Skip to content
A heat pump is a system that moves heat from one place to another instead of generating it from scratch. In the summer, it pulls heat out of your home and dumps it outside — just like an air conditioner. In the winter, it reverses the process, pulling heat from the outdoor air (yes, even cold air has heat energy) and moving it inside.
Think of it as a two-way air conditioner. One system, year-round comfort.
Here in Upstate South Carolina, heat pumps are one of the most popular HVAC systems we install — and for good reason. Our mild winters make them incredibly efficient compared to traditional furnaces.
How Does a Heat Pump Actually Work?
Every heat pump has four main components:
Compressor — The heart of the system. It pressurizes refrigerant to move heat.
Condenser coil — Releases heat (outside in summer, inside in winter).
Evaporator coil — Absorbs heat (inside in summer, outside in winter).
Reversing valve — The magic piece that lets the system switch between heating and cooling modes.
Here’s the simple version: Refrigerant flows through the system in a loop. When it evaporates, it absorbs heat. When it condenses, it releases heat. The reversing valve just changes the direction of flow, so the same system can heat or cool your home.
What Powers a Heat Pump?
Heat pumps run on electricity. Unlike a gas furnace that burns fuel to create heat, a heat pump simply uses electrical energy to move existing heat. This is why they’re so efficient — moving heat takes far less energy than creating it.
A modern heat pump can deliver 2-3 times more heating energy than the electrical energy it consumes. That efficiency is measured by something called HSPF2 (Heating Seasonal Performance Factor) for heating and SEER2 for cooling.
Types of Heat Pumps
Air Source Heat Pumps (Most Common)
This is what most homeowners in the Greenville-Spartanburg area have. It transfers heat between your home and the outdoor air. Modern air source heat pumps work effectively down to about 25-30°F before needing backup heat — which is fine for most South Carolina winters.
Geothermal (Ground Source) Heat Pumps
These use the constant temperature of the ground (about 55°F year-round in SC) instead of outdoor air. They’re more efficient but cost significantly more to install because of the underground loop system. We install these too, but they’re less common due to the upfront cost.
Ductless Mini Split Heat Pumps
Same technology, just without ductwork. These are great for additions, garages, sunrooms, or homes without existing duct systems. Each indoor unit handles one zone, giving you room-by-room temperature control.
How Do Home Heat Pumps Work in Winter?
This is the question we get the most: “How can it pull heat from cold air?”
Even when it’s 30°F outside, there’s still heat energy in the air. A heat pump’s refrigerant evaporates at extremely low temperatures, so it can absorb that heat and concentrate it. The compressor then pressurizes the refrigerant, which raises its temperature significantly — enough to heat your home.
It’s the same principle your refrigerator uses. Your fridge pulls heat from the cold interior and dumps it out the back. A heat pump in winter does the same thing, just with outdoor air.
When temperatures drop below the system’s effective range (usually the low 20s for standard models), the system switches to auxiliary electric resistance heat or, in dual fuel setups, a gas furnace kicks in.
Can a Heat Pump Handle South Carolina Winters?
Absolutely. Upstate SC winters are mild enough that a heat pump handles heating duties 90%+ of the time without needing backup. Our average winter lows are in the 30s, and heat pumps are most efficient above 25-30°F.
Some of the newer variable-speed heat pumps from manufacturers like Carrier, Trane, and Lennox can maintain efficiency down to 0°F or below — though we rarely see those temperatures in Greenville or Spartanburg.
For the handful of nights each winter when we dip into the teens, your system’s auxiliary heat or emergency heat kicks in automatically. You don’t have to do anything.
Heat Pump vs. Furnace: Quick Comparison
For most Upstate SC homeowners, a heat pump is the better choice:
Efficiency: Heat pumps are 2-3x more efficient than electric furnaces and more efficient than gas furnaces at moderate temperatures
One system: Heats AND cools — you don’t need a separate AC unit
Lower operating costs: Especially with SC’s relatively mild winters
Tax credits: Many heat pumps qualify for federal tax credits under the 25C provision (up to $2,000)
A gas furnace might make more sense if you already have gas infrastructure and regularly see extended periods below 20°F — but that’s rare here in the Upstate.
What Does a Heat Pump Cost?
In the Greenville-Spartanburg area, a standard air source heat pump system typically costs:
Entry level (Lowest SEER): $8,000 – $10,000 installed
Mid-range (Mid SEER): $10,000 – $14,000 installed
Premium (Higher SEER, variable speed): $14,000 – $20,000+ installed
These prices include the outdoor unit, indoor air handler, thermostat, labor, and permits. Your actual cost depends on your home’s size, ductwork condition, and the specific equipment selected.
Check out our full pricing guide: [How Much Does a Heat Pump Cost to Install?]
How Waldrop Can Help
At Waldrop Plumbing Air Electric, we’ve been installing heat pumps in the Upstate since the 1970s. Our NATE-certified technicians can evaluate your home, recommend the right system size and efficiency level, and handle the complete installation.
We also offer Club Wally, our maintenance membership, which includes two tune-ups per year to keep your heat pump running at peak efficiency. Regular maintenance extends the life of your system and catches small problems before they become expensive repairs.
Ready to learn more? Call us at (864) 536-0887 or schedule online at www.callwaldrop.com/schedule/ — we’ll give you a straight answer about whether a heat pump is right for your home.
