Normal air leakage doubles when a central air conditioner is running. This is caused by pressure and suction created in the air conditioner and the ductwork. Consequently, you need to reduce or eliminate air leakage as it can account for 10 to 30 % of the cooling load. Leakage is commonly found around:
- Electrical service boxes
- Plumbing infiltrations (kitchen and bathroom)
- Fireplaces and chimneys
- Heating and air conditioning ducts
- Light fixtures
- Attic access doors
Caulk and weather-strip around all doors, windows, and other openings.