Imersion Heater

I have been reccomended this site to get the answer to my question, hope you guys can help.

Can you tell me if my imersion heater that I have to turn on and off manually as needed should be left on permanently?
I have spoken to several plumbers and they are coming up with different answers.

I have been told it would be cheaper for me to leave it on indefinately, as the thermastat will cut out when the water reaches a certain temprature, rather the keep switching it on and off thus heating the water up from cold.

Your views please.

(Do not advise me to get a timer fixed. I do know this, and it will be happening eventually anyway).

When i was at college doing my city and guilds we looked into this in some depth and came up with the conclusion that it was best to leave it on all the time if you are using the hot water every day

i cant remember all the ins and outs because it was 15 years ago but hope that helps you

It should be obvious that leaving it on continually is a little more expensive. perhaps 20%. It also depends how well insulated your cylinder is. It also causes more wear on the parts.

It depends on your HW needs. If you are at home most of the time then leave it on.

If you are away much of the time leave it on when you are there and off when away.

Tony