OPERATION
1. Do not permit the use or operation of any valve at pressures above the rated pressure of the valve.
2. Stop the actuator before the valve is fully opened or closed against stops, and complete the operation manually. Be sure to
check the actuator directional switch against the direction indicated on wrench nut, handwheel.
3. If a valve is stuck in some intermediate position between open and closed, check fi rst for jamming in the actuator. If nothing
is found, the interference is inside the valve. In this case, do not attempt to force the disc open or closed, because excessive
torque in this position can severely damage internal parts.
MAINTENANCE
Maintenance of rubber-seated butterfl y valves by the owner is generally limited to actuators and shaft seals. In some instances,
valve design permits fi eld adjustment when leakage occurs past the disc. Unless the owner has skilled personnel and proper
equipment, any major internal problem will probably require the removal of the valve from the line and its return to the manufac-
turer for repair.
1. Normal maintenance is in the area of shaft seals and actuators. Seal leakage, broken parts, hard operation, and in some
cases, seat leakage should be corrected by a repair crew as soon as possible after a defect is reported.
2. If repairs are to be made in the fi eld, repair crews should take a full complement of spare parts to the job site. Be sure to
review the valve-manufacturer’s drawings prior to any repair work.
3. Provisions should be made to shop line fl ow and isolate the valve from line pressure prior to performing any corrective main-
tenance.
4. After completing repairs, cycle the valve through one complete operating cycle and, after line pressure has been restored,
inspect for leakage.
5. If major repairs require the removal of the valve for repair, be sure to notify all interested parties in the water department and
fi re department that the valve and line are out of service, On completion of repair and re-installation, notify the same personnel
of the return of the valve and line to service.
Summary of Contents for 3900F Series
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