The gold standard heat exchange equipment incorporates a heat pump so that (consider the winter case):

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Any moisture in the incoming air can be condensed and captured

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hot water can be pumped into the air exhaust pipe to maximise the energy dumped to the outside

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Any remaining heat in air being vented to the outside can also be captured, making the hot water generation more efficient.

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Energy nerds can have something to do in winter time.

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