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HAHA! It only bloody works!
73 solder joints, 17 compression fittings and just one leak, in one of the easier places to fix, at the tank connector! Miraculously no leaks outside with my first godawful soldering.
[i]feed from bottom of thermal store coil, through check valve (hot run) and drain cock and pump (bottom run), then round the back of the boiler[/i]
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[i]Copper filler loop and header expansion pipe up to the header tank (flexy one is the boiler filler loop) and past the two bleeders to the DN20 hose outside[/i]
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[i]Header tank with leaky connector. Expansion pipe goes over the top and drops back in.[/i]
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Wired the pump to the mains to run it around.
There's about 27 litres in the system below the tank. A fair bit.
Now to partially drain, fix that leak, then load with glycol mix. Then I can wire up the controller and temperature units that arrived in the post this morning.
Good effort. 1 leaky connection out of all that lot is pretty good going. Keep us up to date with how it works.
I like the more adventurous DIY threads.
Flax and plumbers putty for tank joints.
I had a think about your system when out on the bike this morning and I reckon you weak point is that the system runs at such a high temperature. In Decemeber you'll have trouble getting the primary solar circuit up to the temperature of the thermal store let alone above it. Even vacuum pipes struggle to reach 65°C in winter especially with the losses you'll have on the long pipe runs. The sun comes out, it takes ages to get the panels up to temperature. Once they are up to temperature the pump starts but stops as soon as the cold water in the supply/return circuit reaches the sensor. In the time it takes for the panels to reach 65°C again the water in the pipe runs has cooled down. After a cold night in December it's midday (11:00 am UK) before my solar panel starts circulating with a tank at less than 20°C.
Question answer: When the water from the solar water heater isn't hot enough for a shower I feed into a conventional 50l tank with an immersion heater. A guestimate is that the immersion heater accounts for about 350kWh of our yearly electricity consumption.
In Decemeber you'll have trouble getting the primary solar circuit up to the temperature of the thermal store let alone above it.
stratification my dear Watson!
The thermal store can be 85 at the top and can still be c.20deg at the bottom.
In winter the solar panels are there to "pre heat" the lower temp water when sufficient insolation is available (I can of course change the hysteresis of the controller for winter behaviour if I want), through natural straification, the energy can rise to the top of the thermal store (2m above) at which point the DHW coil is going through the store.
flax etc. nah. Silcon bodging!
I may have missed this but is your boiler happy with a pre-heated supply of water or are you running a separated system?
ck - think of it a bit like this, but rather than the water in the tank going straight to taps there is another coil near the top that indirectly heats DHW.
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hang on, Ill make a diagram that's more relevant...
Hmm boiler to hot water store, not keen on that idea with modern combis but it would make sense with other methods.
modern combis
Oh. Youve missed quite a bit then 😉
here you go. Just knocked this up. Doesnt show all the detail but just how sources and uses of energy are laid out relative to each other.
One of the important bits is the set of opposing pumps between the boiler tank and thermal store which manage energy between the two.
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wun 'undred.....kWh!
Damn and blast...
Everything was going swimmingly, but it seems the s/h pump from eBay keeps binding. Have had it off and open for a clean, but it's got bound again. Must be some gunk inside the motor body.
Temperature sensors all sited and wired up. Controller mounted to the wall and connected to the pump, sensors and an isolating switch. All working fine except the pump. Will strip one more time and see if I can clean it again. If it binds again I may have to get a new one instead 🙁
[i]Controller in middle, isolator above. Pump bottom right.[/i]
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Working the day job tomorrow so a bit of a break. Then wednesday I finally install the evacuated tubes and start producing hot water!
Then wednesday I finally install the evacuated tubes and start producing hot water!
...so that'll be why the weather is turning into a cloudy rainfest then!
I have decided house heating is impossible due to my current setup but I might use it as a thermal store for my greenhouse instead, keep it warm in the cold nights.
For a greenhouse set up, you could do a cracking salvage DIY job with some black painted radiators and an old hot water cyclinder.
In theory it ought to thermosyphon during the day one way, then come back again at night time! 😉
Just need one of those indirect coils that fits in the immersiion heater hole.
cheesey - was thinking just the same thing this morning listening to the weather forecast 🙁 at least its sunny and tits-oot-tastic in That London today still!
sunny and tits-oot-tastic in That London
Oh yes, it's lovely in London today!
Special thanks to the girl on the bike yesterday morning in the almost transparent linen trousers riding towards Holborn Circus. You could even make out the pattern in the lace of her undercrackers! It was a shame I 'couldn't' overtake for a bit 😈
I've managed to rescue a pair of full height freezer condensers and a pair of double glazed window panes to match 🙂 Just need the tank.
you need to make something like this for it:
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Got loads of 10mm microbore spare just waiting for the job 🙂
I was wondering, wouldnt you need one at the top for night time and one at the bottom for daytime?
Original plan was to simply circulate the hot air down to a stone heat absorption tank buried under the floor (insulated box with stones in it, I've about 1m^3 of river pebbles going spare!) with a small 2W fan and leave the fan running day and night to keep pushing warm air out the bottom overnight, but I'm starting to consider a separate water (better) system that simply heats a tank and a tiny pumped water system that pumps the same heated water overnight around under-floor pipework, but I think the majority of that would get conducted away without expensive insulated flooring etc.
The first has the benefit of cooling the greenhouse during the day too
for cheap pumps I [s]recommend[/s] [i]suggest trying[/i]* the 12v ones that are sold at solar project that I linked to earlier.
They're good VFM, reliable and you can run them off an old car battery and solar panel...
he also does fairly cheap hose for them too.
Apprently he sells 1500 of those pumps a year - not just to solar projects but things like motor racing mechanics, fish collectors etc.
* I dont have direct experience but handled one in the shop. Reassuringly heavy and nicely put together. Simple, but compact.
EDIT: CK I may have some spare UFH tubing lying around in the garage if you're interested.
You thought you could hide....
His dullness returns.
Reflectors fitted to the frames. These just catch that little bit extra insolation that goes past the sides of the tubes and bounces it back at them.
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60 tubes ready to be installed. Apparently best not to leave them open to the sun as you fit them as they can get very hot at the copper end after about 5 minutes.
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Pump taken off again, opened up and flushed. Hopefully will run OK. Controller on and programmed to work at dT+6degrees and off at dT+3degs.
Probably start raining again when it's all done....
stoner - IIRC I have a central heating pump you could have for postage.
Thanks TJ. will bear in mind If this one starts giving anymore gyp.
first 20 tubes in. Manifold temp started at 16deg this morning. Now at 33deg and climbing by 0.1deg every 4 seconds under intermittent sunshine and cloudy skies.
time for breakfast.
Surely this is the answer to your pumping woes!
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Unfortunately for a PV array to power a 40W ish 240v pump for 10 hrs a day, Id need something like a 200W array which would be about £600 plus £100 for a 100AH battery and £50 for an inverter....
And that probably would still suffer in winter.
But your thinking's nearly sound cheesey! 😉
Update? More pics?
sorry for the delay there sunshine fans....
Events. Events.
Anyway...thermal paste on the business end:
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20 in.
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60 in
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Finished installing the tubes by 13:30 this lunchtime, and I think promptly boiled the water, but had to rush out so set the fan speed to pos 3 (fast) to make sure it didnt do anything silly. Just got back and everything seems OK.
Have adjusted the call for heat trigger temp for the boiler so that it fires at 55deg, not 65deg and shuts off at 75deg not 85deg. I want to keep a decent wodge of cooler water at the bottom of the thermal store to make the most of the array energy.
Its going to take a bit of time to get the temp settings bang on, as well as the pump speed setting, Im not sure that pos 1 isnt too slow in mid summer...we'll see.
I think I will replace one of the manual bleed vents with an auto one OR re-route the expansion overflow so that it comes from the return bleed vent tail because when it was stagnating there was quite a bit of knocking and I think it's because of the route the pipes take when they come into the building. Not a trained plumber so some trail and error to expected...
Top work!
No, those lines in your grass need investigating. I suggest that we all come round and do a STW syle 'Time Team' investigation.
Good work Sir 🙂
I thought I had a decent size garden, but yours takes the biscuit 🙂
Make a great set of goals.
cheesey - you so much as think about stabbing a spade in my lovely new lawn and you sir will be 3 feet under my terrace!
Unfortunately you wont find anything down there except gravel. I put 100m of land drain in because we're on solid clay and the trade off for not having a boggy quagmire ofr 6 months of the year is that the areas directly above the soakaways stresses the grass a little bit harder in hot weather.
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and this is the land drain outfall
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Quick check of the numbers:
Steel hose and fittings £285
Pump and gate valves £29
Solar controller £71
Heat transfer fluid £34
Copper work £150
3 x 20 tube panels £1,440
Total £2,009
Trench, conduit and hose = 12hrs
Copper work in the boiler room = 16hrs
Build and site frames = 4hrs
Install tubes = 4hrs
*quietly puts spade and trowel back in shed and shuffles off looking innocent*
Quick check of the numbers:Trench, conduit and hose = 12hrs
Copper work in the boiler room = 16hrs
Build and site frames = 4hrs
Install tubes = 4hrs
So how much is your hourly rate? How much did those 36 hours cost you?
Stoner - you have a 'haha', now that's posh.
Have you got grey water tanks installed for the flushing and washing machine too?
Bunnyhop - My original plan was to have rainwater harvesting. I have plumbed the barn with a secondary service for the dishwasher, washing machine, master bathroom WC and downstairs WC (but not guest - intermittent flushing = stagnant water).
However the cost of the storage tank and pumping station was about £2.5k. The water savings would only have been around £50 pa at most, so it made just no sense at all. If it does at a later date, then the house is ready for it and I can install it then.
Not a haha. A ditch, love.
my only pic with a bit of the fencing on top of it too.
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Matthew - at my hourly rate I made a HUGE loss 😉 But im actually in between projects so its nice to do something I want to do with my time instead...
at my hourly rate I made a HUGE loss
I figured it was a labour of love. Paying someone to do the work would be missing the point.
The whole project is really impressive. A bit like Grand Designs except there have been no major cock ups and Kevin McCloud isn't wandering around.
On time, on budget. Of no interest to Kevin 🙂
I dare say I'm not the only one who's a bit jealous of Stoner now
#waits for Stoner to realise that he's producing enough hot water for all his current domestic hot water needs and that everything apart from the circulator pump on the panel circuit can be switched off# 8)
Stoner - MemberOn time, on budget. Of no interest to Kevin
Fair point. There always seems to be a pregnant woman hanging around in Kevin's show as well. I don't see one in your pics.
Edukator - Member#waits for Stoner to realise that he's producing enough hot water for all his [s]current[/s] [b]neighbours' [/b]domestic hot water needs and [b]starts supplying them.[/b]
FTFY
S'good that, innit? I mean, I don't understand any of it, what with being an idiot and that, but it's very impressive. Good to see folk trying out ways to save energy and stuff, but I can't help thinking it requires so much extra paraphernalia, which needs to be manufactured and uses up other resources and energy. Then there's the extra time spent installing it all.
Is the idea of 'sustainable living' simply little more than an illusion?
Elfin, you can generally use "cost" as a proxy for "embedded energy". This looks like it's got a short pay back so I'd expect it to save energy overall.
Forgive my scepticism, but I see a lot of projects of this nature around, but they invariably seem to require loads more extra equipment/materials/space etc. I'm totally behind any project that will genuinely help save on precious resources, but they very often seem to come at a pretty high cost, not least in terms of money, and don't always seem to offer quite the rewards promised.
I am impressed to see some canal boat dwellers utilising solar panels, but don't the panels themselves involve environmentally destructive processes in their manufacture?
Seems to be a fair amount of Robbing Peter To Pay Paul with 'green solutions'.
When surely the answer would be to just work out how to use less energy, not find other ways to produce the same amount?
In energy and resources terms these things pay for themselves very quickly.
Insulation materials repay the energy needed to make and transport them within a year. Things made from biomass are a carbon sink and have no CO2 payback time in that the CO2 produced in production and transport is equivalent to the carbon they contain.
PV panels pay for themselves in energy terms in a year or two depending on where you live, and solar thermal is of the same order. Copper, aluminium, glass and steel are very easily recycled.
The next time you think of replacing a central heating boiler, immersion heater or anything that uses energy sit down and work out how much more the sustainable option will cost and how long it wil take to pay for itself in energy saved (or in terms of cheaper fuel used in the case of wood). You may find the eco option is cheaper as well as being sustainable.
Stoner's system is the high-tech solution. My own is the low-tech one relying on thermosyphon for the water heater and me throwing logs on to heat the house (which doesn't require much heating because it's so well insulated). There's a solution for every home if you look.