Boiler not switching off

[Icyblue]

I have a ten year old Classic Ideal boiler that is not manually switching off via the programmer when I press the off button. After trying a few times switching off, it is now off but I could still hear a bit of noise coming from the boiler like it is still on. The thermostat was changed half a year ago so don't think that is faulty. Any ideas?

Is it using gas? (look at the meter)

Or perhaps it is the pump (if you have a hot-water cylinder)

Or perhaps (unlikely) it is the fan, which usually starts just before it lights).

Both of these are electric motors and will stop if you turn off the electricity.

Or it might be running water that you can hear, probably from a leak, or maybe a running tap. Look at the outside wall behind the boiler. Turn off your water stopcock and see if the noise stops.

Leaks often happen from pipes in or under the floor, including radiator pipes.

Does your boiler have a pressure gauge on the front, or is there a small water cistern in the loft? Is it running?