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MAINTENANCE AND INSPECTION
The AVK Series 41 Check Valve requires no scheduled lubrication or maintenance. The valve can be serviced or
inspected without removal of the valve body from the line.
INSPECTION:
If inspection of the valve is required, follow the
DISASSEMBLY FOR INSPECTION Instructions.
TROUBLESHOOTING:
WARNING:
The line must be isolated, depressurized, and drained before removing the valve bonnet or removing the
valve from line. Failure to do so may cause pressure to be released resulting in severe injury or death.
Several problems and solutions are presented below to assist you in troubleshooting the valve.
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Leakage at the shaft bushings ( Open Bushing (417), Closed Bushing (422) ) : Ensure that the shaft
bushings are properly tightened to 45-ft-lbs. If leakage persists replace the Inner and Outer Bushing
O-rings, (418,429) with an AVK Series 41 seal replacement kit.
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Leakage at the Bonnet: Ensure that the bonnet bolts are tightened to 45-ft;lbs. If leakage persists, replace
bonnet gasket (412).
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Valve leaks when closed: Remove and inspect disc for damage. Replace if necessary. Ensure that the
sealing surface in the valve body is clean and undamaged. NOTE: Per the AWWA C508 standard
for swing check valves, bronze seated valves do not seal drop tight.
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Valve does not open or close: Verify operating pressure is high enough to open the valve. Disassemble the
valve to check for an obstruction in the valve or pipeline.
