Solenoid valves are among the most reliable components in a pneumatic system, and among the most common causes of an unexpected stop. The gap between those two statements is maintenance.

Why solenoid valves fail

• Contaminated air – dirt, water and oil carry-over scour seats and jam the armature
• Coil burnout – wrong voltage, sustained over-voltage, or a coil energised continuously in a duty class not rated for it
• Seal degradation – incompatible media or elevated temperature hardening the elastomer
• Wear – normal cycle life exhausted, usually faster on high-cycle machines

Weekly checks

• Listen for a sluggish or double-clicking actuation
• Check for air escaping from the exhaust port when the valve is closed
• Confirm the coil is not hot beyond its rated class
• Verify supply pressure is stable at the valve inlet

Monthly checks

• Drain filters and confirm the auto-drain is functioning
• Test manual override operation on critical valves
• Inspect coil connectors and terminal tightness for heat discolouration
• Log cycle counts on high-duty valves to plan replacement

Annual service

• Replace filter elements, not just clean them
• Inspect and replace seals on valves in continuous duty
• Verify response time against the original specification
• Review the spare parts holding against actual consumption

Common mistakes

Two errors account for most premature failures. The first is treating air treatment as optional — a valve downstream of a saturated filter will fail regardless of its quality. The second is replacing a failed valve without diagnosing why it failed, so the replacement fails the same way.

Spares strategy

Hold one spare for every valve that stops the line, and hold coil and seal kits separately. On high-cycle machines, planned replacement at the manufacturer’s rated cycle count is cheaper than reacting to a failure.

If you need help building a critical spares list or identifying the correct replacement for an obsolete valve, our team can review your installation.