A fall HVAC checklist for DFW homeowners: what a Texas summer did to your AC, when to test the heat, and the timeline that avoids a January emergency call.
September in North Texas is the only stretch of the year when your HVAC system isn’t under pressure. The AC has survived another summer and the furnace hasn’t been asked for anything since February. That gap is the cheapest window on the calendar to find a problem, because everything found in it is a scheduled repair instead of an emergency one.
Before the cooling season ends, it’s worth confirming the system came through it intact — problems that show up now are problems you don’t inherit next May.
Pick a mild day and run the heat for twenty minutes. This is the single highest-value item on the list. A furnace that’s going to fail this winter almost always fails on its first real run, and in North Texas that first real run happens on the same night as everyone else’s — when every HVAC company in the metroplex is booked solid.
You’re listening for: heat that actually arrives, no burning smell past the first few minutes, no cycling on and off within a minute or two, and no error code on the board.
Filters get changed less often than anyone admits, and a summer of running the blower for four months is exactly when it goes from dirty to restrictive. A clogged filter starves airflow, which freezes evaporator coils in the summer and overheats heat exchangers in the winter. Both of those are expensive; the filter is not.
A 1-inch filter in a DFW home with pets realistically needs replacing every 30–60 days. A 4- or 5-inch media filter runs six months to a year.
Free, takes a minute, and most people never do it. Counterclockwise in summer pushes air down; clockwise on low in winter pulls cool air up and pushes the warm air pooled at the ceiling back down the walls. In a room with high ceilings it’s a genuine comfort difference at zero running cost.
North Texas homes lose more energy to leaks than to equipment inefficiency. The highest-return targets are the ones you can reach without a contractor: weatherstripping on exterior doors, caulk around window frames, and the attic hatch, which is frequently the single largest uninsulated opening in the house.
Duct leakage is the bigger prize and the one that needs help — a typical DFW attic duct system loses 20–30% of the air it carries before it reaches a room.
| When | Do This |
|---|---|
| September | Clear the drain, clean the outdoor coil, change the filter |
| Early October | Run the heat for 20 minutes on a mild day |
| Late October | Book the heating tune-up — before the first freeze warning |
| November | Weatherstripping, attic hatch, ceiling fans reversed |
| Any time | Test the CO detectors if you have gas heat |
Everything above is a homeowner job except the parts that need instruments: combustion analysis, heat exchanger inspection, refrigerant charge, and static pressure. Those need a technician, and October is when they’re available. In January they’re not.
Book a heating tune-up at 214-900-2533, or see our HVAC maintenance service. Our Comfort Club covers both seasonal visits and puts you ahead of the queue when it does get cold.
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Kenny founded Absolute Comfort Mechanical after more than 20 years in the Dallas–Fort Worth HVAC trade, because he was tired of watching homeowners get sold equipment they didn't need. He still runs diagnostics himself and reviews the technical advice published on this site.
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