Air Conditioning Causes Washing Machine to Leak

How an Air Conditioner Works

• Air conditioners work by pulling in indoor air and blowing it across cold copper coils filled with refrigerant. This refrigerant absorbs the heat in the air, reducing the air's temperature. The coils "sweat" humidity in the air in the form of condensation. The waste heat and condensation water are pumped outside the home while the air is recirculated to the house, cooler and dryer than it was when it entered the system.

Condensation

• An air conditioner running in a humid climate can produce a significant amount of condensation in the course of a day. This water is pumped from a condensation pan located under the refrigerant coils in the air handler to a drain or location outside your home. Many municipalities do not allow air conditioner condensation to be drained directly into the sanitary sewer system, but this often does not stop air conditioning installation contractors from doing so. An air conditioner condensation drain connected to your sewer or waste pipe at the washing machine may be the cause of your washing machine leak problem.

Washing Machine Standpipe

• The washing machine standpipe is a tall vertical pipe that the machine drains its waste water into. Typically the drain line on the washing machine slides inside the standpipe, leaving room on either side for air to escape. This makes the standpipe an easy, if illegal, site for draining a washing machine condensation line.

The Leak

• A washing machine that leaks only when the air conditioner is on is likely suffering from a clogged standpipe. The condensation drain from the air conditioner is tied in to the washing machine drain and is likely causing an overflow. Remove the condensation drain from the standpipe or washing machine drain and clear out any lint or debris clogs. Consider relocating the condensation drain line to floor drain or outside the home, depending on local municipal building codes.