In systems where the sole water supply is through a backflow preventer and/or PRVs, the main drain test downstream of the device shall be conducted on a ______ basis.

In systems where the sole water supply is through a backflow preventer and/or PRVs, the main drain test downstream of the device shall be conducted on a ______ basis.

• A. Daily
• B. Weekly
• C. Annually
• D. Quarterly

Answer: (D)

When the only water supply goes through a backflow preventer or PRV, checking the downstream main drain becomes a critical, regular maintenance task. The drain must be able to release water (and air) properly during testing and normal operation; if it’s blocked or leaking, pressure can’t be relieved and the device may not function correctly, compromising safety. Testing the main drain on a quarterly basis provides timely, practical checks to catch developing blockages or drain faults without being overly burdensome. Daily or weekly checks are unnecessary for a drain path, and annual checks can miss problems that develop between inspections. Quarterly strikes a balance, ensuring the system remains safe and operable.

When the only water supply goes through a backflow preventer or PRV, checking the downstream main drain becomes a critical, regular maintenance task. The drain must be able to release water (and air) properly during testing and normal operation; if it’s blocked or leaking, pressure can’t be relieved and the device may not function correctly, compromising safety.

Testing the main drain on a quarterly basis provides timely, practical checks to catch developing blockages or drain faults without being overly burdensome. Daily or weekly checks are unnecessary for a drain path, and annual checks can miss problems that develop between inspections. Quarterly strikes a balance, ensuring the system remains safe and operable.