Green Building Forum - DIY Solar project connection help Thu, 16 Apr 2026 18:00:50 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142439#Comment_142439 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142439#Comment_142439 Thu, 12 Apr 2012 22:20:14 +0100 budbecks
Ok i have a old rad and can make a box similar to the one described here

http://www.diydata.com/projects/solarpanel/solar_collector.php

All i want to be able to do is heat 1 rad from the "solar collector". Both rads are about the same size, if anything the rad indoors is slightly larger.

The "solar collector" is outside about 7 meters away from the internal rad. All the pipes will be super insulated using 32mm wall 15mm armaflex. It can be pumped using a heat stat and pump or failing that just gravity.

Could anybody show me the simplist way to plumb this in ?

Could i literally connect each rad up, the solar being lower to allow to rise ? possibly adding a vent to the rad ?

Any help would be great]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142441#Comment_142441 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142441#Comment_142441 Thu, 12 Apr 2012 22:30:31 +0100 SteamyTea
So the hottest point needs to be the lowest.
You can vent at the highest point to allow for expansion or vapour release.

If it is pumped then just make sure that water is always pumped uphill, so pump at lowest point, then from the bottom of a radiator to the top, up the insulated pipe to the bottom of the next radiator, out the top and back to the pump. Vents at the top again and make sure that the vent pipe has liquid in it to stop air being drawn in.

I would think]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142444#Comment_142444 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142444#Comment_142444 Thu, 12 Apr 2012 22:58:10 +0100 Peter_in_Hungary but would add that I would not pump it - gravity is simpler and is self regulating. If you put in a pump then controls are needed to stop cooling the inside when there is no heat outside. Gravity will stop as soon as the lower rad is cooler than the upper rad and the hotter the lower rad is, relative to the upper rad, the faster the circulation will go. I would also put antifreeze in the system.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142448#Comment_142448 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142448#Comment_142448 Fri, 13 Apr 2012 00:05:20 +0100 tony DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142460#Comment_142460 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142460#Comment_142460 Fri, 13 Apr 2012 08:05:13 +0100 budbecks
I cannot install an F+E tank very easily, although it is possible, would prefer to try and do without it.

Yes the rad outside lower, about 1.5 - 2 metres lower.

If i was to use a towel rad as the "emitter", could i just take 1 or 2 of the plugs out of the top to act as the so called "vent". fill it with slightly less water to allow for a little exspansion ? or use a auto-vent rad plug ?

Thanks again]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142462#Comment_142462 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142462#Comment_142462 Fri, 13 Apr 2012 08:27:54 +0100 SteamyTea To transfer more heat (the word heat is just energy) you need large bore pipes as it it is the mass moved by the temperature difference.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142470#Comment_142470 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142470#Comment_142470 Fri, 13 Apr 2012 08:54:54 +0100 tony
have a go and try it, use as few elbows as possible in the pipes, ideally none and I would use plastic pipe.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142505#Comment_142505 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142505#Comment_142505 Fri, 13 Apr 2012 12:06:38 +0100 Ed Davies
https://www.navitron.org.uk/forum/index.php?topic=16798.msg191877

or for about £360 or £375 (incl) at normal prices:

http://www.solarproject.co.uk/
http://www.eco-nomical.co.uk/

I wonder whether making a significantly less efficient DIY panel is worthwhile. The efficiency of the panels is not so important from the point of view of the amount of energy harvested (you can always add more panels to compensate) but from the point of view of the length of the effective heating season. A DIY panel will likely give you good heating in summer which is completely useless for space heating applications whereas an evacuated tube panel is likely to extend that use well into the autumn and spring when it is useful.

PS, I have eight of the special-offer Navitron panels stashed away.

http://edavies.me.uk/2012/03/et/]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142512#Comment_142512 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142512#Comment_142512 Fri, 13 Apr 2012 13:26:25 +0100 djh Posted By: SteamyTeaIf it is pumped then just make sure that water is always pumped uphill, so pump at lowest point
On a solar thermal circuit the pump is always on the cold side. i.e. in this case it would be pumping downhill. :devil:

Posted By: Peter_in_HungaryI would not pump it - gravity is simpler and is self regulating.

But gravity also requires larger diameter piping and the pipe is a major source of heat loss, even if well insulated. :devil:

Posted By: tonyit will work well in summer but in winter only a bit.

Yup.

Posted By: Ed DaviesI wonder whether making a significantly less efficient DIY panel is worthwhile.

Yup.

But if it's just an experiment, have fun!

PS Steamy, Peter, just trying to start a fight :tongue:]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142522#Comment_142522 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142522#Comment_142522 Fri, 13 Apr 2012 14:28:02 +0100 jamesingram DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142527#Comment_142527 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142527#Comment_142527 Fri, 13 Apr 2012 15:11:08 +0100 tony
would take several lifetimes to pay for ET to heat a towel rad.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142531#Comment_142531 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142531#Comment_142531 Fri, 13 Apr 2012 15:31:35 +0100 Ed Davies Posted By: tonyefficiency is almost irrelevant when the heat is coming for free.

Indeed. But if the panel is so inefficient that it loses almost all the heat it receives during the times of year when it would be useful...

And even a DIY panel isn't quite free - even if it's totally made from available scrap materials there might be other uses for them.

This is written by somebody who has made a small DIY solar warm-air panel which did produce a little bit of useful heat this morning. However, it's only in the last few weeks that it's begun to do so this year and only on a few bright days. It's not ideally sited (east facing and shaded by a hill when the sun's low) so it's not an entirely fair comparison but it was producing nothing on a day when an ET tube outside was heating water at a rate equivalent to about 100 W/m².]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142544#Comment_142544 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142544#Comment_142544 Fri, 13 Apr 2012 16:35:37 +0100 budbecks
Thanks for all your comments and advice.

This is just an experiment and wether or not it will work for me who knows ! But 99% of the materials are free and i can do all the work myself. Even if i had to pay for a few things i wouldn't mind. If i get any heat at all i would be made up !

Only time will tell, I will however let you know whether or not any part of it works. Interesting little project i think.

Cheers all.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142549#Comment_142549 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142549#Comment_142549 Fri, 13 Apr 2012 17:11:37 +0100 joe90
http://www.builditsolar.com/index.htm]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142576#Comment_142576 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142576#Comment_142576 Fri, 13 Apr 2012 21:59:49 +0100 SteamyTea Posted By: djhOn a solar thermal circuit the pump is always on the cold side. i.e. in this case it would be pumping downhill.
I will bow to superior knowledge on this, but would need to know why.
I really cant think why it would matter where the pump is as long as no air gets drawn into it.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142585#Comment_142585 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142585#Comment_142585 Fri, 13 Apr 2012 23:08:39 +0100 Ed Davies DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142591#Comment_142591 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142591#Comment_142591 Sat, 14 Apr 2012 05:53:17 +0100 SteamyTea Posted By: Ed DaviesI think it's just a matter of extending the life of the pump by running it cooler.
That would make sense, so on a pumped system with the collector and vent higher than the radiator (or on the roof), the pump would usually be at the lowest point (and the coldest) then.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142672#Comment_142672 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=142672#Comment_142672 Sat, 14 Apr 2012 18:03:08 +0100 djh Posted By: Ed DaviesI think it's just a matter of extending the life of the pump by running it cooler.
Indeed so, and especially if the collector stagnates and steam comes along the hot side!]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143008#Comment_143008 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143008#Comment_143008 Tue, 17 Apr 2012 01:49:34 +0100 wookey
I'm with Ed - get a decent panel. And it makes sense to connect it to your hot water cylinder rather than one radiator.
Solar hot water is really good, but it'll work a whole heap better if you do it properly.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143630#Comment_143630 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143630#Comment_143630 Sat, 21 Apr 2012 21:39:10 +0100 budbecks
ITS AN EXPERIMENT !!!!!

If i spend money, then i spend money, no big deal. Worse things have happened at sea !!

i dont have room or anywhere to put any evac panels (well not without a lot of work) and then thats where you DO start spending money. If you read, 99% of the materials i already have or can get hold of completly free of charge. I may spend a little but thats fine by me.

Im on the way to having a new combi fitted so instead of connecting this to 1 towel rad i am going to connect it to the existing hot water cylinder and then to a rad to see what happens.

Its an interesting project for me and if it doesn't work then i have lost no money from my wallet :)

Thanks for the advice]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143646#Comment_143646 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143646#Comment_143646 Sun, 22 Apr 2012 11:39:30 +0100 Ed Davies DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143649#Comment_143649 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143649#Comment_143649 Sun, 22 Apr 2012 12:04:45 +0100 GaryB
Experiments are welcome and are of interest to both members and guests - please let us know the outcome, whether positive or negative.]]> DIY Solar project connection help https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143680#Comment_143680 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=8928&Focus=143680#Comment_143680 Sun, 22 Apr 2012 19:07:23 +0100 budbecks
Of course, not a problem. wont be for a while but i will let you know the outcome.

Cheers all.]]>