Learning About Commercial HVAC Systems
About Me
Learning About Commercial HVAC Systems

Hello, my name is Jacob. I would like to talk about proper installation and repair of the HVAC system in your commercial building. Full scale HVAC systems for commercial buildings require ongoing maintenance and repairs to keep every floor and room at a comfortable temperature. These temperature control systems also control the air quality in the building by sending the airflow through filter elements. My site will cover all aspects of the upkeep needed for these systems. I will also talk about the benefits of keeping your air quality and temperatures at desirable levels. Thanks for coming to visit my website.

Learning About Commercial HVAC Systems

Are Frozen Evaporator Coils Causing Problems With Your Mini-Split System?

Isaiah Chapman

Mini-split air conditioning systems may be smaller than other air conditioners, but these energy efficient systems are surprisingly powerful, and are widely used in both homes and commercial buildings across the country. Most mini-split systems are also very reliable, and do not require much maintenance to stay functional.

Unfortunately, mini-split systems can still suffer problems caused by poor maintenance or accidental damage, and frozen evaporator coils can be a particularly troublesome problem. Here is everything you need to know about how frozen evaporator coils can affect mini-split air conditioning systems.

How Do Frozen Evaporator Coils Affect Mini-Split Systems?

The evaporator coils in a mini-split air conditioning system are located inside the system's indoor blower unit. When the system is functioning, a constant supply of refrigerant flows through these coils, absorbing heat energy from the air around the coil. The chilled air is then vented back into the room using the unit's blower fan.

You might assume that, because evaporator coils are supposed to cool air, a frozen evaporator coil will cool it even more. However, ice is actually a remarkably effective heat insulator. If an evaporator coil becomes coated in a layer of ice crystals, it loses its ability to absorb heat energy, seriously undermining the cooling power of the affected unit.

Why Do Evaporator Coils Freeze?

Two major underlying problems can cause your mini-split system's evaporator coils to become frozen:

Insufficient Refrigerant

As refrigerant liquid flows through an evaporator coil, the refrigerant evaporates into a gas, absorbing heat energy as it evaporates and its molecules expand. If the coil is not receiving enough refrigerant, the refrigerant molecules will expand too much, causing the coil to become too cold and freeze.

A blockage in the system's refrigerant line is a common cause of frozen evaporator coils. Your coils may also have low refrigerant levels if there is a leak in the refrigerant line; this is a potentially dangerous problem, as refrigerant gases are toxic if inhaled.

Dirty Evaporator Coils

Over time, dust particles and other solid debris will accumulate on the outer surfaces of a refrigerant coil. This will happen more quickly if the mini-split system is used frequently, or if you live in an urban area where the air contains high quantities of particulate matter. A thick layer of dust on the outside of a refrigerant coil will prevent it from absorbing heat energy, causing the coil to become too cold.

What Should You Do If Your Mini-Split System's Evaporator Coils Freeze?

If your mini-split system's evaporator coils have frozen, you should deactivate the system as soon as possible and allow the ice to melt. Running a system with frozen evaporator coils for long periods can cause serious damage to your system. Running a frozen mini-split system is useless anyway, since a frozen system cannot create significant amounts of cold air.

Once the coil has defrosted (use a bucket or tray to catch liquid water dripping from the unit), visually inspect the coil for signs of dust accumulation. If the coil is dirty, it can be cleaned using a mixture of water and ordinary household detergent.

If the coil is not visibly dirty, or you are not comfortable cleaning a dirty coil yourself, call in a professional air conditioning system repair service. These services can use proprietary cleaning chemicals and equipment to thoroughly clean evaporator coils, and will also be able to diagnose and fix any problems with your mini-split system's refrigerant supply.