water heaters

gypsyjanet

Can someone please settle an argument for a friend of mine. Is it cheaper to keep your hot water immersion heater on all the time or to turn it off and on as you need it?

daveyjp

It depends how much hot water you are using.

I don't have a continual hot water boiler at home for the few cups of coffee I drink, but in offices they are useful as it is more efficient than boiling a kettle 50 times a day.

grahamc2003

gypsyjanet wrote: »

Can someone please settle an argument for a friend of mine. Is it cheaper to keep your hot water immersion heater on all the time or to turn it off and on as you need it?

It is always cheaper to turn it on and off as needed.

rogerblack

It always saves money turning it off. (assuming you're on a constant electricity rate)

Yes, it takes power to get it 'up to temperature' - by heating the water.
But this is the exact same amount of power released by the water as it cools down.

You save power by the water in the hot water tank being at a lower temperature for a period, and the heat loss through the walls being smaller.