• [A]
• [B]
• [C]
• [D]
• [E]
• [F]
• [G]
• [H]
• [I]
• [J]
• [K]
• [L]
• [M]
• [N]
• [O]
• [P]
• [Q]
• [R]
• [S]
• [T]
• [U]
• [V]
• [W]
• [X]
• [Y]
• [Z]

Heat pump

A heating and/or cooling appliance in which specialized refrigerant fluid in a sealed system is alternately evaporated and condensed, changing its state from liquid to vapor by altering its pressure. This phase change allows heat to be transferred into or out of the house.