Black Tank Flush Vacuum Breaker
Had a major water leak today while operating the black tank flush on our 2017 Outback 325BH. After turning the water off and cleaning up the majority of the mess I went in search of the source. Turns ...
Forum Discussion
Black tank flush 'anti-siphon vacuum breaker backflow preventer' is OPEN to atmosphere around top cap.
Flush water comes in bottom, pushes a disc up which seals OPEN area and water then flows out thru side to the nozzle in tank.
When water supply is turned off, disc falls back down closing off bottom thus preventing backflow. When disc drops it also breaks any vacuum in line by exposing opening to atmosphere ---tank side
Too high of water pressure and it can leak out top
Disc not fully sealing off top area and it will leak out top
Flush water comes in bottom, pushes a disc up which seals OPEN area and water then flows out thru side to the nozzle in tank.
When water supply is turned off, disc falls back down closing off bottom thus preventing backflow. When disc drops it also breaks any vacuum in line by exposing opening to atmosphere ---tank side
Too high of water pressure and it can leak out top
Disc not fully sealing off top area and it will leak out top
