Solar Heating System Design

A solar panel collector is mounted on the roof, usually facing south. A mixture of water and antiferring fluid circulates through the collector, picking up heat, and is pumped down to a coil fitted near the bottom of your hot water cylinder, heating the stored water indirectly, without mixing with it.

A controller monitors the temperature at the collector and in the cylinder, and only runs the circulation pump when the collector is actually hotter than the water below, so you're never using electricity to move heat the wrong way. Your boiler or immersion heater sits above the solar coil in the cylinder, automatically topping up the last few degrees when solar heat alone isn't quite enough.

The result is a system that runs itself: no daily intervention needed, and it simply contributes less on overcast days and more on sunny ones.