How do I prepare my HVAC system for a North Texas cold snap?
The whole trick is a 15-minute test run before the freeze: heat verified, filter fresh, CO alarms tested, water shutoff found.
Test your heat before you need it: run it 15 to 20 minutes on a mild day and confirm warm air and a rising room temperature. Replace a dirty filter, keep vents open, clear debris from the outdoor unit, test your carbon monoxide alarms. Know where your water shutoff is.
What you can safely check
- Run the test run on a mild day: 15–20 minutes of heat, warm air at the vents, room temperature rising, no shutdowns mid-run (Q33), no alarming noises (Q34). Only the brief, fading dusty smell of first burn-off (Q39).
- Check the filter and replace it if dirty; open supply vents; make sure returns are not blocked by furniture.
- Test CO alarms in any home with fuel-burning system: press the test button, check the unit's age, replace batteries or expired units (Q98).
- Clear leaves and debris from around the outdoor unit by hand. Make sure heat pump meltwater has somewhere to drain (Q37).
- Locate your home's main water shutoff. Before you need it in the dark, in a hurry.
- Never use an oven, grill. Generator to heat your home. All three are carbon monoxide killers. A backup space heater stays attended, on a flat surface, away from bedding and curtains.
- Anything the test run exposes goes on a booking, not on a DIY list — ignition, gas. Refrigerant work are pro (Q63).
How this works
North Texas cold snaps arrive fast and hit hard. The pattern repeats every winter. Heating systems sit idle all summer. Then they fail on the first cold night. That is precisely when every HVAC company in the region is at its busiest, and waits are longest. Preparation is how you avoid joining that queue.
The centerpiece is the test run. Switch the thermostat to HEAT. Let the system run 15 to 20 minutes. Then verify two things: warm air at the vents. A room temperature that rises. A system that fails this gentle test has failed at the cheapest possible moment. You can book a normal inspection instead of an emergency call during the freeze (Q63). The test run also burns off the season's dust under controlled conditions. It does not become a smell mystery on the first cold night (Q39). Heat pump owners: watch a defrost cycle if the weather cooperates. Learn that the steam is normal (Q36).
Support the system around the edges. A fresh filter helps it breathe. Restricted airflow makes furnaces overheat and heat pumps underperform (Q33). Keep supply vents open and returns unblocked. Outside, the unit needs clear air. It also needs a drainage path for defrost meltwater (Q36, Q37).
Then comes the safety layer, which outranks comfort. If your home has any fuel-burning system, test your carbon monoxide alarms. Carbon monoxide is a poisonous gas with no color and no smell. Winter is its season. Furnaces run longest exactly when houses are sealed tightest (Q98). Also know where your home's main water shutoff is. A burst pipe during a snap does more damage than the cold itself. On the worst nights, open the cabinet doors under sinks so room heat reaches the pipes.
If the snap catches you anyway, keep the heat running. Do not let the house get deeply cold. Expect a heat pump to run long hours, with its auxiliary heat helping (Q38). Auxiliary heat is the backup heat that turns on automatically when the heat pump cannot keep up alone. That is normal, if pricier. Expect occasional defrost steam, too. If the system fails outright and the house cannot stay warm, say exactly that when you call. And if the indoor temperature keeps falling, relocate.
| When | Task |
|---|---|
| A mild day before the snap | 15–20 minute test run of the heat |
| Same day | Replace a dirty filter; open vents; clear unit debris |
| Same day | Test CO alarms; find the water shutoff |
| If the test run fails | Book a heating inspection before the freeze (Q63) |
| During the snap | Expect long heat-pump runs and defrost steam — both normal (Q36) |
When to call a professional
Call before the weather turns if the test run reveals weak heat, failed ignition, repeated shutoffs. Smells beyond the brief dust smell. That booking is a routine heating inspection (Q63). The pro version of this same check. During the snap itself, a system that cannot keep the house warm is an urgent call. Call (682) 438-8127 to ask about the soonest opening and what help is available.
What happens next
Do the mild-day list this week. If the test run exposes anything, book the inspection before the forecast turns. Mild-day bookings beat freeze-night queues.
Texas Heat & Air next step
Test run planned this week? If it exposes anything, call Texas Heat & Air at (682) 438-8127 before the forecast turns.
Related Questions
Why does my heater smell when I first turn it on?Is frost on my heat pump normal in winter?What should I do if the AC breaks during extreme heat?
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- https://www.energystar.gov/saveathome/heating-cooling/maintenance-checklist — supports pre-season heating checks and system preparation
- https://www.cpsc.gov/safety-education/safety-guides/carbon-monoxide/carbon-monoxide-fact-sheet — supports CO alarm testing and placement, and the generator/grill heating warnings