Solar energy water heating panel - has solar panel forming top of water tank with pumped or thermosiphon flow between two units
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Solar energy pick-up
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Water heater with solar energy collector - has return from solar heater discharging into bottom of reservoir with thermostatically controlled electric heater in upper part (BR 6.6.78)
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Solar heated water tank - has plug in mouth of tank for all electrical connections and water circulation tubes
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Combination solar and electric heater
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Filter back-washing - uses suction to increase flow of back-wash water