How To Make Window Air Conditoner Fit Large Window

Window air conditioner units provide cool relief on hot days, but selecting the right unit requires some preparation.

In addition to room size and power-source availability, you should always consider the size of the window when purchasing a window air conditioner.

A small window can support only a small unit.

Larger windows can support a variety of sizes, but sealing the extra space is crucial.

Close off the space remaining in large windows using premade or customized extension panels.

How to Make Window Air Conditoner Fit Large Window

Install mounting hardware per manufacturer's instructions

Install the mounting hardware per the manufacturer's instructions, then slide the air conditioner unit into place. Close the window.

Assemble and install extension panels to completely seal off window opening

Assemble and install extension panels to completely seal off the window opening. Some window air conditioner models come with preinstalled extensions that simply need to be pulled out from the sides of the unit until they close the gap in the window. Some manufacturers sell expansion panels that attach to and extend the existing extension panels. For air conditioners without extension panels, an acrylic sheet cut to size provides the necessary protection. Ensure that your measurements are accurate before you cut the acrylic sheet. You can also use plywood to seal off the opening.

Seal around extension panels or acrylic sheet using wea r stripping or tape

Seal around the extension panels or acrylic sheet using weather stripping or tape.

Install weather stripping to insulate any gaps in the window sashes.

The manufacturer often includes foam weather stripping.

If not, purchase the stripping from the hardware section of many stores.

Prevent drafts by caulking around the outside of the air conditioner unit.

Prevent drafts by caulking around the outside of the air conditioner unit.