When a hard freeze rolls through the Bayou City, our heating systems are suddenly asked to do a job they rarely practice for.
Houston isn’t exactly built for the "frozen tundra" lifestyle. Most of our homes are designed to breathe through swampy humidity and survive long, triple-digit cooling seasons, not to endure sustained freezes. When a hard freeze rolls through the Bayou City, our heating systems are suddenly asked to do a job they rarely practice for. That’s usually when small, hidden hiccups turn into full-blown system failures.
During a hard freeze, your heater works overtime—running longer, cycling more frequently, and operating at peak demand. Systems that seemed perfectly fine during a mild December can give out fast once the mercury drops into the 20s. For many of us, the problem isn’t that the heater is "old"—it’s just that it has never been tested under this kind of stress.
These cold snaps have a way of exposing installation shortcuts, skipped maintenance, and airflow issues that stay invisible on a normal 50-degree night. From frozen drain lines to cracked heat exchangers, the cold finds the weak points. Knowing what’s happening under the hood—and how to prep—can keep you from waiting on an emergency heating repair list when HVAC crews are stretched thin across the city.
In the North, heaters run consistently for months. In Houston, they often sit idle, gathering dust for three-quarters of the year. When a freeze hits, these systems go from zero to sixty almost overnight.
This sudden workload brings a few common headaches:
To ensure your system is ready for these sudden shifts, regular HVAC maintenance is the best line of defense for year-round reliability.
Hard freezes tend to cause the same few "usual suspect" problems across Houston neighborhoods, regardless of how new the home is.
Gas furnaces often fail because the ignition systems aren't used enough to stay clean. Dust or moisture can prevent the burners from lighting correctly. If it fails a few times in a row, the system "locks out" for safety—one of the top reasons for service calls.
High-efficiency furnaces produce condensation that needs to drain away. During a hard freeze, these drain lines can freeze solid. If the water can't get out, the furnace shuts down to prevent a flood. This is a huge issue in homes with drain lines running through uninsulated attics or garages.
Heat pumps are champions in 40-degree weather, but they lose steam in extreme cold. They often switch to "auxiliary heat" (electric heat strips), which strains the system and your wallet. If you are noticing a decline in performance, it may be time to consult a professional about heat pump repair.
Cold weather can be the "final straw" for a glitchy thermostat. If a sensor can’t read the room correctly, the system might "short-cycle" (turning on and off rapidly) or refuse to kick on at all.
In many parts of the country, furnaces sit in insulated basements. In Houston, they are often tucked away in vented attics. This means your heating equipment is essentially sitting "outside" in the cold. When temperatures drop below freezing, the air surrounding your furnace is just as cold as the air in your yard.
This exposure causes the metal components and control boards to operate in an environment they aren't shielded from. Furthermore, if your ductwork has even minor leaks, it’s pulling in that freezing attic air or leaking out the heat you’ve already paid for before it ever reaches your bedroom. This creates a "losing battle" scenario where the heater is technically working, but the house never gets warm.
When your heater runs nonstop, the meter spins just as fast. Between longer run times and the use of auxiliary heat, it's common to see a utility spike within just a few days of a freeze. Heat leaks through gaps in insulation, air leaks around doors, and single-pane windows all force your system to work harder than necessary.
If your heat goes out, please stay safe. We often see folks turn to space heaters or even kitchen ovens to stay warm. While space heaters are okay if kept away from curtains and pets, never use a gas oven for heat, as it poses a major carbon monoxide risk.
Essential Safety Steps:
The biggest difference between a heater that survives the night and one that quits is routine care. A professional furnace maintenance check-up usually includes:
Why does my heater stop working specifically when it’s freezing? The extra workload exposes dirty components or frozen drain lines that wouldn't be an issue during a milder chill.
Can a heat pump handle a Houston freeze? Yes, but it won't be as efficient. It will likely rely on its "emergency" or "auxiliary" heat mode to keep you comfortable, which is more expensive to run.
Should I leave my heater running overnight? Absolutely. Trying to "save energy" by turning it off at night can lead to frozen components and makes it much harder for the system to recover the next morning. It also keeps your internal pipes slightly warmer.
What is that "burning smell" when I turn the heat on? If it's the first time you've used it in a while, it’s likely just dust burning off the heat exchanger. However, if the smell persists or smells like melting plastic/electrical components, turn it off and contact us immediately.
Hard freezes act like a "stress test" for our homes. They expose everything from leaky ductwork to aging components. By investing a little time in maintenance and sealing up drafts now, you’re much more likely to stay cozy when the next Arctic front rolls through. As our weather patterns become more unpredictable, proactive care isn't just a suggestion—it’s the best way to protect your home and your family. If your current system is struggling to keep up, it might be time to explore a more reliable furnace installation to ensure your home stays warm for years to come.
