Solenoid Valve making unusual/unexpected noise?

By Admin on Fri 12 May 2017 in Troubleshooting

A quick and simple guide to troubleshooting your solenoid valve. The possible causes for your solenoid valve making noises are listed below alongside instructions of how to resolve the issue.

Chatter or buzz sound when energised.

  • Remove power from the coil.
  • Inspect the plunger and sleeve for excessive wear or contamination.

Solenoid valve buzz

  • A solenoid buzz at 50Hz or 60Hz is a sign that an AC is being applied to the solenoid valve and the armature is either restricted, without a copper shading ring or an incorrect AC voltage has been applied.
  • Install a DC solenoid valve coil and supply a DC voltage.

Water hammer/pipe bang when solenoid valve opens   

  • Caused by high water or liquid velocity (speed) typically a high pressure through a small bore.
  • Install an anti water hammer device or install a vertical blanked ended pipe with air pocket to absorb water pressure shock waves.
  • Reduce inlet pressure.
  • Increase pipe size to reduce velocity (speed) of ravelling media.

Water hammer/pipe bang when solenoid valve closes.    

  • Caused by high velocity (speed) liquid media and high pressure through small pipe or valve bore.
  • Ask the supplier to reduce closing time of solenoid valve. This is achievable by carefully increasing the pilot hole in the diaphragm by 10-20% but this hole must remain smaller than the centre hole otherwise the solenoid valve will not close.
  •  Reduce inlet pressure.
  • Increase pipe size to reduce or slow down media velocity (speed).

Differential pressure too high or pulsating pressures in line.    

  •  Check solenoid valve specification meets the requirements of the system. Pressure assisted or servo assisted solenoid valves require a stable minimum pressure difference between inlet and outlet. If a pressure assisted valve is over sized or incorrectly specified when the valve opens the downstream back pressure will cause the valve to momentarily close until the back pressure drops and then the solenoid valve will open again and the cycle will repeat.
  • Check other valves in the installation.