Timer on Economy 7 immersion. help needed?

Legacy_user

Hi, just wondering if anyone can help.

I am on economy 7, with what I belive to be a direct electric immersion heater. there are two elements to it, one half way up and one at the bottom.

The top element is attached to an any time switch and the bottom to a night time only one none of which have timers.

My question is how quickly does the overnight element heat the water, can I fit the timer to both switches so it is only on for an hour or so overnight or does it need longer?

I have no idear what i am talking about regarding this just looking for advice before undertaking any work.

Thanks

UtilityMan_3

The bottom element will heat water to the required temperature during the night in the off peak (cheaper) period, and keep it to that temperature. It switches off when the temp is met, and switches off when the night rate is over (the time switch varies due to BST etc).

The top one only heats the top, and is for you to use as and when needed. i.e. switch on and off when you want more hot water.It saves energy as it only heats the top portion rather than the whole cylinder.

That's what it is designed for and therefore best left alone, in my opinion.

mute_posting

Pretty much agree with #2

Only thing I'd add is make sure the thermostats are set correctly (about 65 deg C) so you aren't heating water too much (wasting energy) or not enough thus requiring you to "boost" the top half of the tank at expensive peak-rate to get usable temperature hot water.

I doubt it would take more than about 4 hours to heat a whole tank of water from cold (obviously depends how big tank is and how cold water starts and finishes at!) or about an hour or two to heat a partially cooled/used tank.

As UtilityMan says, leave the bottom heater to do it's own thing off-peak (controlled by the thermostat) and only use the top one if you run out of water or it is too cold for requirements.

HTH

MP