You've probably read that air conditioning systems can last around 10-15 years, but why do they eventually require replacement? As with most significant appliances, homeowners typically replace their air conditioners when repair costs begin to exceed replacement costs. For central air conditioning systems, a compressor failure is usually the last straw.
The compressor is one of the most expensive items in your air conditioner, and a faulty one can often put the last nail in the coffin of a dying system. As a result, the best way to keep your system going for as long as possible is to treat your compressor well. If you want your air conditioner to last to a ripe old age, avoid these three situations that can cause significant damage.
1. Short Cycling
While you might usually measure the life of an air conditioning system in years, it's arguably better to consider its hours of runtime and start-stop cycles. Each time your compressor turns on, its internal parts wear down a bit more. The compressor may turn on many times during hot days, but a system performing well should remain idle for a significant portion of each hour.
If your compressor turns on and off rapidly, you may be suffering from a short cycling condition. Short cycling can rapidly wear out your compressor and blower motor, and it's an excellent way to cut an air conditioner's life short. Be sure to pay attention to your AC's normal cycling behavior, and contact a professional if you notice it cycling more often than it should.
2. Refrigerant Leaks
Your compressor acts as a pump, and refrigerant can't cycle between the system's evaporator and condenser without it. However, unlike a traditional pump, your compressor takes the relatively low-pressure return vapor and compresses it into a high-pressure, high-temperature gas. To accomplish this efficiently, it relies on a specific total pressure within the refrigerant lines.
Any change in your refrigerant level (too low or too high) can force the compressor to overwork itself. Just like the engine in your car, pushing your compressor motor too hard can cause it to overheat, resulting in internal heat and friction damage. Although compressors contain safety measures to shut down in these situations, you should still never attempt to run a system with leaking refrigerant.
3. Frozen Evaporators
A frozen evaporator can also strain your compressor. Evaporators can freeze due to low refrigerant pressure, but poor airflow can also sometimes cause ice to form. Ice acts as an insulator, preventing the refrigerant from taking up the heat in your home. The compressor will struggle with the cooler return refrigerant, potentially wearing out its internal parts more rapidly.
Frozen evaporators may cause short cycling or humid air since your blower will push moisture from the ice into your vents. If you notice these symptoms, stop using your air conditioner as soon as possible and call in a technician to diagnose and repair the problem. For more information, contact an AC technician near you.