My wall mounted Baxi which heats radiators and, via a coil in the copper cylinder hot water, started kettling last year. Not bad enough to thump/bang still less cut out, but definitely sounded as though it was on the cusp of boiling. Turned it down a notch and it's been OK since.
In the past we've had full on bang/boil/cut out scenario. The first was due to a blockage of iron oxides stopping the header tank keeping the system full. The second was a fault on the boiler where it wasn't calling the pump on when it fired - dry solder on a circuit board.
Worth checking for other things as well a sludge/scale.
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Central heating boiler kettling 
Central heating boiler kettling