Page 11 of 12
Copyright © AVK Holding A/S, original version, rev. 1, 8-July-2021
should be within the production test pressure for the valve.
The maximum permissible flow velocity is according to EN1074-1.
If the limits of use specified in these instructions are exceeded or if the valve is used on
applications for which it was not designed, a potential hazard could result.
9. Operation and Maintenance
9.1 Operation
the Pressure Sustaining/Relief Valve
Pull PSV regulator 3 to unlock and turn clockwise slowly to increase the upstream set pressure,
turn anticlockwise slowly to decrease the upstream set pressure, then push the PSV regulator 3
to lock again.
9.2 Maintenance
Other than ensuring all bolts and studs are secured, no routine maintenance is required as long
as the valve operates satisfying. If the valve ceases to function the internals can be inspected by
disassembling the pilot valve and removal of the bonnet and if necessary, the valve should be
removed from the line.
WARNING:
Prior to any maintenance work that requires disassembly make sure that the
pressurized line involved is isolated, depressurized and drained before starting any disassembly.
Failure to do so may result in sudden pressure release and subsequent severe injury or death.
9.3 Repair of valve
If the valve is not functioning as intended it may be necessary to take it apart for repair.
9.3.1 Replace the pilot valve
Close both upstream and downstream isolation valve (A, E), and close both ball valve (1,2) and
needle valve 4, replace the pilot valve 3 with a new one.
9.3.2 Replace the filter
Close both upstream and downstream isolation valve (A, E), and close both ball valve (1,2) and
needle valve 4, remove the filter 6 and replace it with a new one.
