Central AC Stopped Working? Here's What Every Fort Worth Homeowner Should Do First

The thermostat is your AC's control center. If something is off there, the rest of the system won't respond — no matter how well everything else is working. This is the first place to check, and it takes less than two minutes.

Confirm the thermostat is set to "cool" and that the target temperature is below your current indoor reading. If the screen is dim or completely blank, replace the batteries before assuming a system failure. Dead batteries are one of the most common reasons an AC appears to stop working entirely.

Also check that no one accidentally switched the system to "heat," "fan only," or a hold or vacation mode. It happens more often than most homeowners expect — particularly after a filter change or at the start of cooling season. Smart thermostats are worth checking through the app as well. Some lose their Wi-Fi connection and default to a hold setting that overrides your normal schedule.

Our Fort Worth technicians regularly arrive at homes where the thermostat was switched to "fan only" during a filter change. The fan runs, air moves through the vents, but no cooling happens. A two-minute check at the thermostat saves a service call.

Thermostat Check — In Order:

1. Set to "cool" mode — not "heat," "fan only," or "off"
2. Target temperature set at least 5 degrees below current indoor reading
3. Screen dim or blank — replace batteries first
4. Check for accidental hold, vacation, or away mode
5. Smart thermostat — open the app and confirm settings and connectivity

If the thermostat looks right but the system still won't run, the next place to check is your electrical panel. A tripped breaker cuts power to the AC completely — and it can happen without any obvious warning inside the house.

Central AC systems typically use two separate breakers: one for the indoor air handler and one for the outdoor condenser unit. Both need to be in the ON position for the system to run. A tripped breaker won't always look fully off — it often sits in a middle position between ON and OFF. Look carefully at each breaker before assuming everything is fine.

To reset a tripped breaker, flip it firmly to OFF first, then back to ON. Then go check whether the system starts. If the breaker trips again immediately after you reset it, stop — do not reset it a second time. A breaker that trips twice in a row is signaling a problem inside the system. Resetting it again can cause more damage. That's a technician call.

In Fort Worth's older Westside neighborhoods, aging electrical panels sometimes have AC breakers that are undersized for the system running on them. A breaker that keeps tripping isn't a nuisance — it's a signal worth taking seriously. Also check the outdoor disconnect switch, a covered box mounted on the exterior wall near the condenser unit, and confirm the handle is seated properly.

A clogged air filter is one of the most common reasons a central AC shuts down — and one of the easiest to miss. When the filter gets severely blocked, airflow through the system drops to the point where the evaporator coil freezes and the system shuts off entirely. It happens more often than most homeowners realize.

Pull the filter out and hold it up to a light source. If you can't see light passing through it, replace it. Most filters should be replaced every one to three months depending on your household — more often if you have pets or anyone with allergies. Replacing a filter takes five minutes and costs a few dollars. A frozen evaporator coil takes much longer to address.

After checking the filter, walk through every room. Confirm that all supply vents — the ones that blow air out — and return vents — the ones that pull air in — are fully open and unobstructed. In Fort Worth's ranch-style homes, return vents are often positioned near baseboards in hallways. They're easy to block with furniture during a room refresh and just as easy to overlook during a walkthrough.

Closing vents in unused rooms is a habit that works against the system. It increases pressure inside the ductwork, forces the AC to work harder, and can trigger shutdowns. Leave all vents open, even in rooms no one is using.

Airflow Quick Check:

• Pull the air filter — replace if light won't pass through it
• Check all supply vents — open and unblocked
• Check all return vents — clear of rugs, furniture, and drapes
• Do not close vents in unused rooms
• Confirm the filter is seated correctly in its slot after replacement

The outdoor condenser unit does half the work of cooling your home — but it's the half most homeowners never think to check when something goes wrong. A five-minute visual inspection outside can tell you a lot about what's happening with your system.

Start with the disconnect switch. It's a small covered box mounted on the exterior wall of your home, usually within a few feet of the condenser unit. Open the cover and confirm the handle is seated firmly in the socket. It can get bumped loose during yard work, a pressure wash, or after a storm. If the handle is pulled out or sitting loose, that's likely why the system isn't running.

Next, look at the condenser unit itself. Check for leaves, grass clippings, branches, or other debris sitting on top of or packed around the unit. Fort Worth's spring storm season — particularly around the Cultural District and Near Southside — regularly pushes cottonwood, leaves, and storm debris directly into condensers. A quick check after any significant weather event takes two minutes and can prevent a service call. Light surface debris on the exterior coils can be rinsed gently with a garden hose. Do not use high pressure and do not soak the unit.

If you see ice on the coils or on the refrigerant lines running into the house, stop. Turn the system off at the thermostat and do not try to remove the ice manually. Ice buildup means the system isn't moving air correctly or refrigerant levels have dropped. Running it further damages the compressor — the most expensive component in the system.

Do not remove any panels from the outdoor unit or attempt to access internal components. Electrical and refrigerant issues inside the condenser require a licensed technician.

Working through a checklist when it's 104°F outside is nobody's idea of an easy afternoon. If the steps above didn't get your system running — or if something you saw along the way put you in the "call now" category — our Fort Worth technicians are ready to help.

Berkeys Plumbing, A/C & Electrical is bringing 50 years of expertise to Fort Worth homeowners. Our team holds a 4.8-star rating across 161+ reviews, and we're available for same-day AC diagnosis and repair. Whether your system won't turn on, tripped a breaker, or stopped cooling without any obvious reason, our technicians arrive with the diagnostic equipment to find the problem fast.

Our customer service team is available 24 hours a day, 7 days a week. Actual service appointments run 8am–6pm daily.

Berkeys Plumbing, A/C & Electrical — Fort Worth Business Address: 3001 W 5th St Suite 700, Fort Worth, TX 76107 Call (817) 799-6090