AC Not Working in Houston? Here’s What to Check Before Calling the Pros

When your air conditioner in Houston, TX suddenly stops working in the middle of a sweltering Houston summer, it’s easy to assume the worst.

But before you pick up the phone, there are a few things you can check that might save you time, money, and the discomfort of sitting in a hot house.

The team at Luke’s Plumbing & Air Conditioning created this step-by-step checklist to help Houston homeowners troubleshoot common AC issues before scheduling professional AC repair in Houston, TX.

Some of these fixes are easier than you think—and could get your cool air flowing again in minutes!

1. Start with the Thermostat

Sometimes, the AC itself isn’t the problem—the thermostat is.

Check that it’s set to “Cool,” not just “Fan.” Make sure the set temperature is lower than the current room temp. If your thermostat runs on batteries, try replacing them. Power outages or power surges may also reset your thermostat’s settings, especially if it’s programmable.

If the display is blank or flickering, or if changing the settings doesn’t do anything, your thermostat might need recalibration or replacement. At that point, it’s worth having a technician evaluate it during an AC service appointment.

2. Check the Breaker Panel

Air conditioners use a lot of electricity, especially when working hard in the Houston heat. If your system suddenly shuts down, a tripped breaker could be the culprit.

Find your breaker panel (typically in the garage or utility room). Look for labels like HVAC, Furnace, or A/C. If a breaker is flipped to the middle or “Off” position, turn it fully off, then back on.

If the breaker trips again after a reset, stop there. This could indicate a wiring problem or failing component, and it’s safest to call for professional air conditioning repair in Houston.

3. Replace Your Air Filter

A clogged filter is one of the most common and overlooked reasons for poor airflow and system shutdowns.

To check it, remove the filter and hold it up to the light. If you can’t see through it, it’s too dirty. Replace it with a new one—ideally every 30 to 90 days depending on usage, pets, and indoor air quality.

Many airflow issues (including coil freezing and overheating) can be prevented with this one simple maintenance step. Regular filter checks are also a key part of AC maintenance in Houston.

4. Inspect the Outdoor Unit

Your AC’s outdoor condenser plays a major role in the cooling process. If it’s covered in leaves, dirt, or yard debris, it won’t be able to release heat effectively.

Clear at least two feet of space around the unit. Gently rinse the coils with a garden hose to remove dirt and buildup. Never use a pressure washer, and don’t open the unit unless you’re licensed to do so.

Seasonal cleanups like this are part of our comprehensive HVAC services in Houston, TX.

5. Make Sure Vents Are Open and Unblocked

Take a walk around your home. Are any vents closed or partially blocked by furniture, rugs, or curtains?

Closed vents create pressure imbalances in the system, which can cause airflow problems and temperature inconsistencies. Open all supply and return vents—even in unused rooms—and vacuum away visible dust. Balanced airflow helps your AC cool the home more efficiently.

6. Look for Ice on the System

If your indoor unit or refrigerant lines are covered in frost, that’s a sign something’s off. Frozen evaporator coils can stop your AC from working altogether and may lead to long-term damage.

Turn the system off and switch the fan to ON. This will help thaw the coils. After a few hours, turn the system back to cool and observe what happens. If the ice returns, there’s likely a deeper issue such as low refrigerant, dirty coils, or airflow problems. Schedule AC repair to prevent further damage.

7. Move Heat-Producing Items Away from the Thermostat

It sounds simple, but many homeowners unknowingly place lamps, TVs, or computers near the thermostat. These items produce heat and can trick the thermostat into thinking the room is warmer than it actually is.

Move electronics and lamps away so the thermostat gets an accurate reading of your space. This helps ensure your AC cycles on and off properly.

8. Still Not Working? Call the Experts

If none of the above steps restore your cooling, or if your system is blowing warm air, making strange noises, or turning on and off constantly, it’s time to bring in a professional.

The licensed technicians at Luke’s Plumbing & Air Conditioning can quickly diagnose and fix:

• Refrigerant leaks
• Frozen or dirty coils
• Electrical issues
• Broken capacitors and motors
• Malfunctioning thermostats
• Worn-out compressors

If your system is more than 10 to 15 years old or needs constant repairs, we can also help you explore your options for AC replacement in Houston, TX. We’ll walk you through the process and recommend the best system for your home, budget, and cooling needs.

For Houston homeowners looking to cool a single room, garage, or addition, we also offer energy-efficient ductless cooling systems.

Your Go-To Team for AC Services in Houston, TX

Whether your air conditioner needs a minor fix or a major overhaul, Luke’s Plumbing & Air Conditioning is here to help. Our team provides expert AC services in Houston, including fast repairs, preventive maintenance, and full system installations.

We show up on time, explain what’s happening in plain language, and treat your home with care.

Contact us today to schedule an appointment and get your home back to cool, comfortable, and stress-free.

Call (713) 686-7000