Thanks for the suggestions
Hasn't been changed since we moved in two years ago. It did this once a while back. The thing that. Can't get my head round is that it's not tripping anything the circuit is still complete to get it back working it's a fused switch next to the boiler I click off and...
forgive the basic errors I'm not an expert on any of this. We have a hot water tank and gas central heating it is controlled by a dial thermostat and a Honeywell st699. The one day two cycle one...
If the system calls for hot water OR central heating then there is no issue and it works fine...