BoilerBuying Guide2026-03-10
Noisy Boiler? Common Causes by Sound
Kettling means scale; gurgling means air; banging means delayed ignition — each has a fix.
Different boiler noises point to different problems. Here's a quick sound guide.
Kettling and gurgling
A whistling kettle sound means scale or sludge; gurgling means trapped air or low pressure.
Banging and humming
A bang on ignition suggests delayed ignition (a safety item); humming or vibration points to the pump.
Key takeaways
- Kettling = scale/sludge
- Gurgling = air or low pressure
- Banging = delayed ignition
- Humming = pump
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