My Worcester 24i goes off after a few minutes both in hot water and heating mode.Some times it comes bock on after a while. Some days it works perfectly. I have checked the electric to the fan pump pressure switch etc and all is ok. I fitted a new pressure switch.
Just having the same problem with mine and my plumber thinks this is down to limescale. There are many options for different things that you can fit to the pipes to reduce the limescale as well as getting somebody in to do a powerflush? not sure if that helps
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