HVAC | October 1, 2023

AC Not Blowing Cold Air: 10 Possible Reasons This Happens

When your air conditioning system runs, you expect to feel cool air coming from the vents. If you feel warm air (or nothing at all), you may think, “Why isn’t my central air blowing cold air?” Some issues require air conditioning repair, while others may call for replacement. While you wait for emergency air conditioning repair service, you can check on these 10 possible causes.

1. Low Refrigerant

If you wonder, “What makes AC cold?” refrigerant is the answer. Air conditioning systems require refrigerant to extract heat from the indoor air. The closed refrigerant line keeps the system running through its lifespan, but refrigerant leaks can lead to a low charge. You can spot a leak by looking for dripping or listening for hissing sounds. Because refrigerant contains toxic chemicals, you should call our technicians for prompt repair service.

2. Clogged Air Filter

Air filters remove debris and other contaminants from the fresh, outdoor air before circulating it through the system. Dirty air filters force the system to work harder to create sufficient air flow, which can lower efficiency and performance. Clogged filters can compromise the internal components of the system, as well. If you notice that your air conditioning is not blowing cold air, checking and replacing the air filter could provide a simple solution.

3. Frozen or Dirty Evaporator Coil

The evaporator coil sits inside the interior part of your air conditioning system, cycling refrigerant through the coil to absorb heat and humidity. If the evaporator coil gets dirty, it may stop working effectively. Excessive dirt and debris can lead to a frozen coil, which can cause the system to start shutting off too quickly, cycle room-temperature air, or break down.

4. Blocked Condenser Coil

The condenser coil helps to release heat from the refrigerant so the cooling process can begin again. When these coils get dirty, they make it harder for the system to eliminate the heat. You may notice that the system continues to operate, but cooling efficacy starts to drop. You can brush off the coils to clear them of grass clippings, dirt, and other debris.

5. Closed or Blocked Registers

When you consider what to check when your AC is not cooling, you may want to take a look at the registers in each room. Closed or blocked registers will provide little air flow. You may observe that one room feels much warmer than the others. If the register appears completely open, you may have a blockage somewhere in the ductwork.

6. Incorrect Thermostat Settings

In order to provide cooling, your thermostat must operate at an “auto” or “cool” setting. If you notice that your thermostat setting shows “fan” or “heat,” you should change it and see if it solves the problem. Thermostat settings that seem correct — but do not provide cooling at the right time — may indicate a problem with the sensor or the thermostat’s connection to the system.

7. Clogged Condensate Drain Line

Your air conditioning system releases humidity from the indoor air through a condensate drain line that leads out of your home. Like any other pipe, this drain line can accumulate dirt, algae, or ice. If your drain line has a significant blockage, the condensation will back up into the system. A clogged condensate drain line can lead to short cycling or a complete shutdown of the system.

8. Tripping Circuit Breaker

A sudden surge of power can trip the circuit breaker or blow a fuse, which can cause the air conditioning system to fail. Power issues create the most likely scenario for your air conditioner not turning on. If you notice that the circuit breaker needs resetting, you can reset it and try to turn on the system again. Regular tripping may indicate other problems in the system, such as dirty air filters, faulty connections, or a failing capacitor.

9. Improper Sizing

When you buy a new air conditioner or furnace, you need to choose an HVAC system in the right size for your home. Undersized air conditioning systems often fail to keep up with the cooling load, which can lead to poor performance, low efficiency, and wear and tear on the system. If your existing system cannot meet your needs, even after replacing the unit, you may want to consider ductless mini split installation service for zoned cooling and higher efficiency.

10. Leaky Ductwork

When you have air blowing out of vents but not cooling the house, you need to find out where the air goes. Leaks in the ductwork can lead to conditioned air escaping before it reaches certain rooms. This conditioned air may make some rooms feel colder, while others feel uncomfortably warm. Fixing ductwork leaks can help to improve performance and efficiency.

Schedule Maintenance to Minimize Air Conditioning Problems

If you want to minimize your risk for these air conditioning problems, you should schedule annual HVAC maintenance. Air conditioning maintenance helps you to keep your system clean and working well, which can increase efficiency and reduce the chances of an unexpected breakdown.

Call ARS/Rescue Rooter for Expert Repair

When you start asking, “Why my AC is blowing cool air but not cold?” you need the experts at ARS/Rescue Rooter to help. Contact us to learn more about our services, book an appointment, or find the nearest ARS/Rescue Rooter location.