2 Common Causes of Air Conditioner Compressor Burnout

07/07/18

All air conditioners rely on the component known as the compressor to circulate refrigerant throughout the system. The compressor achieves this task by increasing the pressure and velocity of the gaseous refrigerant returning from the evaporator coil. Without a working compressor, your air conditioning system simply wouldn’t be able to cool your home.

Unfortunately, the heavy workload faced by a compressor makes it susceptible to developing problems as time goes on. The likelihood of such problems grows when other factors happen to be at play. This article will provide you with vital information about how to keep your AC running strong by discussing two common causes of premature compressor burnout.

1. Restricted Expansion Valve

All air conditioning systems contain a category of components known as meter devices. The most common type of metering device found in residential systems goes by the name of a thermostatic expansion valve. This valve can be found on the liquid line leading from your condenser to your indoor evaporator coil.

The expansion valve limits the flow of refrigerant into the evaporator coil. This creates a low-pressure environment inside of the coil, which in turn causes the refrigerant that enters to drop even further in temperature. As a result, the refrigerant can absorb more heat from your home’s air.

An expansion valve’s orifice tends to be tiny. After all, that’s how it manages to limit the refrigerant flow. Unfortunately, however, this structural feature also puts the expansion valve at risk of becoming clogged or overly restricted by debris in the system. If too much sludge builds up inside the expansion valve, refrigerant may not be able to enter the evaporator coil at all.

This kind of restriction leads to system-wide problems. Refrigerant will back up inside of the liquid line and condenser. The evaporator coil and compressor, on the other hand, will become starved of refrigerant. As the compressor attempts to restore flow by working harder, it often overheats and burns out entirely.

If you’ve noticed that your system has suddenly ceased to provide normal cooling levels, a restricted expansion valve may be at the root of the problem. To restore proper cooling, and to prevent other parts of your system from becoming damaged, you must hire a professional to attend to the problem as quickly as possible.

2. Lack of Lubrication

Compressors rely on oil in order to provide consistent results. This oil provides three key benefits. First, it lubricates the moving parts of the compressor, preventing damage caused by friction. Second, the oil helps to remove any heat generated by the compressor’s operation. Third, the oil promotes a leak-proof seal, ensuring that refrigerant stays where it should.

Over time, a compressor will gradually lose its lubricating oil. Some of this oil may work its way into the refrigerant. Some of the oil may leak or drip away from the places where it is most needed. Finally, some of it may degrade to the point that it can no longer provide effective lubrication. In all three cases, your compressor may end up without the oil it needs.

Just as with an automotive engine, a lack of oil can devastate an air conditioning compressor. Internal friction levels will rise, as will the average operating temperature. Both of these factors greatly increase the chances that the compressor will break down, overheat, or suffer other catastrophic issues.

Fortunately, regular servicing is all it takes to ensure that your compressor stays properly lubricated. For more information about keeping your AC in peak operating condition, please don’t hesitate to contact the HVAC industry experts at HELP Plumbing, Heating, Cooling and Drains.

Posted in: Air Conditioning, Cooling, Knowledgebase