It’s normal for your air conditioner to be cold when it’s in use, but if it is covered in ice, that’s a bad sign. This means your unit is freezing up, which will prevent it from cooling your home down to a comfortable temperature. Additionally, if the problem isn’t addressed right away, you could end up with water damage in the walls and ceiling, as well as compressor failure. Therefore, it’s essential to be aware of the common reasons air conditioners freeze and what you can do about it.

3 Explanations Why Air Conditioner Units Freeze 

1. Insufficient Airflow

An air conditioner will often freeze up if there isn’t enough air flowing over the evaporator coils. This can happen when something is blocking airflow, such as clogged air filters, closed dampers, or obstructions in the ductwork. The system won’t be able to pull enough heat in to keep the condensation on the coils from forming into ice. Replacing air filters may take care of the problem, but if it continues, a technician should be called in to inspect the ducts and HVAC system.

2. Refrigerant Leaks 

The refrigerant inside an air conditioner’s evaporator coils is designed to absorb heat from the air inside a home and transfer it outside. However, to do this correctly, the unit must have the right amount of refrigerant. If your air conditioner has a refrigerant leak, there won’t be enough to adequately remove heat from the air. As a result, the evaporator coils will remain cold and eventually freeze over. It’s likely you will need an HVAC contractor to find the source of the leak and replace the missing refrigerant.  

3. Dirty Coils 

If dirt and dust particles are allowed to accumulate on the evaporator coils, an extra layer will lie between the refrigerant inside the coils and the warm air that blows over them. This makes it difficult for the coils to absorb the heat necessary to stop condensation from getting too cold and turning to ice. Having the evaporator coils professionally cleaned bi-annually can help avoid this issue. 

Should you start to notice your air conditioner freezing, have an HVAC contractor diagnose the cause. The technicians at Overcashier & Horst Heating and Air Conditioning offer more than six decades of industry experience and have helped numerous Sylvania, OH, residents avoid freeze problems. They provide thorough preventative maintenance services to keep minor issues from becoming costly repairs. Call (419) 841-3333 to schedule a tuneup, or visit them online to learn more.