What to Do When Your AC Condenser Is Defrosted

Common Causes

• A frozen condenser can cause your air conditioner to overheat or prevent cold air from entering the home from the evaporator and vents. Causes of a frozen condenser can be an unclean air filter, blocked evaporator coil, blocked supply register or grille, a non-working blower motor or low refrigerant. You can rectify many of these problems without calling a professional. However, more serious problems, such as a frozen condenser with a burning smell or loud sounds coming from the outdoor unit, should be investigated and repaired by a professional.

Solutions

• If your condenser is frozen due to a dirty filter, turn off the air conditioner, remove the filter and clean or replace it. While doing this, switch on the fan function on your air conditioner to assist in thawing the condenser. If the evaporator coil is dirty or clogged, switch off the air conditioner and clean it with a cleaner and brush designed for use on the coil. If you have a grille placed low on the wall and a piece of furniture is significantly blocking it, move the piece of furniture, turn on the fan and allow the condenser to defrost before running it in the cool mode.

Non-Functional Motor

• One of the main causes of a frozen condenser is a non-functional blower motor. If you turn on your air conditioner and no air comes through the vents or you don’t hear the motor running, you may have a bad blower motor. This is caused by a lack of liquid leaving the compressor for cooling or a lack of liquid flowing from the condenser into the evaporator. Switch off your air conditioner to prevent overheating. Check for a burning smell and if the outdoor unit is hot to the touch or if ice or frost is present on the coil. Manually restart the motor by using a hard thin object to spin the fan while the unit is on; exercise caution when doing this as you can be seriously injured. If you cannot move the fan, the motor is no good and will have to be replaced.

Prevention

• After fixing the unit you can run it as usual. To prevent problems from reoccurring check your unit monthly, replace the filter according to the manufacturer’s instructions and keep all wall grilles unblocked and free from debris or dust. If you do not feel confident checking your system, have an air conditioner company service your unit every few months to prevent pricey repairs.