Tips for Buying a New Room Air Conditioner

• When shopping for an air conditioner, first determine which type of system best suits your needs- central air conditioning or room air conditioning. Central air conditioners are designed to cool an entire house, while room air conditioners are usually window-or wall-mounted units that only cool the immediate area.
• Three types of room air conditioners are available: (1) window models that can be installed in most double-hung windows; (2) casement window models that are used in narrow, vertical windows, usually requiring the removal of a window panel for installation; and (3) built-in models that are encased in a sleeve installed in the wall.
• Proper sizing is very important for efficient air conditioning. A bigger unit is not necessarily better because a unit that is too large will not cool an area uniformly. A small unit running for an extended period operates more efficiently and is more effective at dehumidifying than a large unit that cycles on and off too frequently.
• When determining the appropriate size air conditioner for your home, consider the dimensions of the area to be cooled. Based on size alone, an air conditioner generally needs 20 Btu for each square foot of living space. Other important factors to consider when selecting an air conditioner are room height, local climate, shading, window size, etc.
• Verify that your home's electrical system can meet the unit's power requirements. Room units operate on 115-volt or 230-volt circuits. The standard household receptacle is a connection for a 115-volt branch circuit. Large room units rated at 115 volts may require a dedicated circuit and room units rated at 230 volts may require a special circuit.
• If you are mounting your air conditioner near the corner of a room, look for a unit with an airflow in the desired direction for your room layout.
• Look for a unit whose filter slides out easily for regular cleaning.
• Select a unit with logically arranged controls, a digital readout for the thermostat setting, and a built-in timer.
• When considering several comparable units, select the unit with the higher EER.
• If you need to mount the air conditioner at the narrow end of a long room, then look for a fan control known as "Power Thrust" or "Super Thrust" that sends the cooled air farther into the room.

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