scottishjohn

was hardly a normal summer last year

I have to say i think who ever specified the tank got it wrong -total litreage --not a problem but all in one tank --that limits you to when your sloar can work and will shorten the numberr of hours it can wok if it has to be above main tank temp 3 smaller tanks with different target temps and it would work much better

so what would you say your average air temp is form april to oct certainly up here there are not that many days in normal year where the air is 23-24c or more for that period kitchen is not a good example as you make heat in there when cooking . Is this a thing that is prevalent in open plan houses ?

that might work ,but you going to need a control circuit that makes your pV take primary role for DHW --or your boiler will heat it up and you won,t get full use of PV If i was doing this then I would have boiler primarly doing UFH and only when dhw tank is above 60c? would i divert it to UFH - maybe a separate loop in bottom half of tank for that and divertor valve and pump so you taking water at or below40c for ufh ? then maybe a coil for boiler to top up tank if top half way temp drops below a target temp - so 3 coils in tank ? DHW out uUFH out boiler in then your 2 pv heaters lot of control system needed could be complicated to get best out of PV- sure someone will have a solution

as its a conversion of a building maybe you could do something very novel for over heating like open a window !!. you say its on a budget so maybe you not going with mega floor to ceiling windows anyway --they are expensive and thats where you mega solar gain will come from getting house insulated and air tight should be primary concern i think concern on over heating would not be high on my list on a budget build fabric first-- It would help if you stated a rough budget + floor area of building --then people may direct you on best way to spend it

Hmmm. maybe an opening for making grp frames to fit velux windows to corrugated roofs I made something like this when i built my workshop as i wanted to fit a 30"extraction+ input ducts through the roof take a new sheet use it as a mould to make the base corrugated then you can build up a wood frame to fasten the velux too then use layers of grp to cover the wood frame to bond it to the base section and you have a purpose made cassette to fit to your roof profile . i suggest 3 or 4 layers and coated with grp roof gel cost --then its UV proof,you can get dyes to make it colour you want easy to fit to roof and seal you can offset the velux frame to corrugations as you want to make it look right might seem to be a long way for a short cut but will be perfect fit

no it is not as it was used in comparsion to a gshp where the cop does not suffer in very cold temps i have already said ashp is best choice for uk UNLESS you have a lake where yo can simply throw a big coil of pipe in --eg no costs for laying pipes and remaking ground or drilling bore holes then and only them is a GSHP worth considering

no you have to make this statement at the beginning of the purchase process in writing and if there is an order from write it on it as a condition of sale then it will be considered as a valid reason for cancelling if they do not keep to delivery schedule. too late to try to enforce after you have made the deal with no such caveat in original order process . they can walk away cos they have included that as part of the terms of sale --so you put your own ones on --all part of contract law

its called a diesel generator -with auotstart up

maybe this should be a word of caution to all and to send the supplier a letter which states that if delivery more than 4 weeks late it will viewed as a breach of contract and you require a full refund . they will be the ones stating the delivery time not you and it is not unreasonable for them to get it right within 4weeks of due date If they have a problem with that then change you choice of blocks it is up to them to give you a realistic delivery time when they want some money . if they want up front payment there is no trust involved in the deal --,so it should be a simple contract issue quite sure they are some legal eagles out there who have seen such supply contracts in the past

gshp will give same cop all year round --even in really cold weather,ASHP could be done to near 1-1 in very cold weather --that's the difference and some will also support that they give better COP than ashp all the time but without a lake to dump your coil in --never going to be better than ASHP in uk climate. 10 k difference between air +ground -- will be more than that in some cases -if ithas to be bore hole and not trenches I was quoted 13k just to drill the bore hole +no warranty that i wouldn,t need another one -but if done when drill rig was still there it would save 3k all depends on the ground you have

and what were the temps on the solar thermal on those days ? do you have that info? WSW may work ok for pv --but thermal tubes definately need to be closer to south if possible flat plate may work ok when not direct to the sun ,but again they are no where near as good in our latitude as evac tubes if both were facing right way ,yes you can swivel the tubes in the frame to get better direction ,but only so much or they will be shading each other you say you have 120 tubes --what size storage tank? cos I could boil my 300 litre tank with 40 tubes quite often in summer if i wanted to and that was with a morning tank temp at bottom --using it for ufh --of 20c and top tank temp of 30c. and getting a decent temp drop on return to panels

to get best from solar thermal you will need more than one tank ,if you are wanting more than just DHW with different temp levels for the tanks -so you can always store the heat you are getting eg if main tank has a target of 80c -then days when you not getting 80c -it goes nowhere , so you need to have dif target temp levels for the tanks also if using for ufh a way to send it directly to the floor in winter when temps from panels will be low and your tank temps have depleted I am working on this for my new house ,but price of tanks is always going to be the killer when doing a cost comparison to a ASHP but I think you will be talking about 2 or 3 tanks with a total of 8-10,000 litres,(could be too much with near passiv house, maybe 5000 litre ), I think to get get all year round supply and 3 or 4 x30 tube panels I could be wrong --more work needed yet I would like to do it that way --but doubt costs will stack up by the time you have built concrete tanks in the foundations /plant room

my old petrol station flat roof self seeded sedum on its own -must be lots of seeds in the wind it took about 15 years though to get a good covering

yep -feel your roof on an overcast day --still gets warm maybe if more questions -you should start another thread before we get in bother

no problemo

nothing but copper in solar thermal and compression fittings simple extra temp switch which by pass the controller for emergency sorts that if copper then stagnation is not a problem -my problem was i was continuing to circulate --so foam insulation melted and dripped off the piping and thats 170-180c to do that power cut would not be a problem cos anount of water that would be hot would son drop intemp before it got to sunamp --very little volume in panel

as said above cost of GSHP is far too high in Uk we do not get the very low temps like canada where an ASHP would not work due to being -20 for long periods only time i would consider a GSHP is if i had a lake i could throw a big loop in --then the costs for installation change dramatically and make it the right choice

thats part of your solar controllers job you set max tank temp and also max panel temp --the temp of water leaving the panel . it turns off if too high or you can divert to to a heat dump -like an old radiator somewhere --I like that system better as you do not get high stagnation temps in the panel which will damage panel over time if a regular occurrence. It is unlikely if you have matched panel size with storage tank-- that was my mistake on old system 300litre tank and 2x20 evac tubes--good day you got boiling tank by lunch time even though it the same tank had an UFH coil in it add to that the system was supplied with a PLASTIC air separator --which when temp sensor went faulty some years on it melted then panel temp got that high that it melted foam insulation from the copper pipes . partially my fault trying to get max from it so did not have high temp cut offs set ,but who would spec a solar thermal with anything plastic in it !! but it shows how much heat you can get if tank is not big enough for panels you have one 20-30 evac tube panel is plenty for a 300 litre dhw tank better to have too much and dump it ,than be struggling on a winters day for heat

I know of no car maker that warranties the EV components for 200k 6years or 60 k is most i have seen --that whilst not saying how long they will last tells you how long the maker expects them to be definately trouble free and last time i asked a new battery pack for one car was 6k--thats a shit load of fuel -and all test i have seen say fast charging shortens battery life- I will hold my judgement on Ev cars for sometime yet

His numerous explanations of the system and how it is not doing what the first units did has convinced me , and that@s not easy !! He has not convinced meto go PV +sunamp though .LOL ,that there is a problem with later units and needs to be addressed is obvious and he seems to have used sound experimentation to find this out as to how good the units are in reality in either old or new form could be open to a biased opinion of those that have spent the cash ,but the problem I believe is real If I want to heat from the sun ,then I will be staying with solar thermal for that ,as i have done for last 20 years

Jeremy is spot on with his views on this unit and I applaud him for being so dogged chasing them about the problems we are being told continually to save energy and be more efficient with its usage the ability to use ALL of the excess PV is an imperative towards this goal , especially as now there is no FIT tarfiff worth having to make people go down the PV way 5 -7 years to pay back was one thing now it is much longer ,then some people are just not going to take it up .

bahco are good make

yes the ratchet on cheap tools is always crap if you lean on it best value for money i think is bergen tools --not expensive but good quality + can be used daily -plenty of internet sellers at good prices as well

If i was asked to suggest cheap set for all round use then you want one that goes from 8mm -to 22m 3/8 drive only that will cover most things add to that a set of comb spanners that cover same range and you got a good start I bought some of these a while ago - www.ebay.co.uk/itm/Metric-extra-long-ratchet-spanner-double-ended-8mm-19mm-socket-adapters-AT540/123024120058?_trkparms=aid%3D333200%26algo%3DCOMP.MBE%26ao%3D1%26asc%3D56580%26meid%3D5960d59333af403dbf09b610ad5d2bf9%26pid%3D100008%26rk%3D1%26rkt%3D12%26sd%3D141594486824%26itm%3D123024120058&_trksid=p2047675.c100008.m2219 -i call them my old mans spanners --very long so you can get a good swing without being very strong- you use ring end to crack the bolt then swop ends feeling my age sometimes with some jobs --they have 15mm +18mm which are getting very common --a lot of sets miss these out -