Identifying why compressor failure is subject to many variables and is important to understanding warranty implications. Although compressors fail for a multitude of reasons, poor installation and maintenance are the most common causes. However, for the vast majority of compressors returned for claims, rarely is it due to a defect in the manufacturer supplied part.
Determining why a compressor has failed is a challenge for contractors of light commercial cooling systems. The mere fact that installation and maintenance procedures are key factors means that most compressor failures are preventable. Therefore, it is of the utmost importance to understand the various ways in which these failures occur.
Following OEM guidelines for installation, startup and service are critical for installers of both ducted and ductless systems. For instance, the act of completing a compressor changeout can introduce contaminants to an HVAC system. Conversely, there is the rare occurrence of natural causes such as lightning or line voltage fluctuations that happen. On the other hand, proper routine maintenance improves the long-term reliability of the system.
This allows technicians to identify issues before they can cause a catastrophic failure. For instance, a dirty outdoor unit coil will result in the inability to reject heat, thus increasing compressor operating temperatures. When this happens, the compressor forces more expended energy while providing less capacity. Therefore, regular routine maintenance is key to keeping a system running well and avoiding compressor breakdown.
Other factors that affect compressor life
When it comes to compressor endurance, keeping refrigerant lines free of moisture or oxidization is very important. When refrigerant lines become contaminated it causes the internal lubricant to become acidic, which can eat away at internal windings.
Another factor contributing to compressor failure is incorrect refrigerant line sizing. When this occurs, it affects pressurization and evacuation to ensure the absence of leaks. It is also important to have correct minimum unit clearance and refrigerant charging procedures. These factors are critical to longevity and the life expectancy of the compressor.
Overheating is yet another variable that causes compressors to lose their operating capabilities. This usually happens when there is not enough refrigerant in the system. When overheating happens over an extended period it will cause the breakdown of winding insulation. Symptoms of overheating may include compressor short cycling due to increased trips on protection devices. This reduces heating and/or cooling performance, and an increases current draw.
Training and Startup Procedures
Contractors can help mitigate the chances of compressor failure by adhering to each manufacture’s startup procedure. This is because each manufacture has unique steps that must transpire in order to keep equipment running smoothly. Finally, attending a manufacturer training session is a good step in achieving longevity in HVAC systems.