Applicable Systems
Wilo Circulator Pump
Symptoms
The Wilo pump displays alarm W006, indicating a suction or discharge valve fault. The valve is not fully open or is malfunctioning, restricting flow or causing backflow.
Possible Causes
- Valve handwheel not fully open or actuator stuck in partial position
- Valve seat damaged or blocked by debris
- Check valve disc stuck or spring broken, preventing closure
Troubleshooting Steps
- Step 1: Verify valve position visually and by feel
Valve is fully open with the handwheel backed off or actuator at 100 percent open signal - Step 2: Listen for flow restriction noise at the valve
No excessive noise or pressure drop across the valve when fully open - Step 3: For check valves, verify proper seating when flow reverses
Check valve closes promptly when flow stops with no backflow observed
How to Reset
To reset: 1) Open the valve fully. 2) Clean or repair the valve if internals are damaged. 3) Replace faulty check valve components. 4) Restart the pump.
Source: Wilo Pump Installation and Operating Manual, Wilo SE
Category: Pump