An Introduction to Air Conditioning Systems
Author: John Published Under: Home
Heating and Air is an essential part of any home, which helps keep the home cool in the summer and warm in the winter. In older times, most people relied upon wood burning stoves to provide heat and windows to provide air, but today, most people have some sort of Heating and Air Conditioning Ventilation System(HVAC.) One of the key components of these systems is the compressor.
There are actually several different types of compressors, but before these are discussed, it is important to know the difference between a Closed System and an Open System.
Open Systems
Open Systems, which are often called Open Drive Systems, feature a compressor that is driven by an external motor. This makes it easier to service, but requires that the system have very tight seals around the motors crankshaft. Usually the compressor is belt driven.
Closed Systems
Closed Systems, or Closed Drive Systems, enclose the compressor and inside of a housing. This means that having tight seals around the crankshaft is not required, as would be in a open system, and the electric motor is also cooled by the air conditioning vapors, but they are not always as easy to service. Also, the electric motor can not use brushes, as this would cause sparks, which could contaminate the air conditioning vapors.
There are several types of closed systems, with a Full Hermetic System, using a welded housing, so that if the motor or compressor breaks, the entire housing must be replaced. Serviceable hermetic systems, which are sometimes called semi-hermetic systems, use a gasket seal on the housing, so that the individual components can be serviced.
How a Compressor Keeps Cool
It might seem odd, but generating cool air actually creates a lot of heat as a byproduct. Without some way to deal with this heat, the compressor would overheat very quickly, so cooling the compressor is very important.
The way that the heat generated by a compressor is dealt with varies, depending on the type of compressor used, but most rely on some sort of water passage or by using fins.
In Closed Systems, a suction line feeds cool refrigerant directly to the cylinder heads. As a result, having proper pressure and suction-gas temperature are critical to this type of system. If the pressure is too low, most systems have a low-pressure cut off switch, which protects the air conditioning.
There are also some systems that are air cooled, using the condenser fan or a fan specifically for cooling.
Water cooled compressors allow water to circulate through the head. The heat trapped from this water is sent to the condenser or simply dumped from the hvac system.
Types of Air Conditioning Compressors
There are many different air conditioning manufacturers and countless models, but they all rely on some sort of compressor to cool the air. There are five basic types of compressors, specifically Centrifugal Compressors, screw driven Helical Compressors, Rotary Compressors, Scroll Compressors, and Reciprocating Compressors.
Learn More About the different types of air conditioning compressors.