Solar heating on the cheap

[emergencyman]

Although I am an experienced plumber , I know little about solar water heating but thinking of making one up on the cheap( £200 should cover it ) .
I have read this idea on the net . Make a wooden box say 6ft x 3ft , first fit loft insulation, ali or copper sheet attached to loads of 10mm copper , paint it all matt black and put a glass sheet over the top.
I assume then ( no more instructions) that I could place this box in the garden , run 2 pipes( 15 or 22?) up the wall and fit 2 essex boss to my cyliner . I assume no need for a pump as would be gravity circulation?
Would this work?
Its nothing I would consider doing for a real customer but more of a experiment , if it works and I can turn the gas boiler off then thats a bonus. I realise there should be more advanced controls, stats , valves etc but I just want something that works on a budget .
Would a panel that size do a 36x 18 cylinder?
I think in winter I would just isolate and drain down?
How many hours sunlight would it need.
Any thoughts?

 

[tsta]

If you placed the box about 2 miles from the sun, it may just work. Otherwise no.

 

[bobpape]

In the tropics a house with a flat roof and a "cold storage cistern" on it in full view of
the sun, will warm sufficently in a day to get a warm shower from it,

Your idea of connecting the "second primaries" directly or indirectly to a cylinder could provide some free heat but you would have to have a means of turning the "secondary primaries" off when the primary primaries kick in to finish the job,

The reason being that if left to circulate the hotter water in the cylinder would circulate back down to the garden coil and cool off,
As you know heat travels to cold,

 

[migoplumber]

emergencyman, your set up will work perfectly.. tho you have to be on hand everyday to open and shut valves, i made this set up when in spain myself, as an experiment, worked perfectly. however come nighttime my solar panel turned into a radiator taking the heat out of my cylinder and heating the world.
you can buy temperature sensors to place on your pipework, link in a cylinder stat and a 3 way valve with a time and a light sensing device. all stuff you can buy and make yourself.
if not a simple gate valve with expansion vessel and opver pressure works well, tho you do have to operate manually.

yes it works.

shaun

 

[emergencyman]

Cheers all,

I got the ideal last month in Lanzarote whilst having a wine on the balcony admiring the roofline, but obviously not thought it through.

To stop it circulating when cold outside I suppose I could use a room stat wired (somehow) to a 2 port valve? Or loop the pipework to prevent gravity circulation and fit a pump on a roomstat outside ?

In any event it seems it wouldn`t be sunny enough anyhow! nevermind on to my next idea.......

I was gonna put anti freeze in the central heating and place a coil of 10mm copper in an old freezer in the kitchen. Pipe up the 10mm coil as one would a rad.
When its too hot in the house turn the boiler off and plug in the freezer. Hey presto, instant air conditioning ( well cold rads) in every room.
How bigger freezer do you think I would need to reduce the air temperature by 10oC in each room?
I was thinking that if the rads are not big enough I could fit a small fan to each one to improve airflow( a bit like a Myson) .

emergencyman, your set up will work perfectly.. tho you have to be on hand everyday to open and shut valves, i made this set up when in spain myself, as an experiment, worked perfectly. however come nighttime my solar panel turned into a radiator taking the heat out of my cylinder and heating the world.
you can buy temperature sensors to place on your pipework, link in a cylinder stat and a 3 way valve with a time and a light sensing device. all stuff you can buy and make yourself.
if not a simple gate valve with expansion vessel and opver pressure works well, tho you do have to operate manually.

yes it works.

shaun

Sorry , posted same time as you . How big was the panel you made? Why would I need an expansion vessel ?
I suppose I could make one first with gate valves and modify it to motorised if it worked?

 

[Puddle]

however come night time my solar panel turned into a radiator taking the heat out of my cylinder and heating the world.


shaun

So what you are saying is you are totally responsible for global warming, Great,thanks alot
But seriously whets all this negativity , think diy system great idea to try emergencyman, what we need is some positive input

 

[migoplumber]

yes i alone am responsible for global warming, anyone want to buy a couple of air conditioning units, i have a mate (emergencyman ) who makes them good and cheap.

i made several panels and tried several different schematics to make my panel work,
i ended up with 2 panels 7ft by 4ft. ended up with a 12 volt switching actuators on a 2way valve just to shut the panel primary. the expansion vessel and blowoff were used in the same way as any boiler set up. the actuator was switched by a bulb thermostat linked to cylinder stat and outside temp stat. (all just switches at end of the day)

good luck
shaun

p.s. im very positive about idea!

 

[emergencyman]

Cheers Shaun,

I will post back here when I get stuck with the electrics. ( may be some time away)

I was thinking than rather use 2 essex bosses I couldjust connect to hot out and cold in near the cylinder?

I still dont see why the need for an expansion vessel, would it not expand in the F and E tank or was yours an indirect system?

Was the panels like this one? DIY Solar Panel

 

[migoplumber]

my panel had a 22mm feed top and 22m return bottom. inside was just a run of 22mm horizontally with 15mm vertical drops, just t'd off the 22mm.
about 10mm below the drops was a sheet of zinc painted with black matt stove paint, the glass was 6mm reinforced.
heat absobtion into the collector wasnt a problem.

f+e tank was removed, after first try and turned into closed system due to the fact that the water was nearly at boiling point and evaporated.

importantly bear in mind when you close the sytstem and put under pressure, water boils at different temps and reacts in different ways, causing some dangerous side effects!!

post a schematic so we can do some constructive criticism

your bringing me back some memories, might rebuild one my self!!

shall see if i can find my old drawings over the weekend and post myself.

shaun