Have you ever wondered what’s going on inside those boxes? Take a look!
What do all these bits do? As we explain here, the heat pump takes heat energy from the ground, or the air or water – yes, this works even on a freezing cold day!
The evaporator then uses the heat energy to turn the refrigerant into gas (just like water becoming steam but at a much lower temperature.
With a small amount of extra energy, usually provided by electricity, the compressor compresses the refrigerant gas to a high pressure, which leads to a rise in temperature.
The by now hot and highly pressurised refrigerant gas passes through the condenser. The condenser allows the refrigerant to release heat into the heating system for the house. As a result, the refrigerant then turns back from a gas into a liquid state, its pressure is lowered by the expansion valve, and the whole thing starts again.
