For small spaces, a room air conditioner can be just the right type of cooling system to bring relief from the summer heat. The most common type of room air conditioners are rather small and are designed to be installed either into an external wall or into a window so that the unit has good ventilation and airflow. In recent years, portable air conditioning units have also been introduced, which feature a flexible hose for venting and casters for ease of movement to different rooms.
The function of air conditioning equipment for a room is to cool the air inside a small, confined area. They are not designed for, or intended to be used, as a whole house air conditioning system. They are predominantly used in houses or apartments where folks are renters. Consequently, they are not permanent fixtures and can be removed and taken to a new location if the tenant moves home.
Most folks are unaware that room air conditioning units in reality, do not cool a room at all. The correct terminology is to say that a room air conditioner takes away the heat from the air and then moves it to another place where the unit has been vented.
How Does a Room Air Conditioner Work
When turned on, pressurized refrigerant, termed R-22, flows through the air conditioner unit. At the same time, the condenser will pull the refrigerant gas into the air conditioning system and then pressurize it, which in turn raises the temperature of the gas. This heated, high-pressure gas travels next to the condenser coils, which are located on the outdoor section of the unit where the fans distribute the heat that has collected.
The cooled gas then becomes condensed into a liquid, which moves to the interior part of the room air conditioner to the evaporator coils. At this point, these coils can absorb the heat that is in the room. The fan then moves the air throughout the unit. The thermostat controls the cycling of this process to maintain the desired temperature in the room.
Several room air conditioners have mechanical controls, such as knobs and push buttons. More recent air conditioning units are controlled with electronic touch-pads that tend to offer more functionality and can regulate the mode the units operate in, the temperature set point, a timer for automatic shut off and powering on, and an assortment of other conveniences, the majority of which are intended to make the unit as energy efficient as possible.
The majority of room air conditioner units include a built-in control panel, which is either on the front of the unit or on the top near the front. Positioning is such that the user is able to easily see and adjust the controls. Normally, there are two sets of controls, which are for the temperature setting adjustment and the other to control the fan speed.
Room Air Conditioner Efficiency Ratings
To make it easier and clearer for folks to choose the best room air conditioner, all types of air conditioners carry a label with a rating of their energy efficiency. This is a service of the US Department of Energy termed the Energy Star rating. Taking the cooling capacity of BTUs and dividing that by the watts of energy used derives the EER, or Energy Efficiency Rating. In order to carry an Energy Star rating, the model must have an EER of at least 10 percent higher than competing models.