Emerson Vilter VSS - Section 4: Operation; Stop;Check Valve Operation

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Section 4 • Operation
VSS/VSM/VSH/VSSH • Installation, Operation and Maintenance Manual • Emerson • 35391SD
Stop/Check Valve Operation
1
1 Doesn´t apply to: VSM-97, VSM-113, VSM-127
Closed:
In the manually “Closed Position”, the stop check is operat-
ing as a conventional stop valve, not allowing ow in either
direction.
Valve Size 1.5” 2” 2.5” 3” 4” 5” 6” 8”
Number of Turns Open
(From Closed Position)
2 2.25 2.75 3.25 4.5 3.75 5.75 7.75
Auto:
In the “Auto Position”, the stop valve is operating as a check
valve, allowing ow in the directions of the arrows.
To set the valve to the automatic position, fully close the
valve, and turn the stem out as indicated by the chart below.
Open:
In the manually ” Open Position”, with the valve stem fully
back seated, the valve disc is lifted slightly, allowing ow in
either direction.
Table 4-2. Stop/Check Valve Open Positions