the baby brother of the 27 is..

 

https://www.stiebel-eltron-usa.com/products/tempra-plus-whole-house-electric-tankless-water-heaters

 

 

These don’t need any discharge or G3 etc, just a cable and a cold feed in / hot pipe out.

 

Reviews seem great, and some landlords using them for HMO’s and blocks of flats etc with great results. 

[TerryE]

2 hours ago, Mike said:

The problem is that none of them are as low as the SunAamp, and all (except the Twido) require extra height for pipe connections and/or service space at the bottom - so the installed height is greater and vital wardrobe hanging space would be reduced or eliminated.

 

As you may have gathered from this thread, SunAmp units are far from maintenance free, and so IMO they need decent maintenance access all round, compression turn valves on all in/outs and the ability to slide the unit out in extremis.  We made the mistake of not doing this. They are also extremely heavy.  So my suggestion is that if you do want to "hide" the unit in a "wardrobe" then install it on a platform and make your "wardrobe" open backed and fixed to the wall with bolt fittings so you can unbolt and temporarily remove the wardrobe entirely for easy maintenance access when needed.  

 

Edited Sunday at 14:52 by TerryE

[Onoff]

Sounds like it would be sensible to install Sunamps on a wheeled dolly!

 

 

[Mike]

Yes, that could be an alternative as it would fit at the top of a wardrobe (in France they're often hanging on the bathroom wall looking pig-ugly). The downside is again the encroachment on the wardrobe storage space, which has a SunAmp-sized space reserved at the bottom (to the left of the Willis heaters). It could also go at the top, though that would squeeze the hanging space from top and bottom, and would also need the partition to be reinforced to take the weight.

 

The 'best' fitting tank I've come across that would fit in that space is the Atlantic PC30 model, which stores 30L uses 2kW. Or 50L if I lost some additional height. But that's a lot less hot water than a similarly sized SumAmp ePlus 150.

 

5 hours ago, Nickfromwales said:

Or for single phase also, the baby brother of the 27 is..

Unfortunately the smallest, at 12kW, would trip my 45A supply all by itself. I could no doubt find an alternative that uses less, but with the water main currently delivering water at 7°C, the flow rate would start to get rather limited.

 

UPDATE: Just checked and I can increase the supply from 45A to 52A, so I'll look at that again.

 

I do appreciate the suggestions though! Until I actually place the order (there's still a few months to go) the decision is still open, and I have been revisiting the options from time-to-time. Especially every time someone posts another negative experience here.

  

4 hours ago, TerryE said:

SunAmp units are far from maintenance free, and so IMO they need decent maintenance access all round, compression turn valves on all in/outs and the ability to slide the unit out in extremis.  We made the mistake of not doing this. They are also extremely heavy.  So my suggestion is that if you do want to "hide" the unit in a "wardrobe" then install it on a platform and make your "wardrobe" open backed and fixed to the wall with bolt fittings so you and unbolt and temporarily remove the wardrobe entirely for easy maintenance access when needed. 

Yes, the unit won't be jammed between two walls and there is enough space to accommodate a bit more than the 'servicing space' required by the manual (and more space again if the connecting pipes are removed). A good point about making the wardrobe removable; it will be fitted between partitions so with easily-removed wall-mounted rails & shelving behind doors - probably sliding ones, though that that's yet to be decided.

 

As for manoeuvring it, that is a concern. Provided I risk bringing it through the window on my scaffold hoist, then it will have to slide horizontally for a few metres without damaging the floor tiles. I've been wondering whether a low-friction mat might help or be totally ineffective. Any thoughts?

 

[TerryE]

Janet simply hated them for their flaws, but I was torn: I really liked the concept but there are so many design issues left unaddressed or unoptimised that I am glad that we decided to replace ours.

 

Take the issue of the strict cuboid form factor. Superficially this has lots of installation advantages because you can install the unit in a tight space without much space overhead -- except this is a dangerous assumption unless all of the risks are addressed. 

• For this concept to work you would really need a unit designed for all maintenance access on one side, and this is not the case.
• All components that don't have a life that is significantly greater than that of the overall unit could fail in life and therefore need  to be field-replaceable, e.g. heat sensors, heating elements, etc.
• The fluid design issues can't be ignored but IMO they largely are.  The Sodium acetate trihydrate (SAT) PCM is heavy (S.G ~ 1.45) and cycles through a phase change roughly daily.  The PC expansion coefficient is small but not zero, so the unit must be designed to facilitate this flex, and ditto all connectors and fitted components. A strict cube is a bad choice there. The cylinder is preferred for a reason. The fascinating Youtube History of the Jerrican discusses the evolution / design of a similar cuboid container that has been largely unchanged in 70 years.  The SAs use plastic cells in a bolted steel box for support, but if you remove a side panel for maintenance access (except when the unit is completely cold) then game over.
• Ditto heat transfer.  The unit needs to support ~30kW thermal transfer from the PCM to the potable water and this requires internal cell design especially as this has to happen throughout the phase change cycle. The SAs do better here, but IMO the UniQ implementation is still far from optimum.

I could go on with more detail, but this post has already lost most readers so time to pause.

 

Edited Sunday at 15:55 by TerryE

[Nick Laslett]

So, seriously are they worth putting on wheels?

 

My unit is still to be installed. But it is easy to access and I can even use my sack barrow if I need remove it at some later date. 
 

I have two DeWalt Construction Jacks which can lift 150kg per jack. 
 

https://www.dewalt.com/product/dwht83550/dewalt-toughseries-construction-jack

[SteamyTea]

5 minutes ago, Nick Laslett said:

seriously are they worth putting on wheels?

Will get very high point loads on the floor.

 

[Jeremy Harris]

25 minutes ago, TerryE said:

Janet simply hated them for their flaws, but I was torn: I really liked the concept but there are so many design issues left unaddressed or unoptimised that I am glad that we decided to replace ours.

 

Take the issue of the strict cuboid form factor. Superficially this has lots of installation advantages because you can install the unit in a tight space without much space overhead -- except this is a dangerous assumption unless all of the risks are addressed. 

• For this concept to work you would really need a unit designed for all maintenance access on one side, and this is not the case.
• All components that don't have a life that is significantly greater than that of the overall unit could fail in life and therefore need  to be field-replaceable, e.g. heat sensors, heating elements, etc.
• The fluid design issues can't be ignored but IMO they largely are.  The Sodium acetate trihydrate (SAT) PCM is heavy (S.G ~ 1.45) and cycles through a phase change roughly daily.  The PC expansion coefficient is small but not zero, so the unit must be designed to facilitate this flex, and ditto all connectors and fitted components. A strict cube is a bad choice there. The cylinder is preferred for a reason. The fascinating Youtube History of the Jerrican discusses the evolution / design of a similar cuboid container that has been largely unchanged in 70 years.  The SAs use plastic cells in a bolted steel box for support, but if you remove a side panel for maintenance access (except when the unit is completely cold) then game over.
• Ditto heat transfer.  The unit needs to support ~30kW thermal transfer from the PCM to the potable water and this requires internal cell design especially as this has to happen throughout the phase change cycle. The SAs do better here, but IMO the UniQ implementation is still far from optimum.

I could go on with more detail, but this post has already lost most readers so time to pause.

 

 

 

They have changed a lot, @TerryE.  Ours has the two pipes and two cables going in near the top of one side.  There is no need to access the other three sides. 

There are no removable side panels any more, the case just has a removable lid, under which are the electrical and pipe connections. 

You only need access to the top and the upper part of one of the three sides that can be used to bring the pipes and cables out now.   The pipes need enough space on the side chosen to connect them to allow an elbow to be fitted to take the pipes, so perhaps a 100mm wide gap at that side.

The pipes and cables can can come out near the top on either of the long sides or one of the short sides, and no tools are needed to change this orientation internally.

 

[Jeremy Harris]

3 hours ago, Mike said:

Yes, height is certainly important on my current (apartment) renovation, as there is nowhere to hide the unit except a wardrobe. The SunAmp, with its side pipe connections, is perfect for that as there's still space above to hang clothes.

 

Before deciding on SunAmp (not that it's purchased yet) I spent a long time looking for compact alternatives, and also came across some modular cylinders: the Teccontrol Twido, Viessman CEI (perhaps a rebranded Twido, but now seemingly discontinued) and the Ariston Velis Evo; if you've found another, I'd be interested. I've also taken a look at various flat single-tank units.

 

The problem is that none of them are as low as the SunAamp, and all (except the Twido) require extra height for pipe connections and/or service space at the bottom - so the installed height is greater and vital wardrobe hanging space would be reduced or eliminated.

 

 

The other slimline twin tank unit I've found is this one:  https://www.modernheat.co.uk/product/tesy-bellislimo-80-intelligent-electric-hot-water/

 

[Nickfromwales]

3 hours ago, Nick Laslett said:

But it is easy to access and I can even use my sack barrow if I need remove it at some later date. 

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  

 

4 hours ago, Mike said:

It could also go at the top, though that would squeeze the hanging space from top and bottom, and would also need the partition to be reinforced to take the weight.

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?

[Mike]

10 minutes ago, Nickfromwales said:

4 hours ago, Mike said:

It could also go at the top, though that would squeeze the hanging space from top and bottom, and would also need the partition to be reinforced to take the weight.

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?

Sorry - I was referring to the Telford Tempest suggested by Nickfromwales; I should have obviously quoted that in my reply to avoid confusion. No, I wouldn't want to suspend a SunAmp!

 

 

[Mike]

3 hours ago, Jeremy Harris said:

The other slimline twin tank unit I've found is this one:  https://www.modernheat.co.uk/product/tesy-bellislimo-80-intelligent-electric-hot-water/

Thanks! I've added it to my collection. At 704mm high the 40L version - confusingly named the 50 - is interesting, but the manual requires a minimum of 500mm space below (and 50mm elsewhere), which is disappointing.

 

The Ariston may require less (they don't mention it in their information), presumably determined by the length of the sacrificial anodes rather than the tundish as the discharge pipe connects to the top. Although I'd hope that my planned phosphate dosing water treatment device would avoid them having to be replaced in practice.

[Jeremy Harris]

1 hour ago, Nickfromwales said:

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?

 

 

I lifted our original unit upstairs, on my own, with a sack trolley, loads of spare climbing ropes, two Petzl stops as safety brakes, a steel cable and a tirfor winch.  Took me about half a day to get it up a single, straight, flight of stairs.  I used the tirfor with a 2:1 tackle to move it up one step, then locked it off with the ropes and Petzl stops, re-jigged the steel wire and tirfor so I had enough movement to get it up another step.  The sack truck was rated to carry 150kg, but really struggled and has never been the same since.

 

They only way to move these things safely is with something like the guys used on Thursday, a Zonzini powered lift and stair climber.  That had the advantage of being like a mini-fork lift, in that the forks can be motored up from floor level to around the level of the back of a van, and then a couple of people can just about slide the unit across and strap it to the Zonzini.

 

They are, without a shadow of doubt, a manual handling nightmare if you're on your own.

[Mike]

23 minutes ago, Jeremy Harris said:

I lifted our original unit upstairs, on my own, with a sack trolley, loads of spare climbing ropes, two Petzl stops as safety brakes, a steel cable and a tirfor winch.

That's impressive!

 

24 minutes ago, Jeremy Harris said:

a Zonzini powered lift and stair climber.  That had the advantage of being like a mini-fork lift, in that the forks can be motored up from floor level to around the level of the back of a van, and then a couple of people can just about slide the unit across and strap it to the Zonzini.

A very good point - a single start-to-finish solution would be much easier than the multiple moves that would be required to get it from van/pallet -> street -> corridor -> courtyard -> hoist -> floor -> final position. As long as a Zonzini can cope with semi-spiral staircases as well as straight flights, and provided the battery will hold out to the 6th floor.

[Nickfromwales]

4 hours ago, Mike said:

Sorry - I was referring to the Telford Tempest suggested by Nickfromwales; I should have obviously quoted that in my reply to avoid confusion. No, I wouldn't want to suspend a SunAmp!

 

 

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

[Nickfromwales]

2 hours ago, Mike said:

That's impressive!

 

A very good point - a single start-to-finish solution would be much easier than the multiple moves that would be required to get it from van/pallet -> street -> corridor -> courtyard -> hoist -> floor -> final position. As long as a Zonzini can cope with semi-spiral staircases as well as straight flights, and provided the battery will hold out to the 6th floor.

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.

[Gone West]

11 hours ago, Mike said:

The Ariston may require less (they don't mention it in their information), presumably determined by the length of the sacrificial anodes rather than the tundish as the discharge pipe connects to the top. Although I'd hope that my planned phosphate dosing water treatment device would avoid them having to be replaced in practice.

AFAIK the phosphate treatment will not have any effect on the anode eroding. The anodes are to stop the tank material from corroding where there is some possible damage to the interior lining of the tank.

[JohnMo]

16 minutes ago, Gone West said:

AFAIK the phosphate treatment will not have any effect on the anode eroding. The anodes are to stop the tank material from corroding where there is some possible damage to the interior lining of the tank.

The trouble with a lined tank, is any area where the lining is flawed or has a defect (crack, pin hole etc), the base material of the cylinder is subject to huge galvanic corrosion rates. That is the principle reason for the anode and why they have to be replaced periodically.

 

I would not have a lined cylinder to save a few pounds, copper or a decent stainless steel, would be the only choice.

[Jeremy Harris]

12 hours ago, Mike said:

That's impressive!

 

A very good point - a single start-to-finish solution would be much easier than the multiple moves that would be required to get it from van/pallet -> street -> corridor -> courtyard -> hoist -> floor -> final position. As long as a Zonzini can cope with semi-spiral staircases as well as straight flights, and provided the battery will hold out to the 6th floor.

 

 

The stair climber model that the Zonzini crew used here would cope with anything you could get a sack truck up, I think.  It would probably be OK with gentle turns in a staircase but I doubt it would work on a tight spiral staircase.  There are a few videos around on YouTube showing these things in action, they might give you a better clue as to whether or not one would work on your staircase:  https://www.youtube.com/@ZonziniSrl/videos

 

Our local hire place has them, but they are costly to hire, when I looked it was around £230/day, including delivery and collection.  Worth it, given there is no alternative, but I was seriously looking at just buying a secondhand one.  Might be a useful thing to have, or I could probably sell it on for about the same as I paid for it.  They are around £800 to £900 to buy secondhand.

[Jeremy Harris]

I can't make up my mind what to get to provide us with an emergency back up hot water supply.  Space is really tight in the only area I could fit something.  Below are rough scale sketches of the elevation and plan view of this area, with the only spare space marked in red.  The best bet seems to be to find a horizontal water heater that I can wall mount, above the door.  There is "just" room to get up to a 500mm diameter  unit up there, no longer than 1200mm, and it must have all the connections at the end nearest the end wall (top in the plan view).  The pipe work for the Sunamp is directly below that end, so plumbing will be straightforward, plus I can run a drain from the tundish out through the wall to near-ground level, as there is just gravel in that area outside.  There's room for the expansion vessel in the corner where the pipes would come down, too.

 

The unit that seems to best fit the bill is one of the Heatrae Sadlia Hotflo multipoints.  The 50 litre would be a lot easier to fit, as it is slimmer and lighter than the 80 litre (sticks out 371mm from the wall versus 454mm)  Both would be OK within the 1200mm max length restriction.  The fitting bracket these use looks ideal, too, as you just bolt it to the wall and then lift the unit up and hook it into place.  The question is whether 50 litres of hot water is OK as an emergency supply.  My feeling is that it would do at a pinch, as the sums show that it could deliver at least 70 litres of shower temperature water, so enough for about 7 minutes of shower time.  The full re-heat time is a bit over 40 minutes, so just spacing our two morning showers out a bit more would allow a couple of reasonable showers.

 

The temptation is to get a larger unit, just in case, but I have to keep telling myself that this is just a standby system, to give us a backup source of hot water for emergencies, not our primary source of hot water.  I've sketched in the smaller of the two Heatrae Sadia heaters below, and it looks like it would be a reasonable fit.  I've not been able to find anything comparable, in terms of diameter, everything else just looks a bit too large.

 

 

[Kelvin]

The other day my wife asked what we’d do for showers if our system stopped working for some reason. I pointed to the newly plumbed in dog bath and electric shower. Has a handy shelf for sitting on and a door and step to get in. 😂 

[ToughButterCup]

2 minutes ago, Kelvin said:

The other day my wife asked what we’d do for showers if our system stopped working for some reason. I pointed to the newly plumbed in dog bath and electric shower.

 

Has yours been talking to mine then?  Our dog bath is the canal though. My days of cold-water swimming are over

[Kelvin]

2 minutes ago, ToughButterCup said:

 

Has yours been talking to mine then?  Our dog bath is the canal though. My days of cold-water swimming are over

My wife is a keen cold water swimmer and only wears a bathing costume all year round. The Loch waters are very cold. My theory is it’s the reason the sea water temperature is rising, all the women of a certain age going for a dook.