Boiler makes loud banging or kettling noises when heating, especially as it starts or stops, pipes may vibrate.

Safety first: No immediate danger if there is no smell of gas or burning, but switch off the boiler if noises are extreme.

Homeowner checks:

• Check system pressure and top up if low.
• Bleed radiators to remove trapped air.
• Ensure all radiator valves are open to allow good circulation.

Engineer actions:

• Assess the level of scale and sludge; perform a chemical clean or powerflush as appropriate.
• Add inhibitor to the system to prevent future corrosion and scale.
• Check pump performance and replace the Worcester pump head if weak.
• In severe cases, replace the primary heat exchanger.

Addressing kettling early can extend the life of the Worcester heat exchanger and reduce gas consumption.