immersion heaters

[sambro]

if you left it on permenantly, would it be more economical, than switching it on for an hour or so?

[vehelpfulguy]

When an immersion heater is switched on it heats the water till it reaches a certain temperature.

If it has good lagging it should stay near that temperature and only fall very slowly, maybe by a couple of degrees.

Even after the tempeature has dropped by this couple of degrees it would still be very hot.

If you left the heater on all the time it would continually be heating the water up to that top temperature, which would be a waste of money as the temperature would already be quite high.

To save money, make sure it is well lagged, and maybe drop the thermostat by a couple of degrees so it does not heat the water quite so hot.

[gucciman]

this question crops up again and again. i would say the opposite, it takes a hell of a lot of energy to heat up water from cold compared to maintaining the temp, if ur well lagged then the thermostat is only going to kick the immersion in intermittently.

[Ethel]

This site says turn it off:

http://www.eso.ed.ac.uk/Energy/FAQs.shtm

[gucciman]

i'm not going to argue with university boffins, presumably they've spent millions researching such matters!

[gucciman]

oh i will add this though, before i re-trained as a heating engineer i worked as a lab tech for a suface coatings manufacturer and part of our job was test spraying paints in spraybooths. our know it all boss told us to turn the booths off after every time we sprayed to save money but the company electrician called him a prat and said it costs far more to heat the booths up from cold everytime than it does to keep them on all day.

[Doc Spock]

Definately off till required.

I worked at Norweb for 30 years.

[beso]

The amount of heat lost from a container is proportional to the difference between the internal and external temperature. The only way the heat is replenished is the immersion element.

Clearly the longer the water is maintained at the higher temperature the more it will cost to operate.

[RAS]

Thank you for the site Ethel.
It gave answers to two questions that have rumbled around in my head my head 'on and off' so to speak for around 3 decades.

Thanks again