It is frustrating when you're trying to cool off in the midst of Singapore heat, but suddenly your air conditioner turns off abruptly, only to restart back up again. An air conditioner turning on and off in a single cooling cycle is short cycling, which can be caused by several reasons.
Short cycling is a common aircon issue in Singapore, where constant use due to the hot weather can eventually lead to wear and tear. It’s important to address the short-cycling issue immediately because if it keeps happening, it can cause long-term damage and higher energy bills.
What Is Short Cycling?
Short cycling is when an air conditioner turns on and off too frequently without completing a full cooling cycle. Instead of running steadily to reach and maintain the desired temperature, the AC shuts off prematurely and restarts shortly after. This issue is quite common in hot and humid regions like Singapore, where air conditioners work harder to maintain indoor comfort.
You might not be sure that your AC is short cycling, but the clearest sign that your AC is short cycling is if it turns off within a few minutes of starting and then restarts again a short time later. Typically, an air conditioner should run for around 10–15 minutes per cycle. If you notice that your AC stops and starts too often, it’s a sign that something may be wrong.
The short cycling issue in AC should be addressed immediately, because if it is left for too long it can lead to several issues, such as:
- Higher electricity bills because the AC constantly turns on and off, and it consumes more energy than necessary.
- Faulty compressors because frequent cycling puts extra strain on the compressor, and this can shorten the lifespan of the unit.
- AC might have poor cooling performance because it doesn’t run long enough to distribute cool air evenly.
If you suspect that your AC has a short-cycling issue, it’s best to immediately seek professional help to address the issue.
What Causes AC Short Cycling?
Reason #1 Oversized Air Conditioner
There is a common misconception about air conditioners. The larger and more powerful the unit does not mean a more efficient cooling cycle as most people assume. An oversized unit causes air conditioner short cycling issues as the unit cools the room quickly, shutting down when the room has been cooled to the set temperature on the thermostat.
In this case, it is a better idea to size down rather than fix your air conditioner since there are no broken or faulty parts. The issue is with the size of the unit, so it is best to replace the unit with one of a more appropriate cooling capacity or place the large unit in a bigger room to cool a larger area properly.
Reason #2 Clogged Air Filter
A dirty air filter restricts the airflow in the air conditioner, which can cause the unit to freeze up or overheat. When the air conditioner freezes or overheats, it can lead to short cycling issues. A deep clean of the air filter should fix the issue.
Reason #3 Refrigerant Leaks/Low Refrigerant Levels
Your AC unit runs on refrigerant - a coolant that turns warm air into cool air during a full cooling cycle. Short cycling happens when the AC unit is short of refrigerant due to a leak, where the AC system cannot properly function without the coolant. You will need to have a Luce Aircon professional HVAC technician top up the refrigerant and fix the leak.
Reason #4 Frozen Evaporator Coil
A frozen evaporator coil traps the cold air within the unit, and the air conditioning system cannot remove the warm air from your room. The result is a short cycle as the air conditioner malfunctions. Frozen evaporator coils are often caused by a layer of dust and debris that covers the coils, so keep these coils clean with a can of compressed air for good measure.
Reason #5 Faulty Thermostat
Sometimes, the issue isn't with the air conditioning unit, but with the thermostat! A faulty thermostat may be reading the room temperature incorrectly, causing short cycling. Always check the batteries of your thermostat, and replace batteries as needed.
How to Fix Short Cycling Air Conditioner?
If you suspect your AC is having a short cycling issue, here’s what you can do to try to fix it.
- Check and Replace the Air Filter: A clogged filter can restrict airflow, causing the AC to overwork and short cycle. In Singapore’s dusty environment, filters should be cleaned or replaced every month.
- Ensure the Thermostat Is Working Properly: A faulty or poorly placed thermostat can misread room temperatures and cause the AC to turn off too soon. Keep it away from direct sunlight or heat sources.
- Inspect the Refrigerant Levels: Low refrigerant levels can cause the compressor to overheat and shut down.
- Check the AC Size: If the unit is too powerful for the space, it will cool too quickly and turn off before completing a full cycle.
- Schedule Regular Maintenance: Regular servicing by a professional can prevent issues like short cycling and ensure your AC runs efficiently. Given Singapore’s year-round heat, it’s best to have aircon maintenance done by our technician at Luce once every 6 months.
Important! If short cycling persists, contact an aircon servicing company to diagnose and resolve the issue before it leads to costly repairs.
4 Tips to Prevent Short Cycling Problems
Tip #1 Install a Suitably-sized Air Conditioner
Bigger isn't always better, and that's certainly true for air conditioners. Go for an appropriately sized air conditioner for your room instead of a larger one, and you should prevent the AC from short-cycling. Our Luce Aircon technicians can gladly assist you in choosing a brand and model that fits your room.
Tip #2 Clean Your Air Filters Regularly
Clean your air filters once every month for the best care. Doing so will prevent dust buildup, and allow for proper air circulation around your air conditioning unit, which will prevent the unit from short cycling.
Tip #3 Have an Air Conditioner Maintenance Routine
Have your air conditioning system checked regularly for proper maintenance. Our professional technicians here at Luce Aircon are well-versed in their craft, and they can help you maintain the good condition of your unit with an annual checkup! With a maintenance routine, you'll catch issues with your air conditioning unit before they turn into short cycling problems.
Tip #4 Have Your Air Conditioner Cleaned
Besides cleaning your air filter, have your AC system professionally cleaned twice a year to prevent short cycling. Our professional cleaning services will get your AC clean without damaging the unit, so you can enjoy the cool air it provides longer. Only an HVAC professional can properly clean the internal parts of the unit, so leave the cleaning to us!
Maintain Your AC
Proper maintenance is key to avoiding short cycling, as regular servicing ensures your aircon stays efficient and lasts longer.
Keep your aircon in top shape with Luce, the leading air conditioning cleaning and repair company in Singapore. We provide you with quality cleaning services that will ensure every part of your AC is deep cleaned the right way.
Contact us today to learn more about our services and book an appointment!
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