Dual Fuel Technology: Precise Heating

Dual fuel heating with a heat pump and gas furnace

Every once in a while with indoor comfort, you CAN have it all! Precise, energy-efficient indoor comfort for every month of the year is like having your cake and eating it too!  When properly installed and configured, a dual fuel technology indoor comfort system offers the incredible combination of year-round comfort and energy-efficient performance!

The Dual Fuel Set-Up


A dual fuel system may come in the form of a packaged unit or a split system with two energy sources: the electric heat pump and a gas furnace. Dual fuel technology combines the cooling and heating performance that you get from a heat pump with the consistent heating capacity of a gas furnace. What makes this system so precise and energy efficient for heating is that it seamlessly alternates between the two energy sources for heating comfort, depending on your specific outdoor conditions.

How Dual Fuel Works


When the thermostat or control system calls for cool air, the heat pump unit functions just like a central air conditioner, it is designed to keep your home cool and comfortable even on extremely hot days.


When your home needs moderate heating output, the heat pump reverses the refrigerant flow to provide warm air in your home and operates like a typical heat pump. In a dual fuel system, if the heating demand exceeds the preset heating capacity of the electric heat pump, the heat pump pauses, and the gas furnace takes over until the indoor temperature reaches the desired temperature on your thermostat or control system.1

The system's switch point from the heat pump to the gas furnace can be set on the thermostat or control system by you or your dealer. Even on extremely cold days in winter, your dual fuel system is designed to provide energy-efficient, reliable, and consistent heat.


Energy Costs and Efficiency


Because certain energy sources, like electricity and natural gas,  operate most efficiently during specific weather conditions, a dual fuel system may maximize efficiency, and cut heating bills.


Yet, heat source efficiency is only part of the equation. The cost of electricity and natural gas in your location can affect the cost-effectiveness of a dual fuel system. “Prices of basic energy (natural gas, electricity, heating oil) are generally more volatile than prices of other commodities,” says the Energy Information Association.2 Energy prices typically vary by location because of the proximity to power plants, local distribution costs, and pricing regulations.  For example, in 2015 the annual average electricity price in Hawaii was estimated at 26.17 cents per kWh and 7.41 cents per kWh in Washington.3


When a dual fuel system's switch point can be determined by you or your dealer, the specific energy source pricing can be incorporated into the cost and efficiency equation.  If switching from the heat pump to the gas furnace reduces the time required to get to your set temperature, your energy cost of operation may decrease, and your comfort level may increase. Although the electricity may cost less than the natural gas in some areas, it may cost you more if your heat pump has to operate longer to meet your indoor temperature needs.


The flexibility of using a heat pump and a gas furnace may provide the homeowner with energy cost savings. However, it is important to learn the utility pricing options from your local utility provider(s) and then discuss the potential savings a dual fuel system might offer with your licensed professional HVAC dealer.

Dual Fuel Installation Options


If you are looking to replace your air conditioner with a heat pump, your professional licensed HVAC dealer may be able to upgrade your system configuration so that your new heat pump works in conjunction with your existing furnace system. If you are not currently utilizing natural gas as a heating source but it is an option is your area, homeowners interested in dual fuel systems may be able to add a high-efficiency gas furnace. The gas furnace would be the secondary heat source instead of using the heat pump's electric heat strip when the temperatures drop. 


To find out whether a dual fuel system is an option for your home and how you may benefit, talk to your professional licensed HVAC dealer.

Stay Warm with Goodman


1 U.S. Department of Energy. Air-Source Heat Pumps. n.d. https://energy.gov/energysaver/air-source-heat-pumps. 26 April 2017.

2 U.S. Energy Information Administration. "Why Do Natural Gas Prices Fluctuate So Much?" n.d. U.S. Energy Information Administration. https://www.eia.gov/pub/oil_gas/natural_gas/analysis_publications/why_do_prices_fluctuate/html/ngbro.html. 28 April 2017.

3 U.S. Energy Information Association. Factors Affecting Electricity Prices. n.d. https://www.eia.gov/energyexplained/index.cfm?page=electricity_factors_affecting_prices. 26 April 2017.