How To Keep Your AC Compressor From Overheating

21 June 2016
 Categories: , Articles


If you have a central air conditioning unit, then you likely know that the large box-shaped portion of the device that sits outside your home is called the condenser. This part of the system will contain a compressor pump, a series of refrigerant lines, a fan, a fan motor, and metal grates. One of the most important components of the condenser is called the compressor. The compressor is a pump that places the refrigerant under pressure and moves it through the cooling system. Without the AC compressor, the HVAC system would no longer cool your home, and hot air would likely blow through your vents. Unfortunately, the compressor can overheat and then fail completely. Keep reading to understand how to prevent this from happening.

Make Sure The Unit Has Some Clearance

Many HVAC professionals will inform you that you should not place plants, shrubs, or trees close the condenser unit. This is necessary for several different reasons. Keeping greenery away helps to keep leaves and other debris from blocking the fan or the metal cooling grates on the side of the AC unit. It also allows air flow to move quickly and evenly through the grates. Air flow is extremely important in keeping the compressor cool. The refrigerant that passes through the condenser unit will come from inside your house. This is where the refrigerant absorbs heat from the inside air so cooler air can move through the vents. As the hot refrigerant moves through the condenser unit, it releases the heat. The fan on the top of the unit pulls air through the grates on the side of the condenser. The air moves past the refrigerant lines and up through the fan.

Once the refrigerant has been cooled, it moves into the compressor. The pump then compresses the coolant and places it under pressure. If the coolant is warm when this happens, then the pump will absorb the heat. The pump itself also creates some heat. Since there is not good air flow around the compressor, the heat cannot be dispelled easily and the pump can overheat. Typically, seals within the compressor will break down and the motor will burn out as well. 

To reduce air flow issues, make sure that the condenser has at least one to three feet of open space along the sides and four to six feet above the unit. More space around the unit is better for air flow. However, the condenser itself can absorb heat from the sun if it is left in an open area. This means that a well-placed tree that sits at least several feet away from the unit may be a good idea to reduce thermal heat gain. 

Have The Compressor Oil Changed

The compressor motor is like any other motor; it needs lubrication to reduce heat and friction from wearing down the moving parts. In the case of the compressor, the oil keeps the piston rings and cylinder in good shape. The oil used to lubricate the moving parts of the compressor will break down over time. This means you may need to add some oil to the system.

The compressor oil will move through the cooling system with the refrigerant, and your AC system will not cool as well as it should if too much oil is added. This means that the oil may need to be drained out of the compressor and replaced completely to ensure that the right amount is held in the system. Oil amounts and types will vary depending on the type of HVAC system that you own. You can look in the manual for your HVAC system for this information. However, since oil does not need to be added very often, consider asking your HVAC technician to change the compressor oil during your annual inspection. This should be enough to make sure that enough viscous oil is running through the system. 

For more information, contact a company like United Heating Cooling and Plumbing Inc.