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Larry bought 2 ECO-47-1500-20 panels and other components for his system at the end of 2006.  For reasons of space he decided to use two hot water cylinders, his existing 130 litre tank and an additional 90 litre tank in the loft acting as a preheating system.  He used a Resol AX controller to circulate water between them when the preheat cylinder was hotter than the main cylinder, and a BS Pro controller for the solar circuit.  Larry opted to use separate components rather than a pump station.  As can be seen from the photos, Larry has used a lot of ingenuity with this system.  I like the idea of using magnets to make the carrier for the controllers removable for easy access.  Note also the very robust stand he has made for one of the panels.  Unfortunately we were out of stock of the flat roof stands when he needed one.

Here you can just see the panel on the flat roof of the garage.

Here is a close up view of a panel.  Note the chains, in case of unexpectedly strong winds!

A neat job!  This is the preheat cylinder, showing the two controllers, pump and the expansion tank.

This is a view of the magnetically mounted controller panel.  Larry writes:
"The panel with the Resol controllers mounted on it is secured by magnets;
and is held by two strips of angle iron upon which it can be slid to any
convenient position, or lifted off altogether to provide easy access to the
area behind, or laid flat to make it easier for me to see what I am doing
when I am playing with it".

Here are some additional views of the plumbing.  Note how Larry used plastic trunking to keep the pipe runs neat.



Larry writes: "Three 15mm pipes running to outside wall, in plastic trunking. Trunking is mounted on length of wood scarfed down to provide slight slope to assist system air removal. All pipework slopes for same reason.
Also shows 22mm. pipe running along the outside of trunking; This being the
pressure/temperature relief pipe from  the tundish".

Note that it is always good practice to lay pipework in such a way that there is a continuous slight slope up towards the air bleed point.

Larry needed one more tapping into his preheat tank than he had.  He solved the problem with this neat adaptation of an immersion heater blanking plate.

Here are some close up pictures of the stand Larry made.  Note the weight used to keep it in place.


Thanks to Larry for the pictures and information.

Update 20/7/07

Larry has decided to modify his installation and mount his panels on his house roof to avoid a partial shading problem during a part of the day.

He writes:

"Hi Simon

...and the use of cardboard tubes and old coat hanger wire gave security and
protection to the tubes when getting them up there.
I have the Resol controller set up that S1 is the solar panels, S2 & S3 are
the 90 litre pre-heater cylinder, S4 is the 130 Litre cylinder in the
kitchen". (Larry is referring to the temperature sensors here).
"The switching points for channel 1:- S1 & S2 are as supplied 6 deg. on, and
4 deg. off.  and channel 2 :- 6 deg. on & 2 deg. off.

Channel 2 controls the cycling pump between the 90 litre cylinder and the
130 litre cylinder, The converted immersion heater bosses in both tanks are
used for this.
The temperature of the cylinders is monitored at the level of the cycling
points, When the pre heat cylinder exceeds the main service cylinder by the
set level of 6 deg. cycling starts and continues until the switch off point
of 2 deg. is attained. "Normally about 2 minutes".
The water inlet to the main service cylinder, is internally directed over
the top of the boiler heating coil, and piped down to the very bottom of the
cylinder, thus, the lower level water within this cylinder, is fully cycled
with the pre-heat cylinder, without disturbing any warmer water that may be
above it.
We find that the use of water during the evenings causes little change to
the main cylinder temperature as it is the pre-heat cylinder that accepts
the replenishing cold water.
The heat dump Resol three port electrically driven valve, is controlled by a
standard immersion heater thermostat, and set to 70 deg. " The Resol
controller channel "SX1". was also raised to a higher shut down value of  75
The system appears to be most satisfactory and may be of use to those who,
like me, only have a single heating coil in their cylinder. Indeed, I think
there are some advantages to be had by such an installation".


Larry installing the tubes in the new panel.  Note his safety harness attached to his chimney.  He used a cardboard tube to avoid any damage to the collector tubes while lifting them up to the roof.


The Heat Dump motorised valve in place in the loft.


The immersion heater thermostat Larry used to control his heat dump circuit.


This is the smaller preheat cylinder which Larry uses to feed his main hot water cylinder.  He used this scheme mainly because there was no room for a single larger cylinder.


The main hot water cylinder.


The finished installation from the outside. 


Thanks again for the update, Larry.


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Last modified: 05-06-09