Locate the pipes leading from the air conditioner to the evaporator. This pipe can typically be found coming out of the outdoor air conditioning unit into your home and down near the furnace. However, the exact location of the pipe can vary according to the unit's design. Check your owner’s manual to determine where this pipe is located.
Remove any dirt and debris on the pipes with a soft rag and a mild cleanser.
Gather your insulation materials. While fiberglass and foil insulation may be used, over time these materials may leak if not properly installed. Tubular-sleeve insulation is designed specifically for pipe insulation, and it is available in a variety of sizes. Pipe insulation does not stick to pipes, thus duct tape is needed to secure the insulation.
Wrap the insulation around the pipes. Once in position, secure it by wrapping two layers of duct tape around the seams where once piece of insulation meets another. Make sure to completely wrap corners in duct tape to ensure a snug fit.