If you have a window air conditioning unit that you cannot remove when not in use during the colder months, consider investing in an insulated cover for it. Home improvement stores have specially made covers that fit snug on the inside and exterior part of the air conditioner. They are waterproof and tough (so they can withstand the elements), but they also block cold drafts from blowing into your house. These covers pay for themselves over time in energy savings.
ANDREWS MCMEEL SYNDICATION