I leave mine on all the time, it is in an airing cupboard in my bedroom so I leave the door open and it helps heat the room.
Question is, would I be better off turning it off and only putting it on when I need hot water (would probably forget!) or would it take as much electric to keep reheating it? Its on a timer/thermostat I think.
If you are the only person using the hot water, then typically half an hour a day is enough to provide a bathful of water and enough to do the washing up!
If the tank is well insulated (usually in a sleeve / foam insulatin) then it will retain it's heat for several hours. I'm a creature of habbit and got into a routine of turning mine on just before I got in the bath and turning it off just after - giving it about half an hour.
Immersion heaters are not terribly efficient and leaving it on all day will be costing you big time! Turn it off for 23 hours a day and within a couple of years you'll have saved enough in electricity bills to buy a nice efficient gas combi!
Because immersion heaters are thermostatically controlled it should be cheaper to leave them on all the time . A small drop in temperature means a smaller amount of electricity to bring back the temp. If you turn the heater off it will take a larger amount of electricity to re-heat again. Alternatively you could check your meter before and after trying different methods.
I don't see the logic there andres. Surely the total electricity used will be very similar, whether it is in small bursts or one long session.
Also if it is not well insulated, then best not to keep the temperature high when the hot water is not needed as this will lead to greater loss of energy.
There is no logic there because the answer is absolute tripe.
Whilst it may be true of gas heaters that you waste some energy by constantly turning things on and off (because more heat goes up the flue), this is NEVER true of electricity.
Electricity is always 100% efficient at converting the energy you pay for into heat.
I like what Muppit suggests.
I've decided to give it a go turning it off, but next time I want a bath and the water is cold I expect I will go back to leaving it on! Thanks for your replies.