LS Aircon Servicing Singapore

Aircon On and Off

7 Common Reasons Why Your Aircon Turns On and Off Frequently

Aircon on and off cycles, also known as short cycling, hamper the efficiency of your cooling system and lead to increased energy consumption. Your air conditioner, a silent guardian against the summer heat, may sometimes exhibit a perplexing behavior, frequently turning on and off. 

This comprehensive guide will elaborate on seven common reasons behind this phenomenon, offering insights and solutions to help you restore your aircon’s optimal performance and maintain a consistently serene indoor environment.

Why is My Aircon On and Off Frequently?

Before you fix the aircon on and off Iusse, it is important to explore the reasons behind the issue. As per LS Aircon Servicing Singapore, here are the seven most common reasons for aircon on and off issues.

1. Incorrect Thermostat Settings

The thermostat, like the conductor of an orchestra, orchestrates the cooling process. Any discord in its settings can result in erratic short cycling, disrupting the harmony of your indoor climate.

Check Thermostat Settings:

  • Start by verifying that the thermostat is set to the desired temperature.
  • Check the thermostat for any accumulated dust or debris that might interfere with its functionality.
  • Consider upgrading to a programmable thermostat for more accurate control over your cooling system.

Calibrate the Thermostat:

  • Perform a thermostat calibration to ensure accurate temperature readings.
  • If you’re uncertain about the calibration process, consult the user manual or hire professional assistance like LS Aircon Servicing.

2. Dirty or Clogged Air Filters

The unsung hero of your aircon system, the air filter, plays a pivotal role in maintaining optimal airflow. When neglected, these filters become a challenge, forcing the system to work harder and cycle more.

Regularly Replace Air Filters:

  • Stick to the manufacturer’s recommendations for replacing air filters.
  • Invest in high-efficiency filters to enhance cooling efficiency and indoor air quality.
  • Develop a monthly routine for checking and replacing filters, especially during peak usage seasons.

Clean Air Vents and Ducts:

  • Inspect air vents for any blockages or obstructions.
  • Schedule professional duct cleaning to remove accumulated dust and debris.
  • Ensure unobstructed airflow throughout your ventilation system.

Aircon On and Off Frequently

3. Refrigerant Issues

The magical substance responsible for cooling your indoor space, refrigerant, requires it to be at the right level for optimal performance. Imbalances can result in short cycling as the system struggles to maintain the desired temperature.

Inspect Refrigerant Levels:

  • Schedule regular professional maintenance to check refrigerant levels.
  • Resolve any leaks promptly to prevent further loss of refrigerant.
  • If necessary, seek the services of a certified technician, to recharge refrigerant levels.

Identify and Fix Leaks:

  • Conduct a thorough inspection for any visible refrigerant leaks.
  • Repair leaks immediately and consult a professional for complex leak detection procedures.
  • Seal all potential points of refrigerant escape to maintain system efficiency.

4. Thermostat Sensor Malfunction

The thermostat sensor acts as the eyes of your aircon, measuring the temperature around the evaporative coil. A malfunctioning sensor results in erroneous readings and subsequently causes frequent cycling.

Check Thermostat Sensor:

  • Ensure the sensor is positioned close to the evaporative coil but does not touch it.
  • Gently adjust the sensor’s position if needed to increase its accuracy.
  • Replace the sensor if it is damaged or consistently providing inaccurate readings.

Inspect Wiring Connections:

  • Check the wiring connections associated with the thermostat sensor.
  • Tighten any loose connections and replace damaged wires to maintain proper functionality.

5. Electrical Issues

Within the mix of wires and components, your aircon relies on a stable electrical connection. Faulty wiring or malfunctioning components can disrupt the cooling cycle.

Inspect Wiring and Components:

  • Schedule a professional inspection of the electrical components.
  • Look for signs of frayed or damaged wiring and resolve them promptly.
  • Rely on certified technicians for any required electrical repairs to ensure safety.

Check Capacitors:

  • Inspect the start and run capacitors for signs of wear or damage.
  • If you notice any abnormalities, such as bulging or leakage, consult a professional for capacitor replacement.

My Aircon On and Off Frequently

6. Oversized or Undersized System

Your aircon must be just the right size for your space. An oversized unit cools too quickly, leading to frequent cycling, while an undersized one struggles to maintain the desired temperature.

Consult with a Professional:

  • Engage a professional HVAC technician to assess your home’s cooling requirements.
  • Consider upgrading to a properly sized aircon if your current unit is mismatched to your space.
  • Ensure your home is adequately insulated and windows and doors are properly sealed to optimize efficiency.

7. Dirty or Blocked Evaporator or Condenser Coils

The intricate transmission of heat exchange between the evaporator and condenser coils can be disrupted by accumulated dirt and debris. This causes the system to overheat and cycle more frequently.

Regular Coil Cleaning:

  • Schedule regular professional maintenance to clean the evaporator and condenser coils.
  • Keep the area around outdoor units clear of debris, allowing for unobstructed airflow.
  • Trim vegetation around the outdoor unit to avoid blockages and maintain optimal performance.

Invest in Protective Measures:

  • Consider installing coil guards or protective barriers to prevent debris buildup on the coils.
  • Periodically inspect these protective measures and adjust them as needed.


As the guardian of your indoor comfort, your aircon deserves meticulous care and attention. If you notice your aircon on and off cycles, you need to find the reasons for that promptly. The culprit might lie in one of the common issues explained in this article. By addressing these concerns promptly, you can restore the efficiency of your cooling system and contribute to energy conservation and lower utility bills. 

Don’t let the mystery of your air conditioner’s behavior persist. Resolve the issue by taking proactive steps to diagnose and resolve it. This approach ensures your cooling system provides the cool, consistent comfort your home deserves. With a well-maintained air conditioner, you can beat the heat and enjoy comfort and serenity.