wunder beta

HP How Heat Pumps Work

Follow refrigerant, reversing valves, defrost, and ground loops as a heat pump moves energy through the seasons.

lessons

~20 min

to learn

🔬 Science

subject

Adults

level

Start the course →

What you’ll learn

The Big IdeaDefine a heat pump as a machine that relocates heat.A refrigeration loop moves ambient heat indoors or outdoors using electrical work.
The Refrigeration LoopTrace the four main stages of the cycle.Evaporation, compression, condensation, and expansion repeat in a sealed circuit.
The Cold SideExplain why cold air can still be a heat source.A colder refrigerant can absorb heat from outdoor air, though performance changes with weather.
Reversing the SeasonExplain how one machine heats and cools.A reversing valve swaps the indoor and outdoor jobs of the coils.
Compression and CondensationConnect compressor work to indoor heat delivery.Compression creates hot high-pressure vapor that can release heat indoors.
DefrostDescribe normal defrost operation and its limits.A short reverse cycle melts frost that would block an air-source outdoor coil.
Measuring EfficiencyInterpret COP without treating it as a guarantee.COP compares useful heat delivered with electrical work under stated conditions.
Ground and Water SourcesCompare stable ground or water sources with outdoor air.Ground loops can provide steadier source temperatures but require site-specific installation.
Controls and BackupRelate controls and supplemental heat to changing loads.Thermostats, modulation, defrost, and backup stages coordinate capacity and comfort.
The Whole SystemConnect equipment performance to the building and service context.Envelope, distribution, sizing, maintenance, and refrigerant handling shape real results.

Questions this course answers

What is a heat pump's central job?

A heat pump uses electrical work to relocate ambient heat through a refrigeration cycle.

Put the basic heat-pump cycle in order.

The refrigerant absorbs heat, is compressed, rejects heat, and expands before repeating the loop.

Why can a heat pump deliver more heat than the electrical energy it consumes?

The electrical input powers the transfer; it is not the only source of the heat delivered indoors.

Grounded in trusted sources

U.S. Department of Energy, Heat Pump Systems: https://www.energy.gov/energysaver/heat-pump-systems
U.S. Department of Energy, Heat Pumps: https://www.energy.gov/heat-pumps
ENERGY STAR, Air-Source Heat Pumps: https://www.energystar.gov/products/air_source_heat_pumps
U.S. EPA, Purchasing and Repairing Home Air-Conditioners or Heat Pumps: https://www.epa.gov/ods-phaseout/purchasing-and-repairing-home-air-conditioners-or-heat-pumps
ASHRAE Handbook, Unitary Air Conditioners and Heat Pumps: https://handbook.ashrae.org/Handbooks/S16/IP/S16_Ch49/s16_ch49_ip.aspx
Wikimedia Commons, Heat pump media pages: https://commons.wikimedia.org/wiki/Category:Geothermal_heat_pumps

Every Wunder lesson is built from real, reputable sources — never invented.

Related Science courses

DRHow Clothes Dryers Work VCHow Vacuum Cleaners Work ELHow Elevators Work ❄️How Air Conditioners Work ❄️How Refrigerators Work WMHow Washing Machines Work ESHow Escalators Work ADHow Automatic Doors Work

Wunder is a personalized learn-anything platform — tell it any topic and it builds a beautiful, fact-checked course in minutes, with narration, a knowledge check, and a college-style University track.

Browse more Science courses · All topics · Home