Heat pump
The heat pump is an air
conditioner that can be used
either for heating or for cooling
systems for buildings.
In plumbing applications, a heat pump is sometimes used to heat
or preheat water for swimming pools or domestic water heaters.
Geothermal heat pumps use
the ground and water to work
as the condensers and
evaporators. They work in the
same manner as an air to air
heat pump, but instead of
indoor and outdoor coils they
use the earth as natural
evaporators and condensers.
These are very eco-friendly
and are a cheaper alternative
in the long run due to lower
operating cost.