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4X”- 6” Deringer 20/30 Maintenance Instructions
BD-INST-02030 | Rev C | 12/22/2015 | Copyright 2011 Backflow Direct, LLC
Open Shut-Off Valves to make Backflow Preventer Functional
1. Slowly rotate the Number 1 Shut-Off Valve Operation
Handle (A) counterclockwise to the open position. (Shut-Off
Valve is open when yellow/orange position indicator flags
are parallel to the mainline water flow)
2. Slowly rotate the Number 2 Shut-Off Valve Operation
Handle (B) counterclockwise to the open position.
Note: Yellow/Orange Position Indicator Flags must be parallel
to mainline water flow for Backflow Valve to be functional (C).
BD-INST-4X2030 | Rev A | 09/06/2019 | Copyright 2011 Backflow Direct, LLC
A
B
C
C
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