Installing a timer on an immersion heater.

[hugoagogo]

There is an immersion heater in the place we rent, it's on or it's off.
Landlord is unlikely to pay for anything, do you think it would be worth it to have an electrician fit a timer?
We are on economy 7 obviously not taking full advantage of it as we don't switch it on over night.
Any advice appreciated.

Is it hard wired or plugged in? Many years ago I used a plug in timer switch on an immersion.

Sadly no plug, just a switch. In fact weirdly 2 switches, one in the cupboard with the tank and one on the other side of the wall in the kitchen.
This second one seems to be the 'master' so even if the cupboard switch is off, if the kitchen switch is on, the immersion is on.
It's all rather alien to me, I haven't come across this kind of heating since the eightees!

If you have 2 switches you might have 2 separate immersion heaters in the tank. One near the bottom that only turns on during economy 7 hours and a second one nearer the top which you can switch on for a boost. This is how it was in the flat we lived in years ago, we just had the economy 7 switch on all the time and the tank of water was enough for us for the day.

Intriguing. I wonder how I can find out?

You should be able to see the immersion heaters sticking out of the cylinder.
Or maybe you only have 1 heater but it’s on 2 switches the one in the cupboard being economy 7 and the other the on at anytime switch.
Are there a lights on the switches? I’m sure our had a light which lit up during economy 7 hours.

We have got something called a Horstmann Economy Seven Quartz Maxistore Timer which was professionally installed.
It was set by the electrician to heat the water during the night when our electricity is cheapest .
We never touch it. It just heats our huge very well insulated tank and this provides us with more than enough hot water for the day. The only time we need to use the boost is if the children want a bath. They are all happy to have a daily shower which doesn’t use water from the hot tank.

I'm not often up between midnight and seven, I will get up early tomorrow and test it.

If it does come on between 12 and 7 presumably it won't actually be heating the water for 7 hours?

No, it will heat the water until it reaches a certain temperature and should then switch off.

Brilliant Thank you Geminio!
we may not need a timer after all! It might have been nice if this had been explained to us when we moved in.

Yes, we have two switches.
One we leave on permanently and this is the economy 7, so comes on at night and heats to the required temperature.
This is more than enough hot water for the day.
Apart from if one of has a bath.
If so, we then turn in the other switch for an hour for it to heat up immediately. Unless we know we won't need any more hot water that day when we don't bother.