The compressor is the part of your HVAC unit that compresses the refrigerant so that it can attain the right temperature and pressure. This means your house won't be comfortable if the compressor isn't operating optimally. As such, the compressor is one of the most vital parts of the HVAC system, and you don't want it to ever fail. Here are some of the common things that lead to compressor failure:
Blocked Coils or Suction Lines
Anything that interferes with the free flow of air or refrigerant in the HVAC system can damage the compressor. For example, if the condenser coils are covered in dirt and grime, the heat generated by the unit won't be expelled, and it will be forced to run continually. In such a case, the compressor will face higher temperatures and pressures than it was designed to handle. The same thing can happen if the refrigerant lines are blocked. This is why cleaning the HVAC and ensuring the free flow of suction lines should always be a major component of all its maintenance schedules.
Every electromechanical system needs its moving parts well lubricated to reduce friction and the associated overheating. Therefore, if your unit isn't properly lubricated, all its parts that need lubrication to operate properly (and the compressor is one of them) may fail. Luckily, you can always top off the lubricant and prevent serious damage if the levels fall below the specified limits.
Wrong Refrigerant Levels
Every compressor is designed to handle a specific volume of refrigerant; give or take a little. Since the compressor's main job is to compress the refrigerant, too much or little refrigerant can interfere with its operations. For example, if the refrigerant lines are leaking and the volume of the refrigerant falls, the compressor will try to overwork to maintain the volume flowing through the system, and this may cause its failure.
As previously mentioned, the compressor is an electromechanical system, which means it has both electrical and mechanical parts; failure in any of these parts can lead to the compressor's failure. Since it's the electronics that control the whole system, electrical failure (such as burnout) can lead to its malfunction and eventual failure.
Considering all the above, it's clear that you should never assume that your system's compressor is safe; you need preventive maintenance to ensure it's actually safe. The best person to ensure this is the case is a professional HVAC technician, such as Airwaves Heating & Air Inc, via regular servicing of the system.