Vermeer McLaughlin V25, Operator And Maintenance Manual

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50-2 Operating the Vacuum Excavator V25/VX30G/VSK25/VSK30G Vacuum Excavators
Pressure Relief Valve
Units equipped with a Reverse Flow Control valve include a Pressure Relief valve
(1), preset to relieve positive system pressure at 2500 psi (173 bar).
Vacuum Relief Valve
The system includes a Vacuum Relief valve (1) preset to relieve vacuum (negative)
system pressure at 13" HG standard, or 15" HG for high altitude conditions, with a
tolerance of +/- 1" HG.
On units equipped with a manual spoil tank door, the whistling sound emitted when
the relief valve opens indicates that it is safe to unlock the door.
1
1