24/7 ??

[poshman]

hi all, i have fitted an immersion heater with the help from this site...
some people say that it dosent cost anymore if you just leave the immersion on 24/7 as it just cuts off when it reaches temp, i understand the theory but i just dont believe it..... what are your expert views on this subect.. thanks P M

 

[breezer]

try it and see

the theory is as you said if water is at or close to temp then heater will only be on for short while, but if water is cold, it has to be on for a long while

 

[plugwash]

the cooler the water in the tank the lower the losses.

the heater heats water you use and provided heat for the losses.

so it will use more power if you leave it on, how much more depends on the situation (e.g. do you use the same amount of hot water or less if the waters hotter and is your tank well insulated).

most domestic immersion heaters are 3KW so you should be able to use a plug in power meter on them if you replace the switch with a plug and socket.

also if you have economy 7 then you will wan't to take advantage of the cheap rate leccy.

 

[mapj1]

Unless the tank is pretty much perfectly lagged = does it feel cold to the touch?
then there will be losses, and rather than heat up against the losses with the heater cycling on and off whiel you are not using it, it is better off..
If you live a regular routine then it might well be best to time switch it so it comes on an hour or so before you will need it.

I added a double jacket to mine, and it still cools down over about 5-6 hrs from 70 deg to lukewarm , so I wait for the economy 7 burn before I get a bath, and dont bother with the very early morning heat up.

 

[securespark]

Of course, the dung hits the ventilation device when the stat fails, and your tank boils ad infinitum!

 

[Steve]

Is it possible to get a "intelligent" thermostat that keeps the water at, say, 30-40 degrees all the time, and at set intervals (bath time, 1st thing in the morning) heats it up to 60 degrees?

 

[Stoday]

a plug in power meter on them if you replace the switch with a plug and socket.

You can get a plug in power meter for less than £5 on special offer this week:
http://www.lidl.co.uk/gb/index.nsf/pages/c.o.oow.20050725.p.Energy_Monitor