How a Heat Pump Works

Overview

• Not a furnace or an air conditioner, but can both heat and cool a home.
• Utilizes a basic physics principle that has been in use for centuries.
• Functions as an all-in-one heating and cooling appliance.
• Consists of two main components: an indoor air handler and an outdoor heat pump.

Heat Pump Mechanism

• Compressor Function: Absorbs and releases heat.
• Summer Operation: Absorbs heat from inside and expels it outside, similar to an air conditioner.
• Winter Operation: Reverses process to extract heat from outside air and deliver it indoors.
• Heat Sources: Can absorb heat from air, ground, or water.

Efficiency and Energy Use

• Air-source Method: Most common and affordable.
• Energy Efficiency: Uses electricity to transfer heat instead of burning fuel; reduces energy consumption by about 50% compared to other heating appliances.
• Cold Air Heat Extraction: Can extract heat even from cold air, making it more efficient than systems that only produce either cool or warm air.
• Heat Movement: Moves heat rather than generating it, resulting in lower energy use.

Limitations

• Ideal Climate: Best for moderate climates; less efficient in regions with long, frigid winters.
• Temperature Threshold: Most effective at temperatures around 30°F.
• Cold Climate Solution: Can be coupled with a gas furnace in a dual-fuel system for colder regions.

Alternative Configurations

• Dual-Fuel System: In cold regions, heat pump works with a gas furnace.
  • In mild weather, the pump produces heat and the furnace circulates it.
  • In very cold weather, the furnace takes over.
• Air Handler Pairing: In hot climates, heat pump paired with air handler to distribute air.

Conclusion

• Viability Assessment: Homeowners should consult licensed heating-and-cooling contractors to evaluate the suitability of a heat pump for their home.

Author Information

• Joseph Truini: Former carpenter and cabinetmaker, writes about remodeling, woodworking, and tools. Contributing editor to Popular Mechanics, appears on Today's Homeowner TV and radio shows.

Note: Heat pumps are a significant step towards energy-efficient heating and cooling solutions, tailored to moderate climates but adaptable to various needs.