As the summer temperatures soar and the humidity increases, the last thing you want is your air conditioner system to stop cooling. When this happens frustration and panic can set in as you try to figure out why. Fear not! We have compiled a list of the most common issues that can stop an air conditioner from cooling. We also advise if you can troubleshoot yourself or if it's time to call an HVAC professional.Thermostat ProblemsNine times out of 10, the reason an air conditioner isn’t cooling properly is because of thermostat problems. One obvious thing to check is the thermostat mode. Is the thermostat on and set to cool? You should also look at the temperature. Is it set cooler than the current indoor temperature? If not lower the setting and see if it kicks the unit on. Does your thermostat run on batteries? Do they need to be replaced? Do you have a Google Nest or other smart sensor? Have you accidentally left the program in vacation mode? Lots of things can go wrong with a thermostat, so it is always advised to check this first.Dusty FiltersYour air conditioning unit has a filter that needs to be regularly replaced. If the filter becomes dirty, it reduces the airflow and eventually stops your air conditioning from working. Locate your air filter, turn off your system, and check to see how dirty the filter looks. Replace if necessary.Dirty or Blocked Air Conditioner Compressor UnitYour Carrier or Bryant compressor unit can become dirty too, particularly as it is outdoors. Locate the unit and clear away any obvious debris like leaves and sticks. If the unit looks dirty you can vacuum off the dust or remove it with a gentle hose spray. Also check that there are no trees, fences, or other structures within 2 feet.Air Conditioner Refrigerant LeakIce buildup on the copper lines or evaporator coils of your indoor unit could mean you have a refrigerant leak. When refrigerant levels become too low the coils absorb heat, condensation builds up, and the lines freeze. If you suspect a refrigerant leak, always call an HVAC professional to do the repair. Refrigerants are dangerous and by law require a licensed professional to handle.Need Professional Advice?Air conditioner units are complex systems. So even if you think you have identified the problem there may be other issues causing your air conditioning not to cool. To get an accurate assessment of the problem, it is always advised to contact an HVAC professional. Air Conditioning Southeast can help you find a trusted HVAC specialist near you. Contact us today.