| Failure | Cause | Troubleshooting method |
| Valve does not move | Positioner, with air supply and signal, but no output | The positive and negative poles of the signal are reversed | Correct wiring |
| The constant orifice of the amplifier in the positioner is blocked | Remove dirt |
| The moisture in the compressed air collects in the amplifier | Clear and dry air supply |
| Signal but still no action | Trims and seat are stuck | Remove and replace parts |
| Trims and cone pin fall off | Connect the taper pin |
| Actuator failure (such as air leakage in the cylinder) | Replace O -ring |
| Under conditions of high temperature shut tight, made into jam | Disassemble the valve, clean, grind and reassemble |
| Valve operation is unstable | The air supply and signal pressure are normal, but the control valve is still inactive | Positioner failure (refer to the positioner manual) | Repair according to the locator manual |
| Leakage in output pipeline | Overhaul pipeline |
| Actuator output torque | Replace the actuator |
| Excessive vibration | Vibration when the control valve is close to the fully closed position | The control valve is selected too large and often works at a small opening | Recalculate the diameter of the smaller valve seat |
| Wrongly selected flow closed type, normal flow open type should be selected | Change the installation direction |
| The control valve vibrates at any opening | Unstable pipe support | Additional support for the control valve |
| Vibration source nearby | Eliminate vibration sources |
| System resonance | Change the valve to change the frequency to eliminate resonance |
| Sluggish valve action | Sluggish reciprocating stroke | The valve body has a large viscous medium coke clogging phenomenon | Cleaning |
| Packing is too tight | Relax filler |
| Sluggish action on intake | Cylinder leaks or pipeline leaks | Repair or replace parts |
| Large valve leakage | Large leakage after closing in place | The sealing surface of the valve core and seat is scratched by impurities in the pipeline | Repair or replace parts |
| Trims or seat displacement is not tight | Adjust the valve core or valve seat position and tighten |
| The trims cannot be closed in place | The position of the limit screw at both ends of the cylinder is wrong, so that the valve core is not closed in place; the position of the hand wheel is incorrect | Adjust the limit screw; screw in and then unscrew the handwheel screw, adjust the handwheel |
| The pre-pressure of the air opening valve spring is insufficient or the air supply pressure of the air closing valve is too high | Increase spring pre-pressure or increase air supply pressure |
| There is a hard object stuck in the valve cavity | Remove foreign objects |
| Severe kick when opening the valve | Closed off and on open jump serious weight | Flow closed type; trims closed too tightly | Turn the 180 °mounting plate to flow open type |
| The input pressure is too low when the positioner air valve is 4mA | Increase the starting point output pressure |
| Not proportional | The valve is fully open or fully closed when the signal changes | Loose connection between the positioner and the cylinder shaft, forming a straight-through connection that cannot be adjusted | Reconnect and tighten |
| Leakage in packing and joints | Leakage at the packing seal | Packing is not compressed | Packing packing |
| Leakage at the high pressure valve lens pad | The temperature or stress changes cause the nut to loosen | Tighten the nut |
