A frozen AC unit can be frustrating. Not only will it not run, but it can take hours to defrost only to become frozen again after a short period of use. If you’re struggling with a frozen AC, the cause may be one of these four common reasons. To help get your AC back up and running, Spoor’s Heating & Air Conditioning is reviewing what causes an AC to freeze and what you can do to solve this issue. Need fast and reliable HVAC services? Call us today to schedule an appointment!


Low Refrigerant

Refrigerant is responsible for cooling the air in your HVAC system, but your system won’t be able to provide proper cooling if there is low refrigerant. While it seems contrary to logic, low refrigerant levels can cause the temperatures on the evaporator coils to drop below freezing, causing the HVAC unit to freeze up. Low refrigerant levels typically mean there is a leak, which should be addressed ASAP by a professionalHVAC technicianbecause refrigerant can be dangerous if exposed to people or pets.   

Clogged Drain Line

The drain line is responsible for removing collected water from humidity out of the system. If the line is clogged, the water can’t be removed, which may cause the evaporator coils to freeze up. If the drain line is clogged, you may notice water leaking from the HVAC unit. If you have access to a wet/dry vac, you may be able to clear the line yourself, though we suggest contacting an HVAC company for safe and effective drain line cleaning. 

Poor Airflow

Adequate airflow is paramount for your HVAC unit to function properly. Without it, not only will the AC have trouble working, but the unit may also become frozen. There can be several reasons for poor airflow, including blocked vents, a dirty air filter, or an issue with the blower motor or fan. Air filters should be changed approximately every two to three months, depending on where you live and how many people and pets live in your home. Not only is this important for goodindoor air quality, but routinely placing your air filter can prevent damage from occurring in the HVAC system. For air vents and registers, it’s important to maintain a clear space of at least six inches. This way, air can flow freely without creating issues with the system or in the air ducts. For the blower motor and fan, the issue may be an old or damaged part, loose connection, or low power draw. Because of the technical and electrical nature of these components, it’s best to have them inspected by a professional who can provide expertAC repairs.

Dirty Coils

The coils on the outside portion of the HVAC unit can become dirty over time from natural exposure to the elements, dirt, grime, leaves, and debris. Similar to the air filter, the coils need to be clean for the unit to properly function. To prevent the coils from becoming clogged, clean them off once every few months or after a heavy storm or lawn care. To clean the unit, make sure it’s off and use a broom to sweep away larger debris, then wash the unit off with a garden hose. We can also take care of cleaning the unit for you during regularHVAC maintenance.