The special felt cover F7 can be spliced with solar aluminum alloy collector OS20/22 and installed on a flat roof or wall. As long as the felt cover is spliced, the temperature of the fresh air entering the room can be increased: F7----about 10℃; F11----about 15℃; F20----about 20℃.
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Evacuated Glass tube solar Collector as an Air Heater by Vora, Chetan Parashottambhai, ISBN 9798889954675, ISBN-13 9798889954675, Like New Used, Free P&P in the UK
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Evacuated Glass tube solar Collector as an Air Heater by Vora, Chetan Parashottambhai, ISBN 9798889954675, ISBN-13 9798889954675, Brand New, Free P&P in the UK
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