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Residual power to coil |
- Lift coil slightly to check if magnetic field is present.
- Do not completely remove coil if energised as IT WILL BURN OUT.
- Check wiring and diagram
- Check lead connections.
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Dirt ingress in pilot hole under coil armature |
Clean orifice with pin or compressed air. |
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Manual over ride |
Check position of manual over ride and adjust if required. |
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Pressure pulse upstream.
Pressure difference in/out too high
Outlet pressure occasionally higher than inlet pressure |
Check valve technical data in solenoid-valve catalogue and replace if necessary.
Check pressure and flow
Check other items in installation. |
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Damaged or bent armature tube |
Replace tube. See spare parts available in solenoid-valve catalogue |
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Damaged diaphragm base or valve seat |
- Replace valve.
- Check valve is being used within specification in solenoid-valve catalogue.
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Diaphragm inverted |
Refit diaphragm correctly or replace with new part. See valve spares in solenoid-valve catalogue. |
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Dirt ingress in armature tube |
Clean valve armature or replace. If hard water scale build up install water softener or dry armature valve from solenoid-valve catalogue. |
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Corrosion in pilot orifice |
- Replace damaged components.
- Check valve specification in suitable for application, see solenoid-valve catalogue.
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Valve installed wrong way around |
Check flow direction is in line with flow direction arrow or in/out markings on ports. |
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Missing components after maintenance |
Replace parts according to spares listing as per solenoid-valve catalogue. |
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Valve Noise Appears Incorrect |
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Buzz |
- 50 or 60Hz AC buzz. Use DC valve with rectified connector.
- See connector’s section in solenoid-valve catalogue.
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Water hammer when valve opens |
- Caused by high liquid velocity and high pressure through small pipe bore.
- Install a closed vertical T piece pipe in before the valve to trap an air pocket to dampen noise.
- Reduce inlet pressure.
- Increase pipe size to reduce velocity.
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Water hammer when valve closes |
- Caused by high liquid velocity and high pressure through small pipe bore.
- Ask supplier to reduce closing time of valve. This can be done carefully by increasing slightly (10-20%) the size of the pilot pressure equalising hole in the diaphragm. Too much and valve will not open.
- Reduce inlet pressure
- Increase pipe size to reduce velocity.
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Difference in inlet/ outlet pressure too high or pulsating pressure line |
- Check valve specification in solenoid-valve catalogue. Check pressure and flow.
- Check solenoid-valve catalogue for more suitable valve for application.
- Check other items in installation.
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