Pump runs but makes a clicking or knocking noise once per revolution

Safety first: Turn off power and close valves before dismantling the pump.

• Inspect strainer and suction: Remove any debris that could be entering the pump.
• Disassemble wet end: Remove the motor from the pump housing and inspect the impeller and diffuser. Look for foreign objects or damage.
• Tighten impeller: Ensure the impeller is securely threaded or fastened to the motor shaft as per Lowara design.
• Replace damaged parts: Replace any cracked impeller or diffuser with genuine Lowara parts.
• Reassemble and test: Re‑prime and run the pump, listening for any remaining noise.