If there is water leaking around your furnace when your air conditioner is running, you probably have a clog in your drain line or a hole in your drain pan. It is normal for water to collect (condensation from your air conditioner dehumidifying your home’s air), but the water should be draining outside your home through a drain line.

Make sure you get the leak fixed promptly as even a small leak can cause water damage or lead to mold and mildew growth.