How Does an Air Source Heat Pump Work?
- Heat pumps transfer heat by circulating a substance called a refrigerant through a cycle of evaporation and condensation.
- A compressor pumps the refrigerant between two heat exchanger coils. In one coil, the refrigerant is evaporated at low pressure and absorbs heat from its surroundings.
- The refrigerant is then compressed en route to the other coil, where it condenses at high pressure. At this point, it releases the heat it absorbed earlier in the cycle.
- Refrigerators and air conditioners are both examples of heat pumps operating in the reverse (cooling) mode. A refrigerator is essentially an insulated box with a heat pump system connected to it.
- The evaporator coil is located inside the box, usually in the freezer compartment. Heat is absorbed from this location and transferred outside, usually behind or underneath the unit where the condenser coil is located.
- Similarly, an air conditioner transfers heat from inside a house to the outdoors.
- Heat pumps can provide year-round climate control for your home. Since the air outside always contains some heat, a heat pump can supply heat to a house even on cold winter days.
- In fact, air at –18°C contains about 85 percent of the heat it contained at 21°C.