Immersion heater question?

Reds-on-Sea

Hi all, my first post here, I usually lurk on the Housey forums.

I recently moved house and due to circumstances beyond my control, have been using the immersion heater to heat my hot water. Don't worry, getting a new combi-boiler v.soon. It's only been on during the night as I'm on Economy 7, but my question is, does the immersion heater still use electricity once the water tank is heated up? Does it have a sensor that cuts it off once temp is reached, and come back on when the water cools down? Or it it like an element that never switches off until you manually flip the switch to off?

Just something I was thinking about as if I forgot to switch it off one morning and went to work, I wonder whether I'd be using a whole day's electricity, or just the odd but when it comes on and tops the temp up etc?

Thanks all x

bobmedley

It depends on it's age - can you see a model number/name/ref on it? You can then check the thermostat setting to see what it's temp is set at - older heaters have different types of thermostats & failures are often due to them malfunctioning.

CLAPTON

immeresion heaters always include a thermostat which cuts off the electricity once a preset temperature is reached.

it should be obvious because otherwise the water would reach boiling point.

Reds-on-Sea

Thanks.

Well yes it is kinda obvious, but I just wanted to check that it wasn't using electricity in the times when it wasn't heating the water - kinda like 'standby' I guess. I wasn't sure if it cuts out completely, or is still in a state of 'on-ness'

CLAPTON

even where the thermostat works properly its not really a good idea to leave it on permanently.
depending upon how well the cylinder is lagged there will still be heat loss so the electricity will come back on again to reheat it unncessarially.
and of course, if the thermostat fails the water can boil and that can ptoentially be very dangerous... I would always have a time switch that turns it on and off on a planned basis.

Premier_2

Reds-on-Sea wrote: »

Thanks.

Well yes it is kinda obvious, but I just wanted to check that it wasn't using electricity in the times when it wasn't heating the water - kinda like 'standby' I guess. I wasn't sure if it cuts out completely, or is still in a state of 'on-ness'

The thermostat works like a simple on-off switch - there is no consumption when in the off mode

Reds-on-Sea

CLAPTON wrote: »

even where the thermostat works properly its not really a good idea to leave it on permanently.
depending upon how well the cylinder is lagged there will still be heat loss so the electricity will come back on again to reheat it unncessarially.
and of course, if the thermostat fails the water can boil and that can ptoentially be very dangerous... I would always have a time switch that turns it on and off on a planned basis.

planned basis lol, yes kinda, basically, my bf would get up in the middle of the night to turn it on so that we could have a hot shower in the morning and then I'd turn it off before leaving for work. Dregs of warm water used after work to do washing up etc... not ideal! One day he forgot and I had approx 10 mind of 'warming time' - it took the edge off, but brrr.

Hurrah anyways, boiler man's here today to fit a combi boiler in the loft to replace the old back boiler behind the 1970's gas fire in the lounge today - so will hopefully have fully functioning heating/water by weds. BF can then stop drinking 2 pints of milk before bed too...!