Softener bypass valve is difficult to turn or leaks when moved between service and bypass

Safety first: Depressurize the system by shutting off the main water and opening a faucet before removing the bypass.

Step-by-step checks:

• 1. Exercise the bypass: Gently move the Marlo bypass between service and bypass several times to loosen minor buildup. Do not force it.
• 2. Inspect for leaks: Observe all bypass joints and seals while slowly pressurizing the system.
• 3. Remove and service bypass: If still stiff or leaking, remove the bypass from the valve. Disassemble according to Marlo instructions, clean internal parts, and inspect O-rings.
• 4. Lubricate seals: Apply NSF-approved silicone grease to O-rings and sliding surfaces before reassembly.

When to replace parts: Replace the Marlo bypass valve assembly or bypass seal kit if cracks or severe wear are found.