How a Heat Pump Works in North Texas

By David Fish, Owner & Lead Technician, TX Lic. TACLB99535E · Last updated July 2026

A heat pump is an air conditioner that runs in both directions: in summer it moves heat out of your house exactly like any AC, and in winter a reversing valve flips the refrigerant flow so it pulls heat out of the outdoor air and moves it inside. It does not burn anything to make heat — it moves heat that already exists — which is why it can deliver more heat energy than the electricity it consumes. North Texas, with brutal summers and mild winters, is close to the ideal climate for the technology.

How does a heat pump make heat from cold air?

Even 30°F air contains usable heat energy — cold is relative, and refrigerant boiling through the outdoor coil runs colder than the outside air, so heat flows into it. The compressor concentrates that absorbed heat, and the indoor coil releases it into your ductwork. The supply air runs 90–105°F rather than the 120°F-plus of a gas furnace, so the system runs longer, gentler cycles that hold temperature steadily instead of blasting and coasting. Homeowners switching from a furnace sometimes mistake that gentler air for weak heating — it is a different delivery style, not a defect. If yours truly blows cold, see why is my heater blowing cold air.

When does a heat pump make the most sense here?

The DFW winter profile plays to a heat pump’s strengths: most heating hours happen between 35 and 55°F, exactly the range where heat pumps are at their most efficient. Because a heat pump replaces both your AC and your heat source in one machine, it fits naturally when your cooling system is due for replacement anyway — you are buying one system instead of two. All-electric homes and homes without natural gas service (a street-by-street reality in parts of Colleyville and newer developments north of Fort Worth) are the clearest cases, since the alternative is inefficient electric resistance heat on Oncor-delivered electricity.

What happens during a real cold snap?

Below roughly freezing, a standard heat pump’s output declines just as the house needs more heat, and auxiliary electric heat strips make up the difference — at a much higher operating cost. Our winters are mild but spiky: a week of 60°F afternoons, then an Arctic front drops us into the teens for three days. Those few days are when heat strips run and electric bills jump, and they are why sizing and system selection matter. Modern variable-speed and cold-climate models hold useful capacity far lower than older single-stage units, and a dual-fuel setup — heat pump paired with a gas furnace for the coldest hours — hedges the extremes. Frost on the outdoor coil is handled by an automatic defrost cycle; steam rising off the unit on a cold morning is normal, not a fire. One more Texas-specific note: thermostat configuration matters more on a heat pump than on any other system, because a thermostat that calls auxiliary heat too eagerly will quietly run the expensive strips on days the heat pump alone could handle — staging thresholds and outdoor lockout settings are worth asking about explicitly at installation.

What are the failure modes to know about?

The reversing valve is the one component a straight AC does not have, and when it sticks the system heats poorly or cools when it should heat. Undersized or leaky ductwork hurts heat pumps more than furnaces because of the lower supply temperature — a real issue with builder-grade attic duct runs in our slab-on-grade housing stock. And oversizing kills humidity control in summer. This is why a proper load calculation, not a tonnage match, should precede any installation.

What does this look like on a real project?

[PROOF: case snippet]

What is the next step?

If your AC or furnace is within a few years of replacement, get a heat pump quote alongside the like-for-like option and compare honestly. Our Heat Pumps team designs and installs across the area, including heat pump installation in Southlake, TX and heat pump installation in Keller, TX.

Keep learning: weigh the tradeoffs in heat pump vs. AC + furnace in North Texas, and if backup power for winter storms is on your mind, size it right with what size whole-home generator do you need.