A number of things can cause water dripping from the furnace. Water dripping from the drain hose during the cooling cycle is normal and should not be anything that concerns you. If water is dripping from the furnace from anywhere other than your drain hose you may have one or more of the following problems: dirty coil, refrigerant leak, cracked drain pan, or clogged drain pipe.
A dirty evaporator coil can be caused by failing to use a quality filter or running your system without a filter. If the coil is extremely dirty, the air flow can be obstructed, causing the coils to freeze and create ice. This ice melting creates more water than the pan is designed to hold and drain, causing overflow water to leak down into the furnace.
A refrigerant leak can form within the refrigerant lines, at solder joints, or at refrigerant valves. If the amount of refrigerant is too low for your system, it will cause the coils to begin to freeze and create ice. As this melts it will not drain as it normally does. The water will run down the sides of the casing and possibly bypass the drain pan altogether.
A crack in the drain pan will cause water drainage to leak through the crack into the furnace housing. This can cause damage to the circuit board and motor inside of the furnace.
A clogged drain hose or piping is one of the easiest fixes and is caught at regular maintenance appointments. Water is designed to drain through this hose, but mold, dirt, bugs and rust can clog this drain line over time. If the drain line becomes clogged, water will back up into the drain pan and leak down the sides into the furnace hosing.
If you see water leaking, shut the air conditioner off immediately and call Fresh Air in order to prevent damage to flooring, furniture, and other items in your closet or basement. Ask about our wet switches or audible water alarms.