CTC water heater causes banging or knocking in pipes when turning on or off

Safety first: Ensure pipes are cool enough to touch before working near them.

Steps to check:

• Inspect visible hot and cold water lines near the heater for loose supports; secure with proper clamps.
• If your system has a check valve or pressure reducing valve, install or service a thermal expansion tank on the cold inlet.
• Install water hammer arrestors near fast-closing fixtures like dishwashers and washing machines.