All depends on your system. If you have a tank thermostat then it will only fire up your boiler when you need the water heating. If not then every so often it will fire up and circulate and if it is already hot switch off again. The name boiler is maybe wrong they do not boil water there is a sensor inside which limits the water temperature.
so in effect, to put my hot water onto constant would be cheaper than running the immersion and save all the medling with the system by changing or adding timers and such? thanks ________ medical marijuana dispensaries