I am sure most of you have noticed the little (usually) chrome cap mounted on the kitchen sink or counter-top----the dishwasher air gap device.  This device is designed to prevent dirty water from being sucked back into the dishwasher which would obviously create an "unhealthy" condition.  While some of the newer dishwashers have "built-in" air gap devices, many jurisdictions require that there be a one built permanently into the drain.  This picture shows what a typical counter-top air gap device looks like---but the drain lines have been hooked up backwards and the device acts like a fountain when the dishwasher drains.  Interesting---but still wrong.  If you see water or suds coming out of the air gap device consult a plumber for repairs.

     Another type of air gap device for the dishwasher is called a Johnson-"T" and consists of a device that is built into the wall cavity and has a venting cap at the exterior of the home.  Some people don't like the looks of the counter-top/sink devices so they opt to have a Johnson-T installed instead.  There are two common problems with the Johnson-T's.  One is that the cap gets painted over which plugs the holes rendering the device non-functional.

     The second common problem is that the original test cap (from when the plumbing was installed) is still in place---again rendering the device non-functional.  The holes of the painted ones can easily be drilled out to make it functional again and the capped ones can either have a proper cap installed or the test cap can have several small holes drilled in by the plumber to make the device functional.

 Charles Buell

www.buellinspections.com