Backflow Test Cocks

Oftentimes only licensed or certified professionals can conduct backflow testing and repairs. Backflow testing requires specialized training, equipment, and certification, as it involves protecting the public water supply from contamination.

A backflow test cock can typically be opened or closed using a flathead screwdriver. Most test cocks have a small slotted screw head on top that turns to open or close the port. Some larger units have tiny handles you can turn by hand.

Water coming out of a backflow test cock usually means the test port is partially open. The small slotted screw on the test cock only needs a ¼-turn to open or close, but if it’s slightly open, water can leak or spray out. It can also happen if a test gauge was recently removed, debris is stuck in the port, or the rubber seal inside the test cock is worn. In most cases, turning the screw clockwise until it’s perpendicular to the port will close it and stop the leak. If water continues to drip, the test cock may need cleaning or replacement.

If your backflow test fails, it means that your backflow prevention device isn’t protecting your water supply. Your certified tester should provide a detailed report explaining why the device failed. Review this report and schedule repairs promptly, as failing to address the issue could put your potable water supply at risk.