scottishjohn

one thing i have learned for sure over 40 years of being in the motortrade running dealerships and something i used to tell all my staff "how do know if the customer is lying ?--his lips are moving "

first ones didnt, have that sort of back up --it makes sense to not tell the driver the REAL battery states as customers will always ignore things unless the onbaord elctronics control what they can do --as you suggest sunamp will be doing the same with the 50% charge limit.

I certainly feel that if sunamp made a statement as to why you cannot do what you want and the technical reason why it would actaully make people much happier and knowing there is technical reason why would then be accepted by most ,especailly fi they said it will shorten the life of the unit Just like the EV cars --everyone now knows ideally you do not keep charging them up to 100% or let them drop below 20% ,cos it will shorten battery life

If it is as you suggest that there are lumps of solid in the liquid ,then that probably why they don,t want it be charged untill it s below this 50% level ,so you don,t end up locally heating the fluid too much and at worst case end up with some liquid close to changing state to a gas with solid lumps which have not managed to absorb the heat from the liquid parts quick enough . and the latent heat could cause that ,as all materials have a latent heat range where you need to put alot of energy in to make them changetemperature + state Ice has a larger volume than water ,then as you cool it even more it shrinks ,now not sure how much of this is to do with "free gases " in the ice ,but if same occurs in this medium ,then theres your reason for bulging cases, and we all know that ice can split pipes + rock . So possibly the cases are just not large enough to accomodate these possible situations of excessive localised heating from an immersion heater + solution is just make more space in the case ? do the first type of sunamp units have same case problems? I am not slagging the unit --just trying to get a handle on how it works and its limitations

stupid question about how thisPCM actually works is it a reversable chemical reaction or purely like water freezing and and melting and if the former how does it decide to stop if its the later then i am guessing it is a latent heat situation and the energy you have taken lowers the temperature of the whole mass and stabalizes the temp once heat has stopped being removed through the whole mass ,or is it lots of seperate cells .like batteries where some are discharged and some still full if you did not have them all directly connected to each other in series

and what issues would they be ?- -seem to have got a pretty good system --simple to erect ,very little bracing needed --a continuos concrete wall --no durisol webs which mean the whole thing needs rendering to make it air tight the panels look far denser than durisol as well ,I tried nailing a couple of durisol blocks together and it just broke bits off and no grip what so ever in the blocks . .sample blocks from durisol no it does look good

ring uk agent and ask them --they will know

a nice copper roof would look well -when it turns green .LOL

personally having built 2 large portal frame buildings with steel cladding +roofing 20years on the sheeting started to peel its plastisol coating - there is no real way to cure it as any paint coating will be on top of the plastisol that has not come off yet--so it will peel later so my money would be to go for the cement board corrosion never enters the picture then

best use of solar thermal I have seen was a house in the swiss alps lots of bright clear days even in winter the tank was built on outside of a blank gable end +insulated with 6" of pir foam ,which was then rendered to look like rest of house and very tall nearly right to peak of very sharp angled roof fire place and chimney right behind the tank --so some free heat from that when it was on in winter ,as it had a back boiler type fire set -up as well the thermal stratification would be great ,as hot water goes to top ,where you would have your output coil. bottom of tank maybe 25ft below you have the solar coil . it just keeps pumping up the temp and over time it fills with heat from top downwards . On this house it ran all heating and hot water requirements dhw coil at top UFH coil above half way ,but not near top solar and back boiler coils at bottom my guess would be well over 15000litres from my close to 20years of running solar thermal maintaince is very small no more than any other system --you only got a pump,a valve and a controller +a couple of thermo couples I used simple analog control system with thermostats to decide when other forms of heating could work ,solar always having priority if the panels were more than 6c hotter than BOTTOM of tank and unless top half of tank was less than 45c ,then boiler came on till top of tank was 50c thats was plenty hot enough for dhw certainly a modern set of sensors and a laptop would make a much better job of controlling it though limiting factor was always size of tank -as i used unregulated tubes -did not turn off till solar manifold was 100c ,which was why I ran it at 3.5bar and big expansion vessel . quite common in summer to find tank temps top and bottom were 97c by lunch time even occasional boiling and venting of steam,like an old steam engine --so maybe a 500 litre min would have been better--we all learn by mistakes. analog pipe thermostats are not the most accurate either I certainly believe you could get dhw nearly all year if thats all you used it for with 500litre tank and blending the output at tank to say 50c If you could get a small cheap heat pump then it definately would be a winner. you can get 20c-30c+ hot water from solar almost everyday of the year just not sure you should need that much heat in a near passiv house to be worth the complications -

I admit to having a thing about solar thermal,having had 2x20tube thermomax evac tube panels on house for 20 years and seeing how much they contributed to underfloor its all about getting a cheap tank sorted my thoughts were to use some sort of icf to make make tank ,and if buidling new house then under it would be fine . are you going for high temp and small volume in sections or just high vol lower temp energy stored will be the same ,upside of ging for largevol at lower temp is panels will wor nearly all day --no stagnation at any time which was problem with my system only 300litre storage so if no underfloor requirement it would max out by lunch time and as you have no control over solar temp better to get it even at lower temp when ever you can

sounds about right normally you use as little as you need to get floor level less you use the better--more space for tiles and it can be a little britle in a thick layer

how about big water storage under house + 1 or 2 solar thermals to warm it up by thermo syphon heat pump to take heat out of it as required--would only need minimum size heat pump as the water will be warm while solar heats it back up as and when it can now if doing it while building house it might be viable I looked into mega size store tank using solar thermal ,but costs for tank were too much --guess 10k in concrete forms etc

basically its like having a pond in the garden you use for the GSHP? I asked planning about doing this 20 years ago ans SEPA said no --cos i would kill the wildlife in the pond

yes ,cos when i rung them to get full info and made a comment about"bean counters" ,they suddenly knew who i was and my view on that still is relevent --if they made the containers thicker they would not cause deformation of cases, I understand it a salt mixture ,so using metal is not an option -but thicker thermo plastic is as is GRP or maybe a fibre re enforced ceramic that could be another heat storeage component so yes they look at it

surely that can,t be right! we keep getting told we need these highly skilled european workers !!!! all it means they are bidable and work cheap ,in both meanings that maybe why most popular way to build in polland is ICF ? time we dumped bricks +mortar for 21st century alternatives-sips+ICF

maybe far too much plasticiser+antifreze or dot +dab with dry mix to lay bricks very quickly and then point with good mix to make it look right --that would speed up the brick layers output in on bonus so looks right ,if they had pointing right but sod all bond

something else going on ,as those pictures show a good coloured mortar mix --15-1 sand to cement wouldn,t be that colour if sand was usual yellow colour ,when i mixed my bedding mix for pavoirs and that was 8-1 it still looked dark yellow so some very fishy about the cement +sand being used-- even looks reasonably glossy like you get if mixing strong for pointing i use quinn cement from jewsons and its bloody strong in right mix -you wont, knock it off the bricks easy

my guess would be he whined enough for someone high up to say "get this off my desk ,shut him up"

great +simple minds think a like

looking for a " work around" an extra thermal store where you run off excess charge insunamp till it hits recharge swithcing point or just run the hot tap a bit ? not a solution --but could be cheaper than having E7 charging it up at night

correct --plenty of length even after you pull them back a little

would be interesting to check and see if they are all crowned a little--so when you load them they go down flat--in theory

all I would say is check the white book on the do,s and don,ts --its all there definately need wood where you fit door frames

just make sure no dips in it that could hold water which could freeze over night