Air conditioner has become a staple of the modern home during the summer months, when high temperatures begin to make things a bit uncomfortable indoors. But for all of our use of cooling systems, most homeowners would be hard-pressed to describe what actually goes on during the so-called refrigerant cycle. It’s the same process that refrigeration equipment uses to keep your perishable goods fresh. With the exception of swamp coolers, all air conditioning systems use a very similar process, which we outline below. Knowing more about how your air conditioner works can be useful when recognizing the signs that something is wrong.

The basic split setup for air conditioning comprises an indoor unit, which houses the evaporator coil and air handler, and the outdoor unit, which houses the compressor and the condenser coil. They are connected by piping that transfers refrigerant throughout the various components. Since we have to begin somewhere within the refrigerant cycle, we’ll start at the compressor. When you call for cooling, your compressor pressurizes a low-temperature, low-pressure gas refrigerant into a high-temperature, high-pressure gas. It is now ready to phase-change into a liquid by means of the condenser coil and the outdoor exhaust fan.

But it is still not quite cold enough to be useful as a cooling medium. After the condenser, it travels through an expansion valve that meters the flow of the liquid refrigerant, thus dropping its pressure and cooling it substantially. By the time the refrigerant has reached your indoor evaporator coil, it is ready to interact with your warm indoor air, which causes the refrigerant to evaporate as it passes through. Then the cycle repeats itself. That is the basic process by which air conditioners cool your indoor air, though there are significant variations thereof, and swamp cooling is a whole other beast entirely.

Know that you know a little about how air conditioning works, make sure to keep an eye out for any signs that you might need AC service. If you notice any frost build-up on the coils or any strange noises coming from your cooling system, give us a call.

APC Plumbing & Heating offers professional air conditioning services throughout the Denver, CO area.