Your home’s AC and plumbing are closely related at a specific point. An air conditioner actually performs two vital functions to keep your home comfortable. First, it extracts heat energy from indoor air to cool the house. In addition, the air conditioner condenses water from the air to reduce indoor humidity. Lowering humidity makes the air conditioner cool more effectively and the house feel more comfortable. Here’s how water and its associated plumbing figures into the cooling process, accounting for the link between AC and plumbing.

  • Warm indoor air is pulled through the HVAC return ductwork and into the evaporator coil inside the indoor air handler. The evaporator circulates frigid refrigerant vapor, rapidly reducing the temperature of airflow through the coil and causing humidity to condense out of the air.   
  • On a hot, humid day, the evaporator coil may produce as much as 20 gallons of water. This liquid collects in the condensate drain pan, which is typically located on the floor beneath the indoor air handler.  
  • Water entering the drain pan rapidly flows back out through the condensate drain line (typically a white PVC pipe). This usually extends through an exterior wall, and the condensate water is dispersed into the ground next to the house. In other cases, the condensate drain line may connect instead to the home’s plumbing drain system instead.

As long as the relationship between AC and plumbing works properly, the process continues without incident. However, a certain scenario may cause water damage.

  • Algae or mold growth occurring in the condensate drain pan may clog the drain line. As the AC cycles on and off, the pan will overflow repeatedly, and considerable water damage inside the house may occur before it is noticed.
  • Annual preventive maintenance by a qualified HVAC service technician typically includes inspection, cleaning, and disinfecting the drain pan and drain line to prevent clogs and overflow.
  • Alternatively, a float switch can be installed inside the drain pan to shut off the air conditioner before damaging overflow occurs.

For more about the relationship between your home’s AC and plumbing, talk to the professionals at Mowery Heating, Cooling and Plumbing.