AC Not Cooling? Five Things to Check Before You Call Anyone

Your air conditioner is running, but the house is not getting cold. Before you pay for a service call, five quick checks will tell you whether this is something you can fix yourself in the next ten minutes. The Rise crew walks through all five on a real system here.

1. Thermostat mode and batteries

Make sure the thermostat is set to Cool, not Heat or Fan, and the set temperature is below the room temperature. If the screen is blank or dim, replace the batteries. A surprising number of “broken” air conditioners are a thermostat that quietly switched to Fan or lost power.

2. Both breakers

Your system has two: one for the indoor air handler or furnace, and one for the outdoor condenser, often in a small box on the wall next to the unit. A breaker that looks on but sits slightly off-center has tripped. Flip it fully off, then on. If it trips again, stop. That is an electrical fault and a job for a technician.

3. The air filter

Pull the filter. If you cannot see light through it, replace it. A clogged filter chokes airflow across the indoor coil, the coil ices over, and the system blows warm air or nothing at all. If you suspect the coil has frozen, turn the system off and leave the fan on for a few hours before trying again. We go deeper on this in why your AC is blowing warm air.

4. Is the outdoor unit actually running?

Go outside. The fan on top of the condenser should be spinning and you should feel warm air coming off it. If the unit is silent, or humming without the fan turning, it is not cooling, and the cause is usually a failed capacitor, a contactor or a tripped breaker. Turn the system off at the thermostat so the compressor is not trying to start against a fault.

5. Closed or blocked supply vents

Walk the house and open every supply register. Closing vents in unused rooms does not save energy on a central system; it raises pressure in the ducts and starves the rest of the house. Move furniture and rugs off floor registers while you are at it.

If all five check out

Then the problem is inside the system: refrigerant charge, a failing compressor, a bad motor, or a control issue. That needs gauges on the system and readings taken, which is not a do-it-yourself job. The good news is you have already ruled out the simple causes, so the technician can start where it matters. Book an AC repair visit and tell us what you found.

Keep it from happening again

Three of the five items above are maintenance. A seasonal AC tune-up catches weak capacitors, dirty coils and clogged filters before July does, and our Rise VIP plan builds that in twice a year. If the system has a refrigerant problem, read why low refrigerant means a leak before anyone tops it off.

Quick questions

The unit is running but the air is only slightly cool. Is that the same problem? Often it is a dirty filter or coil, or a system that is low on refrigerant. Run the five checks, then call if it does not improve.

Do you come out the same day? We do our best, especially in summer. We are based in Seguin and serve New Braunfels, Kyle, San Marcos and the towns within about 50 miles. See every town we serve.