Common Reasons Why Your AC Won’t Turn Off

Does it seem like your cooling system never stops cycling lately? You need to pinpoint why your AC won’t turn off to determine whether it’s just the hot weather or if a deeper issue lurks beneath. Long cycling is a common warning of potential energy drains and signal disconnections. 

A1 Mechanical Heating & Cooling’s crew has seen all kinds of issues during AC repair in Louisville, KY, and can provide you with more information regarding the reasons behind air conditioners cycling endlessly. Find out the most common reasons and what to do about them below.

When Are Long Cycles Normal?

It can take a while to notice the AC running continuously. After all, a well-maintained unit makes little more than background noise that you can easily ignore. Plus, it might run more often when summer temperatures spike, which is normal and helps you stay comfortable. 

You might also prefer cooler than normal temperatures and set your thermostat to a low setting, which can force your air conditioner to work overtime without doing anything wrong. However, cycles lasting more than 20 minutes and occurring more frequently than three times per hour mean your air conditioner is probably struggling.

How Come Your AC Won’t Turn Off?

Many of the most common AC problems can cause erratic cycling. The cooling cycles might happen in short, sporadic bursts or prolonged, continuous operations. We’re going to explore long-cycling specifically. 

Long-cycling means your HVAC system is working much too hard to achieve the temperature setting on your thermostat. When your AC won’t turn off, you might have one of the issues listed below on your hands. 

Uncalibrated Thermostat

You might not expect a thermostat malfunction, especially if your device worked perfectly until now. However, thermostats need calibration for accurate temperature measurements, to send signals, and to initiate cycle starts or stops.

First, check the settings to see if you accidentally set the device to “Fan.” If you discover that the switch indicates “Fan,” push it to the “Auto” slot. The “Fan” setting allows the motor fan to constantly cycle regardless of the cooling needs. This should stop the fan and, therefore, the cycle.

If that doesn’t work, then a calibration service might. Thermostats house delicate temperature sensors that become coated in dust and lose accuracy over time. The device may detect a higher temperature due to faulty sensors insulated by dust. That reading may not reflect your actual indoor temperature. 

Frozen Coils

The evaporator coil changes the refrigerant from liquid to gas by taking heat out of the refrigerant. Then, the refrigerant can move through your system, absorb more heat, and keep your building cooler. This coil also removes moisture from the air passing through the unit, lowering indoor humidity. 

Sometimes, the evaporator coil gets dirty and fails to absorb enough heat, resulting in a frozen evaporator coil. It still removes moisture, but the moisture freezes instead of liquifying. If your AC won’t turn off, it might be because of insufficient heat removal from the icy coil.

Low Refrigerant Level

Air conditioners use refrigerant to absorb and deposit heat away from your rooms. Sometimes, the refrigerant lines spring a leak. Wear and tear or a puncture from an unseen event can lower your refrigerant levels.

When refrigerant hits the air, it becomes a gas, so you aren’t likely to see streams of the substance flowing out of your unit. However, low levels won’t soak up enough heat to lower the indoor temperature, and your air conditioner will run non-stop.

Slow Fan Speeds

The blower fan pushes air provided by the return register back into circulation. It is responsible for that fresh burst of cool air flowing from your vents. Like ceiling and box fans, this component can become coated in dust, especially on the fan blades. 

Dust, grime, and other buildup eventually weigh down the blades, preventing them from circulating as quickly. Because of this, your air conditioner will take longer to reach your preferred thermostat setting. 

Poor Unit Sizing

Unit size is more important than many property owners realize. Even small aberrations from the recommended British Thermal Unit requirement can cause disastrous problems. In this case, an undersized air conditioner will cycle for too long because it can’t keep up with the temperature demands of a big building. 

The only way around this problem involves removing the old, undersized air conditioning and replacing it with a properly sized one. Make sure to work with a reputable HVAC company, like A1 Mechanical Heating & Cooling, to avoid future mix-ups.

Airflow Restrictions

Finally, restricted airflow can keep your temperature higher than your settings while forcing your system to work overtime. These restrictions can manifest in several ways:

• Dirty air filter: The reason your AC won’t turn off might be as simple as a dirty filter. Change it to see whether the fresh filter remedies the issue. 
• Blocked vents: Check your duct openings for furniture and other obstacles that might keep them from distributing air throughout the building. 
• Filthy ductwork: Schedule duct cleanings every three to five years. This service has additional benefits, like better indoor air quality and higher HVAC efficiency. 
• Overwhelmed outdoor unit: The outdoor equipment weathers lawn mowing, leaves blowing, and twigs or branches dropping from trees. Clean its fins and grates to protect its ability to function. 
• Crowded indoor unit: The air handler in your building can also perform poorly if it has no room to breathe. Maintain a clearance margin for two feet on all sides.

While these actions won’t solve all HVAC issues, they can create a foundation for your equipment to function and move air easily. If you can’t solve the long cycles on your own, you know who to call.

A1 Mechanical Heating & Cooling: Your Trusted Company for AC Repair in Louisville, KY

A1 Mechanical Heating & Cooling’s expert technicians have no problem finding the reason why your AC won’t turn off. If you’re ready for a thorough AC repair in Louisville, KY, call (502) 708-2247 to avoid DIY repairs and protect your comfort.