Sunamp container bulging

[willbish]

7 hours ago, Barney12 said:

Plus even something as simple as doubling up means you have significant logistical issues, they take up a large amount of space and have to be on the floor. 

 

The sunamp home page says they are stackable? 

 

I hope this is not another marketing diversion like the advertised A+ ErP rating but in reality comes with a C sticker. (That has annoyed me because I can't see how it is anything other than false advertising and purposely misleading)

 

I was planning to stack my units...

[scottishjohn]

44 minutes ago, willbish said:

 

The sunamp home page says they are stackable? 

 

I hope this is not another marketing diversion like the advertised A+ ErP rating but in reality comes with a C sticker. (That has annoyed me because I can't see how it is anything other than false advertising and purposely misleading)

 

I was planning to stack my units...

that,s to stop the lids bulging .LOL

[scottishjohn]

10 hours ago, JSHarris said:

@oranjeboom,

 

We have a system where in winter our ASHP heats a buffer tank to 40 deg C and water from that is then pumped (on DHW demand, with a flow switch) through a plate heat exchanger to preheat the cold water that feeds the Sunamp.  This means we get a bit of heat into the water, typically it is raised to between 20 and 35 deg C before it is passed to the Sunamp, reducing the amount of energy we need to draw from the Sunamp itself.

 

There's no problem with overcharge, as that can't happen as long as the PCM is kept below its breakdown temperature of ~125 deg C.  The sensors limit the PCM temperature to well below that, no more than about 70 deg C I believe, so it's well within the allowable limit.

 

I'd pretty sure the problem isn't a safety-critical issue, just one of dealing with a challenging sensing and control problem.  I'm not convinced that the behaviour of the Qontroller has been completely and thoroughly modelled as a part of the product testing process, and that the situation of a usage pattern where less than 50% of the capacity is used before a key recharge opportunity seems to have been missed from either the specification of the test process.  It so happens that our usage pattern is exactly this, so the failing, and the consequence (running out of hot water for showers) may well  not have been considered during the design process (my personal view is that it was overlooked, and they concentrated on users who use more than half the capacity all the time).

 

I know that at least one person, other than @Nickfromwales has informed them in writing of the issue, as we aren't the only ones to have discovered the problem.

wee suggestion .

now you have basically sorted the 50% threshold problem .all be it a work around 

maybe some data logging to see if you do indeed continue to put heat in and raise pcm well above the normal cut off point ,do you get more heat loss and therefore not good use of extra excess pv?

fitting more  in cascade mode to always have capacity  will increase capitol cost   

HOW many years  then before it gets to pay back point ..

 

[Barney12]

1 hour ago, willbish said:

 

The sunamp home page says they are stackable? 

 

I hope this is not another marketing diversion like the advertised A+ ErP rating but in reality comes with a C sticker. (That has annoyed me because I can't see how it is anything other than false advertising and purposely misleading)

 

I was planning to stack my units...

 

Well it’s a box so yes they’ll stack in theory BUT and in my opinion it’s a bloody big BUT once you get bigger than the smallest units....

 

As this thread has proven the case design can’t withstand much force, I’m sorry but I just can’t see them being able to support the weight of an additional unit but I suppose the case will withstand downward force better. 

 

But there is a more fundamental problem that you’ll need to overcome......you’ll need some lifting gear probably a genie lift as a minimum, have a look at the table below these things weigh a lot and they are a smooth white box, no lifting handles or lifting points. 

 

Lastly, all the plumbing is in the top of the units, so you’ll need to plumb one at a time. Personally I’d ensure that the bottom unit was working before I bought in the heavy lifting gear to plonk one on top!

 

In summary; I wouldn’t do it. I had originally considered stacking mine but the plan was to get my local steel fabricator to make up a frame for each to stack into. It would have never worked though as I don’t think I would have got the required lifting gear into the plant room. 

 

[Onoff]

Stacking would solve all these bulging lid issues surely?

 

The one above would stop the lower one's lid bulging and you wouldn't see the top ones bulge as it'd be too high!

 

[joe90]

Stacking  may lead to the sides bulging if they are that heavy (ask @JSHarris how heavy they are ?)

[oranjeboom]

"The outer case and hydraulic and electrical connections are designed so that multiple batteries can either be stacked or positioned side by side and then connected either in series or parallel."

 

For the amount of money they cost, it's not worth the risk trying to stack these unless you have a safe method to do so. I think you can arrange the plumbing from the side of the units rather than solely through the top.

 

 

But in the confines of most domestic settings, you wouldn't be able to have sufficient clearance/space to stack with lifting gear etc. But even if you did, I would stack them on shelves rather than on top of each other.

[Barney12]

3 hours ago, oranjeboom said:

. I think you can arrange the plumbing from the side of the units rather than solely through the top

 

The pipework can come out of either side or the back. You simply rotate the tectite elbows. But, it all needs doing from under the top lid. There is no other access. 

[Jeremy Harris]

I've just had a look at the way the Sunamp is performing, with the regular reset procedure every day.  Looks pretty good still, in that it still seems to be utilising close to 100% of the available excess PV generation.  It seems that the time switch reset makes a significant improvement in the ability of the Sunamp to charge from any available excess PV generation, such that I'd now say that the unit is performing perfectly (albeit with a bit of a bodge to get it this state).

 

Interestingly, it now looks as if we are getting around 1/3rd of our DHW energy requirement met by excess PV generation,even during what's been a pretty dull December, with  lower than average PV generation for the month.  This bodes well for us being able to get to zero imported energy for DHW by around the end of February, based on the history of our PV generation system since it was first installed.

 

The next stage is to switch to E7 to reduce the cost of the early morning boost charge in winter, but the saving is modest, as even at peak rate it looks as if we're paying only around 30p to 40p/day for DHW in winter, which still seems pretty reasonable to me.  Switching to E7 would drop this to around 20p to 25p/day for winter DHW at a guess, so only a saving of around £20 a year or so.

[ProDave]

I would be honestly surprised if you can find an E7 tariff that does not "cost" you your modest saving, by the additional standing charge and higher daytime rate.  I watch with interest.

[Jeremy Harris]

14 minutes ago, ProDave said:

I would be honestly surprised if you can find an E7 tariff that does not "cost" you your modest saving, by the additional standing charge and higher daytime rate.  I watch with interest.

 

 

The saving is far from just the DHW, now that I have a fully electric car.  I've had a go at modelling our year around electricity usage and reckon that around 40% to 45% of it could be at the E7 rate, and that does result in a worthwhile overall saving.

 

This is getting to be a bit off topic, though, so I'll start a new thread, referencing this one.

[Ferdinand]

On 18/12/2018 at 09:09, joe90 said:

Stacking  may lead to the sides bulging if they are that heavy (ask @JSHarris how heavy they are ?)

 

Sufficiently light such that one man with climbing equipment, a block and tackle, and oodles of safe lifting experience can do it in under a day and survive intact .

 

What we need is a planning regulation that requires one of those Georgian Warehouse Hooks and a Capstan in every self-built dwelling.

Edited January 1, 2019 by Ferdinand

[Nickfromwales]

Yes, lets please keep this thread concise, thanks.   

[Eileen]

Re your daily reset ploy, JSH, have you managed to get any feedback from Sunamp about this? I would also love to know if anyone can suggest someone from Sunamp who actually responds to technical queries.

 

[newhome]

4 minutes ago, Eileen said:

Re your daily reset ploy, JSH, have you managed to get any feedback from Sunamp about this? I would also love to know if anyone can suggest someone from Sunamp who actually responds to technical queries.

 

 

Tweet them - they seem more likely to respond on there as it's more public than a good old fashioned customer query. And keep on Tweeting them if you don't get what you're after - they want you to DM them instead to prevent it being public I imagine. 

 

[Jeremy Harris]

29 minutes ago, Eileen said:

Re your daily reset ploy, JSH, have you managed to get any feedback from Sunamp about this? I would also love to know if anyone can suggest someone from Sunamp who actually responds to technical queries.

 

 

 

No, no response.  TBH I've sort of given up and to start with I'll just build-in a timer to do the job.  When I get a bit of spare time I'm going to look at making a hot water charging unit, as an add-on, that connects to the lower power heat exchanger.  It should b easy enough to build and test such a unit without having to connect it to the Sunamp, so I can iron out any bugs.  Should be an interesting exercise, getting the control system to work OK.

[Nickfromwales]

2 hours ago, Eileen said:

Re your daily reset ploy, JSH, have you managed to get any feedback from Sunamp about this? I would also love to know if anyone can suggest someone from Sunamp who actually responds to technical queries.

 

Who installed your unit ?

[Triassic]

Can’t wait for the Sunamp office to open tomorrow for an answer to the question about PV charging !

[newhome]

24 minutes ago, Triassic said:

Can’t wait for the Sunamp office to open tomorrow for an answer to the question about PV charging !

 

They’ve given the answer already- “chill man, don’t get hung up on it” ?

[Triassic]

5 hours ago, newhome said:

 

They’ve given the answer already- “chill man, don’t get hung up on it” ?

If that’s the case would anyone like to buy an unused Sunamp and some solar panels, as I’m going back to an oil fired boiler, it’s going to the cheaper than grid electricity

[newhome]

39 minutes ago, Triassic said:

If that’s the case would anyone like to buy an unused Sunamp and some solar panels, as I’m going back to an oil fired boiler, it’s going to the cheaper than grid electricity

 

Will give you a grand for them . 

 

Someone needs to keep on at them on Twitter. I had to stop when they asked me some technical questions that I clearly couldn't answer (ie did I have the @MyEnergiLtd edi, @PowerDiverter or Solic 200) but someone could pick up the mantle surely? What supposedly scientific company can quote figures of 90% and 50% and then say "please don't get hung up on the specific %ages"? Of course people are going to focus on quoted percentages as their heating solution depends on it. There's a heck of a difference between not accepting charge until 50% depleted (as per the manual) and accepting charge when "still nearly full" that they are now claiming is the case. Still nearly full is 90% plus in my view ... 

 

@JSHarris would you say that yours accepted charge when "still nearly full" before you added your switch on and off to the system? 

 

 

 

[Jeremy Harris]

23 minutes ago, newhome said:

 

Will give you a grand for them . 

 

Someone needs to keep on at them on Twitter. I had to stop when they asked me some technical questions that I clearly couldn't answer (ie did I have the @MyEnergiLtd edi, @PowerDiverter or Solic 200) but someone could pick up the mantle surely? What supposedly scientific company can quote figures of 90% and 50% and then say "please don't get hung up on the specific %ages"? Of course people are going to focus on quoted percentages as their heating solution depends on it. There's a heck of a difference between not accepting charge until 50% depleted (as per the manual) and accepting charge when "still nearly full" that they are now claiming is the case. Still nearly full is 90% plus in my view ... 

 

@JSHarris would you say that yours accepted charge when "still nearly full" before you added your switch on and off to the system? 

 

 

 

 

Unless I switch it off and on again to reset it, then 9 times out of ten it won't accept any charge at all after running off two morning showers.  Once or twice it has decided to accept a charge at this point without me resetting it, but that's the exception rather than the rule.

 

The problem then is that we can have a sunny day and yet the Sunamp sits there as a dumb dead weight doing nothing at all (unless I've reset it).  At this time of the year it may, possibly, cool down enough to accept the grid boost charge in the early hours of the next morning, but we've already had one occasion when it didn't, and the second shower ran cold the next morning (which is what got me involved in trying to find out what was going on).

 

Currently, with me resetting the unit every day, it's reliably utilising any excess PV generation we may get.  I can't really fault it, in terms of performance, it's just the failing in the control system that lets it down.  I have a narrow DIN rail mount time switch and plan to wire that into the box to do an automatic reset, just to save me having to go in the services room and turn the thing on and off every day.

 

I should add that this problem only occurs for users whose normal usage pattern discharges a bit less than 50% of the Sunamp's capacity each day.  Those who tend to use more than 50% per day may not have a problem.  For us, I wanted the additional capacity as a buffer, so that excess PV generation from one day could be stored to be used the following day, in case it was cloudy.

[oranjeboom]

On 06/01/2019 at 17:24, newhome said:

"please don't get hung up on the specific %ages"?

 

Did they really say that?? Wow...

 

That's a bit like an F1 car being able to only drive at full speed round the circuit when it's got at least 90% in the fuel tank. "But don't worry  Mr Hamilton, under 90% you can still toodle along at 10mph"....

 

I did see someone's post on this left unanswered on Twitter. Poor show by Sunamp if this is how they continue to provide support.

[Onoff]

11 minutes ago, oranjeboom said:

 

Did they really say that?? Wow...

 

That's a bit like an F1 car being able to only drive at full speed round the circuit when it's got at least 90% in the fuel tank. "But don't worry  Mr Hamilton, under 90% you can still toodle along at 10mph"....

 

I did see someone's post on this left unanswered on Twitter. Poor show by Sunamp if this is how they continue to provide support.

 

Pretty sure they have stated elsewhere that some sort of pv utilisation upgrade / fix is imminent.

 

 

[oranjeboom]

1 minute ago, Onoff said:

 

Pretty sure they have stated elsewhere that some sort of pv utilisation upgrade / fix is imminent.

 

 

have they now? That would be good. Just found it I think:

 

https://twitter.com/SunampLtd/status/1077303328537825281