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Installation Guide

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Installation update:  After 12 months operation, this installation provided just over 4 MWh  (4000 kWh).  The exact figures reveal a figure of 34.55 kWh per tube per year.

Justin installed a large collector array for Simon, and writes:

"Simon Jackson contacted me in mid March to discuss the possible installation of a very large solar water heating system. The request was to heat the following stores.

  • A primary twin coil vented cylinder with 180 Litre water capacity, currently being heated using a conventional boiler and electric immersion heater.
  • A secondary single coil vented cylinder with 185 Litre water capacity.  The coil fitted into this cylinder was oversized to allow fast transfer of heat to the water store.
  • A indoor swimming pool which was currently heated of a gas boiler

 The basic idea of the system was to give Simon 360 Litres of hot water and due to the size of the array he would be guaranteed this for the vast majority of the year.  A Resol E controller was installed allowing full control of the system and if required would allow the addition of a 4th water store in the future. This controller will allow Simon to change the priority loading of the system as he lives in a house that sometimes only has two occupants in.  He may choose to only heat the primary store and then request the system goes straight onto to heat the swimming pool. If on holiday he is likely to set the swimming pool to constantly be heated as there will be no requirement for hot running water. I would recommend that if you intend to keep modifying your system over time, go straight for the Resol E controller as it will do everything and more. The only downside is it has no graphic display but opts for a dropdown menu, I presume this is due to the fact you an only get so much information on a small screen. The controller was programmed to bring the Primary and Secondary store up to 60 Degrees. It would then use any surplus heat available to heat the indoor swimming pool.

The Bowman Swimming Pool heat exchanger was positioned before the boiler exchanger, this allowing the solar generated energy to enter the swimming pool loop first and then allow the boiler to increase the temperature if required. An Auxiliary Relay was also fitted to allow the swimming pool pump to operate at the same time as the solar pump to allow flow through the Bowman Exchanger.

Simon also wanted to know exactly how much energy the system was capturing, so I opted to fit a Resol V40 2.5 Flow-meter along with 2 additional sensors. The flow-meter is positioned just after the pump station horizontal along with the first sensor. The second sensor is positioned on the pipe work between the collectors and the store enabling the controller to compare the differential between the 2 sensors.  This allows the system to calculate exactly how much energy has been created in KWH along with the hourly running time of each store. Simon will be able to assess where the energy is going and a total saving per year. I have advised him to record his readings at the end of each month and reset the counters.

System components as follows;

Primary Store            180 Litre Vented Twin Coil cylinder

Secondary Store       185 Litre Vented Single Coil cylinder

Third Store                 Indoor swimming pool

4 x Eco-58-1800-30 collectors

Resol D2S twin pumpstation

Resol RF Pumpstation

Resol E Controller

Resol Flow-meter V40 2.5


Bowman heat exchanger

40 Litres of Glycol

Auxiliary Relay for swimming pool pump

I would like to thank Simon and Trisha for allowing me to install at their property. Simon worked extremely hard with myself to complete the install.

Just to verify the highly competitive cost of this system, excluding the cylinders it worked out at only £1000.00 more than a local solar company was offering to install a simple 1 panel system for!!!  Now how’s that for value?"


Thanks to Simon and Justin for this information.


Send mail to SW@eco-nomical.co.uk with questions or comments about this web site.
Last modified: 05-06-09