Ytc YT-320, Product Manual

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YT-320 / 325 series
4. Maintenance
4.1 YT-320/325 requires regular maintenance. Please refer to below repair kit part list. It is
suggested to replace all three parts at the same time to guarantee the life cycle of the
product.

Upper diaphragm assembly: 1 each

Lower diaphragm: 1 each

O-rings: 2 each
5. Trouble-Shooting
Please follow trouble-shooting when the product is not functioning properly.

No valve response to signal to a positioner.

Please check if supply pressure is stable from regulator to positioner and/or to
volume booster.

Please check if air pressure is being exhausted from positioner’s exhaust port.

Please check if signal and exhaust ports of the volume booster are being cleared.

Unstable valve operation when signal has been sent to a positioner.

Please reduce valve packing and/or valve friction level.

Please check current actuator size and check if volume booster size is suitable.

Hunting occurs when signal has been sent to a positioner.

Please reduce valve packing and/or valve friction level.

Please check current actuator size and check if volume booster size is suitable.

Please turn adjust screw counter-clockwise to reduce sensitivity.

Slow valve operation after installing a volume booster.

Please check if regulator pressure is too low.

Please check if supply piping to the actuator has been blocked or clogged.

Please check if there is any leakage.

Please turn adjust screw clockwise to enhance sensitivity.