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A dual fuel heat pump pairs an electric heat pump with a gas furnace. The heat pump heats your home on mild days, and the furnace takes over when it gets very cold. For many North Carolina homes that already have gas, it is a smart way to cut heating costs. Our heat pump service team can tell you if it fits your house.
Key Takeaways
- Two heat sources, one system. A heat pump and a gas furnace share one thermostat and one set of ducts.
- The system picks the cheaper fuel. It switches to gas at a set outdoor temperature called the switchover point.
- It fits the Piedmont climate. Many winter days around Belmont are mild enough for the heat pump to carry the load.
- You need gas or propane. Without it, a heat pump with electric backup heat is the usual choice.
- It also cools. The heat pump works as your air conditioner all summer.
What Is a Dual Fuel Heat Pump?
A dual fuel system is also called a hybrid heat pump. It has two main parts. Outside, a heat pump looks like a regular AC unit. Inside, a gas or propane furnace holds the blower and burners. A compatible thermostat or control board tells each part when to run.
In summer, the heat pump cools your home just like a central air conditioner. In winter, it runs in reverse and pulls heat from the outdoor air into your home. When the outdoor temperature drops below the switchover point, the heat pump steps aside and the furnace heats the house.
If you are new to heat pumps, our guide on how heat pumps work explains the refrigerant cycle in plain terms.
How a Dual Fuel System Decides Which Heat to Use
A heat pump moves heat instead of making it. That makes it very efficient in mild weather. The ENERGY STAR heat pumps page says a heat pump can deliver up to three times more heat energy than the electricity it uses. That is far more than electric resistance heat, like baseboard heaters or a furnace with heat strips.
As it gets colder, the heat pump has to work harder for the same heat. At some point, gas becomes the cheaper or more comfortable choice. That point is the switchover point, sometimes called the balance point.
- Above the switchover point: the heat pump heats the home.
- Below the switchover point: the gas furnace heats the home.
- During defrost: the furnace can run briefly so you do not feel cool air while the outdoor coil melts frost.
The installer sets the switchover temperature during setup. It is often somewhere around freezing, but the right number for your home depends on your equipment, your insulation and what you pay for electricity and gas. A good installer looks at all three instead of using a default setting.
Dual Fuel vs Other Heating Setups
| System | Mild Days | Very Cold Days | Needs Gas or Propane | Cooling |
|---|---|---|---|---|
| Dual fuel heat pump | Heat pump (very efficient) | Gas furnace | Yes | Yes |
| Heat pump with heat strips | Heat pump | Heat pump plus electric strips (costly to run) | No | Yes |
| Gas furnace with central AC | Gas furnace | Gas furnace | Yes | Yes, from a separate AC |
| Heat pump only (cold-climate model) | Heat pump | Heat pump at lower efficiency | No | Yes |
For a side-by-side look at the two main heat sources, read our post on heat pump vs furnace.
Are Dual Fuel Heat Pumps Worth It?
For a home that already has natural gas or propane, a dual fuel system is often worth it. The heat pump handles most of the mild Carolina winter cheaply, and the furnace covers the coldest nights without running costly electric heat strips. Homes without gas service usually do better with a heat pump alone.
Benefits
- Lower heating bills on most winter days, when the heat pump runs.
- Warmer air on cold nights. Furnace air feels hotter at the vents than heat pump air.
- Backup heat. If one side needs repair, the other can often keep the house warm.
- Less wear on each part. Neither the heat pump nor the furnace carries the whole year alone.
Drawbacks
- Higher upfront cost than a single system, since you buy two heat sources.
- More parts to maintain. Both the heat pump and furnace need yearly service.
- Gas is required. Running a new gas line adds cost if the house does not have one.
- Setup matters. A poorly set switchover point can erase the savings.
Talk to us at (980) 277-5122 if you want a straight answer for your house. We will look at your current system, your ductwork and your utility bills before recommending anything.
Who Should Choose a Dual Fuel System?
Dual fuel tends to fit best if:
- Your home already has a gas furnace and central AC, and the AC is due for replacement.
- You have natural gas service or a propane tank on site.
- You want the efficiency of a heat pump but like the feel of furnace heat on cold mornings.
- You currently run electric heat strips often and see high winter power bills.
It is usually not the best fit if your home is all-electric with no gas nearby, or if your furnace is brand new and your AC still has many years left.
How to Plan a Dual Fuel Upgrade
- Check your gas furnace. If it is in good shape, a new heat pump can sometimes be paired with it. Older furnaces may need replacing at the same time.
- Get a load calculation. The heat pump should be sized to your home, not to the old AC by default.
- Look at your ducts. Leaky or undersized ducts waste the savings from any new system.
- Pick a matched thermostat. It must support dual fuel control and an outdoor temperature reading.
- Set the switchover point. Base it on your rates and comfort, then review it after the first winter.
- Ask about rebates and payment options. Utility rebates and tax credits change often, so ask what applies the year you install. We also offer HVAC financing options for new systems.
Dual Fuel Heat Pump FAQs
How do dual fuel heat pumps work?
The heat pump heats your home until the outdoor temperature drops below a set switchover point. Then the control turns the heat pump off and fires the gas furnace. In summer, the heat pump cools the house.
Do you need a second source of heat with a heat pump?
Most heat pumps have some backup. In a standard system, that is electric heat strips. In a dual fuel system, the gas furnace is the backup. The TVA dual fuel explainer describes the gas furnace as the heat source that takes over in deep cold.
Is it okay for a heat pump to run all night in winter?
Yes. Heat pumps are designed to run long, steady cycles, especially in cold weather. Long run times are normal. Constant running with a cold house is not, and that is worth a service call.
Is a 2 stage heat pump worth the extra money?
A two-stage or variable-speed heat pump runs on low most of the time, which gives steadier temperatures and better humidity control. It costs more upfront. Whether it pays back depends on your home and how long you plan to stay.
What is the lifespan of a dual fuel heat pump?
Each side ages on its own. Because the heat pump and furnace share the heating load, neither runs all winter alone. Yearly service on both parts is the best way to reach a long life.
Find Out If Dual Fuel Fits Your Home
Call Gerald Griffin Heating and Cooling at (980) 277-5122 and ask for a dual fuel assessment. We will check your gas service, furnace age, ducts and bills, then show you the numbers for dual fuel, heat pump only, and furnace with AC. Gerald has worked in HVAC for more than 30 years, and we serve Belmont, Gastonia, Mount Holly, Stanley and nearby towns 24 hours a day. You can also request a system estimate online.
Gerald Griffin Heating and Cooling Services
902 Belmont Mt Holly Rd
Belmont, NC 28012
Phone: (980) 277-5122
Hours: Open 24 hours
NC Heating Contractor License #32307