immersion heater

[bill3]

Is it cheaper to swotch an immersion heater on for ttwo hours per day (which gives enough hot water to last the day) or to leave switched on all the time and allow tthe thermostat to regulate the heat?

[hertz]

It's cheaper to use a timeswitch and have your immersion heater only switch on during the night and use off-peak electricity (Economy 7). You will need to have your tank well lagged to retain the heat. I find my heater only switches on for a total of about 2 hours via the thermostat, but we rarely run out of hot water.