Why Does My Boiler Make a Banging or Kettling Noise?
CANRO Heating & Cooling provides expert advice on this common question for homeowners in Greater Vancouver. If you need professional service, our licensed technicians are available across the region.
When to Call a Professional for Help
While understanding the answer to this question is helpful, some situations require professional expertise. If you are uncertain about any step, if the problem recurs, or if you notice any signs of gas odour, carbon monoxide, or electrical hazards, contact CANRO Heating & Cooling immediately. Our licensed technicians across Greater Vancouver can provide expert diagnosis and repair. We recommend professional service for any issue that involves gas, electrical components, or safety-critical systems.
Related Services from CANRO
CANRO Heating & Cooling provides comprehensive boiler service across Greater Vancouver, including diagnostic inspections, emergency repairs, scheduled maintenance, and system replacement. Our Red Seal certified technicians service all major brands and carry OEM parts in their vehicles. For emergency service related to this question, call (604) 359-1081.
Answer: Why Does My Boiler Make a Banging or Kettling Noise?
A banging, rumbling, or whistling noise from your boiler — often called "kettling" — is usually caused by limescale buildup on the heat exchanger. When hard water is heated, minerals precipitate out and form a layer of scale that insulates the heat exchanger. Water trapped underneath the scale overheats rapidly, creating steam bubbles that collapse with a banging sound (similar to a kettle boiling). This is most common in areas with hard water and in older boilers. Kettling reduces efficiency and can eventually cause heat exchanger failure. Professional descaling or heat exchanger replacement may be needed.
Safety Reminder
If you smell gas, suspect carbon monoxide or believe there is an immediate danger, leave the property and contact emergency services or the appropriate gas emergency authority. Do not remain inside — exit the building immediately and call for help from outside.