-- I have been looking at some archived items and web items about this.
Basically it seems fairly straight forward. I need a South facing solar heating panel with a grid of tubing filled with a non freezing fluid. A small pump then transfers this heated fluid to an indirectly heated cylinder (let's call it a solar tank) in the loft and plumbed in between the existing header tank and the existing hot water cylinder.
This is all very fine, but when the sun goes in cool water will be circulated which will then start to cool the solar tank. What I need is a pair of sensors that will detect when the water in the solar tank is hotter than the temperature in the solar panel and will then switch off the pump till the solar panel warms up again.
Has anybody tried this sort of heating supplement and addressed the particular problem of the switching control on the pump.
Any other tips.
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