5 ms·Why would it do that? The heat exchanger is placed outside.by ulrikrasmussen 4y agoWhy would it do that? The heat exchanger is placed outside.thaeli 4y agoHeat pump water heaters mostly draw from room air.jacobolus 4y agoCommon heat pump water heaters (often called “hybrid”) have a heat exchanger on the top of the tank, and pull heat out of the surrounding air.