With frequent (and sometimes drastic) weather changes, it's often difficult to know when the appropriate time is to turn on ...

A heat pump is an energy-efficient alternative to a furnace and air conditioner ... your furnace creates hot air and blows it through your home. The primary components of a furnace are the ...

One startup, Ireland-based Nexalus, argues that its hot-water approach ... centers use for air conditioning. That still leaves the question of what to do with the excess heat.