There are two types of collectors on a solar hot water system – flat panel or evacuated tubes. Let’s talk about evacuated tubes.
- A tube absorbs solar energy and converts it to heat.
- A tube consists of two layers of glass with a vacuum between the layers which insulates against heating loss.
- A copper vacuum pipe transfers the heat from within the evacuated tube up to the copper header pipe inside the insulated manifold box.
- A pump circulates water from the storage tank to the copper pipe and heats the water. The solar heated water is then pushed down into the storage tank ready for use.
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Thermann Evacuated Tube Diagram
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Apricus Evacuated Tube Diagram