Singapore’s humid climate can sometimes cause frozen aircon lines, especially when the unit is overworked or improperly maintained. Frozen AC lines indicate issues that could shorten the lifespan of your unit if left unaddressed.
In this article, we take a look at the 5 most common causes for a frozen AC line, and how you can troubleshoot them. We'll also provide helpful tips to prevent an AC line from freezing and to keep your air conditioning unit in good working condition for longer.
Why is My Air Conditioner Lines Freezing Up?
There are multiple reasons why your AC line is frozen. Anything from dirty filters to refrigerant leaks can cause a frozen AC line. Not all reasons can be easily fixed at home, and you may need an air conditioning repair service to tackle chemical coolant leaks, and the malfunctioning of internal parts.
#1 Blocked Vents
First, check the supply vents. Are there obstructions blocking the supply vents, causing the cooled air to circulate inside the unit, or are there obstructions making it difficult for the cold air to travel through the room? Obstructions, such as furniture, fixtures, and walls, blocking the airflow from the vents are some of the common reasons why your AC line is frozen.
To troubleshoot, power your AC system off. Check all the vents in both the indoor and outdoor units to see if fixtures or debris are blocking the supply vents, and remove these obstructions. Let the frozen AC line thaw out before powering the AC system back on, then see if this solves the problem with your air conditioner line.
#2 Dirty Air Filter and Coils
You may notice your AC unit blowing warm air instead of cool air due to a dirty air filter. Besides blocked vents, one of the most common causes of frozen AC lines amongst our clients in Singapore is dust accumulation in filters and coils.
Troubleshooting this problem is fairly simple. Power your AC unit off, then let the frozen AC line thaw. You may use a hair dryer to apply warm air to thaw the ice buildup faster, but this is not necessary. Remove the air filter carefully and wash it with a combination of soap and water. Vacuum up the dust surrounding the evaporator coils.
#3 Refrigerant Leak
A refrigerant leak is another cause for a frozen air conditioner, however, this issue cannot be easily solved at home. Refrigerant cools the air that goes through the air conditioning unit, and when the chemical coolant leaks out, it can freeze up the water accumulation around the evaporator coils.
Refrigerant leaks cannot be solved at home without proper tools. The coolant can be irritating to the skin and lungs, so it is best to have a professional find and fix the leak. A professional HVAC technician will use a colored dye to locate the leak, fix it, and top up your refrigerant to keep your air conditioner in good condition.
#4 Cold Air
If the weather is cold outside, it can cause your air conditioner to freeze. An air conditioner freezes when there is enough humidity inside the unit, coupled with freezing-low temperatures outside. When this happens, your AC unit may blow warm air instead of cooled air, and you may notice ice accumulation around the evaporator coil.
To troubleshoot this, shut down your air conditioner, and check the frozen AC lines. Air conditioners often dehumidify spaces, so check whether a dirty evaporator coil is causing moisture to accumulate inside. Let the frozen AC lines thaw out, and clean the filters and dirty evaporator coil as needed. Avoid using your unit in cold weather.
#5 Blower Fan Failure
You may notice the airflow around your unit getting weaker despite using the highest fan mode setting. This may be due to a problem with your blower fan. A malfunctioning blower fan cannot direct the cooled air out of the unit, while the exhaust unit continues to remove warm air from inside the air conditioner. As a result, the unit’s evaporator coil freezes.
For blower motor and fan blade problems, it is best to leave the issue to the professionals as they will be able to assess and determine the root cause of the problem. Have your faulty fan motor replaced, and have a professional check your air conditioner from the compressor to the evaporator coil for a thorough checkup.
How to Spot a Frozen AC Line?
If your air conditioner is not cooling properly, blowing warm air, or showing visible frost on the refrigerant lines, it may be frozen. Another telltale sign is reduced airflow, where the AC struggles to push out cool air despite running. In some cases, you might also hear unusual hissing sounds due to pressure buildup. Several of our clients in Singapore, particularly in offices and retail spaces, have encountered this issue, often due to neglected maintenance or clogged filters.
How to Fix Frozen AC?
If you suspect your AC line is frozen, the first step is to turn off the unit immediately. Continuing to run it can damage the compressor, leading to costly repairs. Allow the ice to thaw naturally by switching the system to "fan mode" for a few hours. Meanwhile, check and clean the air filters, as dirty filters are a common cause of restricted airflow leading to freezing.
As we mentioned, another possible culprit of frozen AC is low refrigerant levels, which require professional servicing. Many AC servicing companies in Singapore such as Luce offer regular maintenance plans to prevent such issues, ensuring optimal performance in Singapore's tropical climate!
5 Tips to Prevent Your AC Lines from Freezing
Air conditioning systems can be low-maintenance units with proper care, as the majority of AC problems are caused by dust and dirt accumulation in the unit. Here are 5 tips you can do to prevent your AC lines from freezing up in the future:
- Clean your air conditioner thoroughly. Wash the air filter at least once every two weeks to remove dust accumulation, and vacuum up the evaporator coils as well. Give your outdoor unit a good rinse with the garden hose on a hot day to dislodge any debris inside.
- Avoid using your AC unit in cold weather. Cool temperatures can cause moisture inside your AC unit to freeze, so it is best to use the heater setting of your unit or keep the temperature on a moderately high level to prevent a frozen AC line.
- Have your unit professionally checked. Your HVAC system will benefit from a professional checkup by one of our Luce Aircon technicians. Have our technicians check your unit every 4-6 months for the best care.
- Avoid overworking your AC unit. An overworked air conditioning system is more likely to break down faster. Use your HVAC systems only as needed, and let the air conditioning unit cool down after a long period of use.
- Keep the vents clear. This will keep the airflow circulating in the room and prevent the cooled air from freezing up your AC line.
When to Call the Professionals
When it's time to call the professionals, contact us at Luce. Our technicians will be able to clean, assess, and repair any air conditioner problems across most brands and models in Singapore! You can be assured we'll find the cause of the problem and fix it for good.
Give us a call today to schedule your next cleaning or maintenance session!
Check out our article on aircon ice build up!
