The cause is a failure in the edge seal that secures the individual panes of glass.
How to seal off a window unit.
Gaps around an unsealed air conditioning unit will allow.
Stick the plastic to the tape taking care to seal off the window at every corner and side.
This means both covering the outside body of the ac unit with a plastic bag to weatherize it and then covering it with a heavy fabric cover to protect it from the elements.
Window air conditioners sit on the windowsill and typically have accordion style fins on either side of the unit that act to seal off the window.
Re close the window tightly.
Then lift the window and place the seal under the lip of the window.
Press the plastic over the tape to ensure a good seal and effectively seal any remaining cold air that could enter your home through the window air conditioner.
The symptoms of failed window seals are easy to spot.
However it is important to properly seal them to avoid energy loss.
Most window air conditioners come with an accordion style flap attached to the sides to fill the open.
The multi pane glass develops condensation or fogginess that can t be wiped off from either side of the window.
Window air conditioners are an affordable option for home cooling.
Most window air conditioners have an expanding curtain on either side to help seal any gaps between the window frame and the air conditioner but sometimes this seal isn t perfect.
Step 3 examine the sash.