Installing a Window Air Conditioner

Frigidaire Window Air Conditioner

Window air conditioning units may not be as efficient as a central air conditioner, but if you only need to cool a single room rather than the whole house, they may be more cost effective. Standard window units drawing less than 7.5 amps can be plugged into any household electrical outlet as long as it is not sharing the circuit with another major appliance. While installing a window air conditioning unit is not complicated, doing a little prior planning can save time, money and energy.

Things You'll Need

• Window air conditioner with hardware
• Measuring tape
• Screwdriver
• Screws
• Foam weather stripping
• Exterior caulk
• Caulk gun
• Level

Instructions

1. Open the window to its widest point. Ensure the wood on the window sill is solid. Wood sills that appear blistered or have pin holes with grainy, sand-sized pellets may indicate the presence of termites. Use an ice pick or thin screwdriver to probe the wood. If the pick penetrates the wood with only moderate pressure, the wood is too soft or too damaged to support a window air conditioner. Do not install the mounting brackets on wood that is partially rotten or damaged by termites.

2. Most modern window units are supported by sill-mounted brackets only. However, many older models and some of the larger modern units will require external brackets. For these units, center the bracket on the window sill. Secure the bracket with sheet-metal screws on a metal frame or wood screws on a wood or vinyl frame. Place the level across the bracket and sill. Adjust the bracket with the exterior support leg. Secure the support leg to the exterior wall with wood screws, sheet metal screws or masonry screws as required.

3. For units without an external bracket, install the sill-mounted bracket by screwing one side of the bracket to the window sill. Place the level on across the window sill and bracket from from to back. Adjust the level by turning the center screw.

4. Set the air conditioning unit into place and slide it backwards on the mounting bracket until the lower pocket locks into place. Lower the window onto the top of the unit. Pull the extensions on either side of the air conditioner until they are flush against the window frame. Secure the extensions to the sash with the fasteners that came with the unit.

5. Most window air conditioning units come with an "L" bracket to secure the window sashes to prevent accidental opening of the window. Ensure this bracket is properly attached. If these are not included with your unit, it is a good idea to purchase them yourself as a precaution. Seal any gaps around the perimeter of the window unit with foam weather stripping. Finish the installation by caulking around the exterior of the unit.

Tips & Warnings

• When you buy your unit, determine the number of BTU you need by multiplying the total square footage of the room by 20. A 200-square foot room would need at least 4,000 BTU. Although the installation process for most window air conditioners is quite similar, there are peculiarities specific to each manufacturer. Be sure to install the mounting hardware according to the manufacturer's instructions. Window units that are not in direct sunlight will operate more efficiently that those that are. Don't allow trees or shrubs to grow too close to the window unit. These units need room for air flow in order to operate efficiently. Using an oscillating fan in addition to a window unit will help to distribute the cool air throughout the room and save energy.

• Failing to follow the manufacturer's instructions may result in the unit falling from the window, resulting in damage to the unit and possible injury to anyone underneath it. Do not install the mounting brackets on wood that is partially rotten or damaged by termites. The wood may not support the weight of the air condition. Remember to lift with your legs, not your back, and if the window unit is heavy you may require assistance with this procedure.

Resources

• Lowe's Window Air Conditioner Buying Guide