Backyard Backflow Assembly Mechanic

This is a 1″ Watts 009M2QT relief valve. It was tested by a certified backflow tester when it was installed and  it passed the initial test.

Some time after that and prior to the home being sold the assembly began to vent water. Most likely the builder, in his infinite wisdom, had a carpenter fix it. The odds are the technician damaged the piston O-ring upon reassembly causing water to flow through the relief valve stem vent. The technician rectified the problem by plugging the relief valve stem vent with a screw. The technician also failed to reinstall the relief valve spring. As a result he succeeded in making sure the relief valve would never open again.

This is just one reason why we test  the backflow assemblies annually.  Aside from failures due to normal wear and tear,  there are folks out there who think  they are doing the right thing  by modifying an assembly  in an attempt to repair it.  These modifications reduced a high hazard protection backflow assembly,  to a low hazard device, and of course this is not allowed.