Harvey softener occasionally emits a high-pitched whine during service flow

Safety: Normal plumbing precautions apply.

• Fully open valves: Ensure all Harvey isolation valves are fully open in service mode.
• Bleed air: Run taps to purge air from the system after any plumbing work.
• Clean strainer: Remove and clean the inlet strainer to restore full bore.
• Check pressure: If mains pressure is very high, consider fitting a pressure reducing valve to reduce noise and stress on the system.

Persistent or loud whining may indicate internal valve wear and should be checked by a service engineer.