When temperatures plummet, heat pumps may struggle to extract sufficient heat from the frigid outdoor air to maintain comfortable indoor temperatures. This is where a supplementary heating source comes into play. Options for supplementary heating include:

  • Electric Resistance Heating: Often built into heat pumps as an auxiliary heating system, this option can provide additional heat during extremely cold weather. However, it is less energy-efficient and can lead to higher electricity usage and costs.
  • Gas Furnaces: Integrating a heat pump with a gas furnace, a system known as a dual-fuel or hybrid heat system, allows for high-efficiency heating in mild weather and cost-effective, powerful heating during colder periods. The system automatically switches to the gas furnace when it becomes more economical than running the heat pump.

Advantages of Dual-Fuel Systems

A dual-fuel system combines the best of both worlds: the efficiency of a heat pump with the power of a gas furnace. Here are several benefits of this setup:

  • Cost Efficiency: By using the heat pump for most of the year and the furnace during extreme cold, homeowners can optimize their energy usage and reduce overall heating costs.
  • Environmental Impact: Reducing reliance on the furnace helps lower greenhouse gas emissions, as the heat pump is a more environmentally friendly option.
  • Comfort and Reliability: Dual-fuel systems provide a consistent, comfortable indoor environment by automatically selecting the most effective heating method based on current temperature conditions.

Implementation and Maintenance

To ensure the most effective operation and longevity of a dual-fuel system, professional installation and regular maintenance are crucial. Proper sizing, installation, and settings are key to maximizing the efficiency and effectiveness of the hybrid system. Homeowners should schedule regular maintenance checks to keep both the heat pump and furnace in optimal working condition.


For Philadelphia homeowners, adopting a heat pump supplemented by a gas furnace or another heating source offers a practical and efficient solution for year-round comfort. This approach not only caters to the unique demands of the local climate but also aligns with energy conservation and cost-saving goals. By understanding and utilizing these advanced heating technologies, residents can enjoy a warmer home during the winter without excessive energy costs.