davezawadi:
The mains voltage thermostats have a heater resistor in them to provide hysteresis, and behave rather oddly when just powered up (had one last week). If the boiler expected a LV electronic one I expect that it would not work at all. I doubt that you have damaged anything, its just one of those things, and may not have worked correctly for some time (thus the "thumping the thermostat"). I doubt that there is an additional fuse in the boiler.
davezawadi:
The mains voltage thermostats have a heater resistor in them to provide hysteresis, and behave rather oddly when just powered up (had one last week). If the boiler expected a LV electronic one I expect that it would not work at all. I doubt that you have damaged anything, its just one of those things, and may not have worked correctly for some time (thus the "thumping the thermostat"). I doubt that there is an additional fuse in the boiler.
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