Heat shifters & heat exchange ventilators

 

These are simple fans or fan and duct combinations that take the excess heat that accumulates near the ceiling in one room and use it to heat a second room. They actually work quite well, and almost heat the second room for free.

You can buy them as kits, or make them up yourself from a fan, a bit of ducting and a vent cover or two.

These devices are far more common in the energy-efficient homes of Europe than they are in Australia. When a home is tightly sealed, ventilation can be important to remove some of the stale air from the home.

However, simply removing air and replacing it with cold air from outside has the effect of wasting heat and cooling the home-not what you want in an energy-efficient home.

Heat exchange ventilators work by extracting heat from the outgoing stale air and using it to warm the incoming fresh but cold air, thus reducing the amount of energy needed to maintain a suitable air temperature in the home.