AC Running but Not Cooling? What to Check Before You Call

When the air conditioner is running but the house just will not cool down, it is usually one of a handful of problems. A few of them take two minutes to check yourself. Others need a technician with gauges and a meter. Here is how to tell which is which, so you do not pay for a service call you did not need, or wait on one you did.

Five checks that are safe to do yourself

• Thermostat. Make sure it is set to Cool, the temperature is set below the room temperature, and the fan is on Auto. Replace the batteries if the screen is dim or blank.
• Air filter. A clogged filter chokes airflow and is one of the most common reasons a system cools poorly or freezes up. If you cannot see light through it, replace it.
• Breaker. Check the breakers for the indoor unit and the outdoor unit. If one is tripped, reset it once. If it trips again, stop and call us. Repeated resets can damage equipment.
• Outdoor unit. Is the fan spinning? Is the unit buried in leaves, grass clippings, or a fence panel leaning on it? Clear the area around it, keeping at least two feet of open space. Do not remove the panels or spray the coil with a pressure washer.
• Vents. Make sure the supply vents are open and not blocked by furniture or rugs.

Signs to stop and call

• Ice on the indoor coil or on the refrigerant line. Turn the system off at the thermostat and let it thaw. Running it frozen can damage the compressor.
• The outdoor fan is not spinning, or the unit hums but does not start. This is often a failed capacitor or motor, which a technician can usually confirm and repair in one visit.
• Warm air from the vents with the outdoor unit running. This can point to low refrigerant from a leak, or a failing component. Refrigerant does not get used up, so low refrigerant means there is a leak somewhere.
• A burning smell, buzzing from the electrical panel, or water around the indoor unit. Turn the system off and call.

What a diagnostic visit looks like

We start with a flat-rate diagnostic, $89, so you know what the problem is before you commit to anything. We test the system, tell you what we found in plain language, and quote the repair price from our published price book. If you approve the repair, the $89 diagnostic is waived. No hourly meter running, and no line items you did not agree to.

Do you live outside Denton proper? We cover the towns around it, so check our service area page. Having no cooling at night or on a weekend? See our after-hours service page for how that works.

Need it looked at? Call 940-227-9916 or book online. Our prices are published so you know the number before we start.