Water gets far too hot in my new place, and there's far too much of it. What to do?

Why do you leave it on overnight?

Two options...

1. Reduce the temperature setting of the thermostat on the lower tank heating element
2. Switch off the timer controller and just manually switch it on in the morning for the desired duration using the boost dial

Those timer controllers are archaic in nature and come on for a preprogrammed, non-changeable period during the early hours of the morning to take advantage of off peak rates. They also heat the whole tank whereas the boost control dial just heats the top half. If you are up anyway before 8am, then the boost control will be using off peak electricity till that time.

If you own the place, would strongly recommend changing out the timer controller for something more modern and intuitive.

this is the only relevant question/answer op

The 2 plastic round caps on the tank cover the thermostat controls. theres a screw to remove them

Then theres a dial with the temp settings in Celsius. turn with a flat instrument.

often theres a seal youre not supposed to break over the dial

Obviously isolate power before going near it

Due to risk of legionella it is advised water should be heated to at least 60 degrees. Maybe yours has been set very high though.

https://www.hse.gov.uk/healthservices/legionella.htm

Also worth double checking your electricity plan, is meter setup for day night - are you actually being charged less for this 'off peak' timer use. There's a bargain alerts thread where you can get advice on that.

Hi, I have the exact same setup.

As mentioned you have two controls you can adjust, but if you are not comfortable with electric maybe get a pro as both involve opening things up.

1. in your tank you have two elements, the bottom is for night rate electric and the top is the boost during daytime (99% sure of this but small chance it's the other way round). If you remove the metal covers you will see the thermostat control. This will set the max temp the water will reach, assuming the timer supplies power long enough. So you would adjust the bottom one to set the night heating. As mentioned be sure to isolate the power, and pull the fuse too (if one or the trip switch) to be sure as there is a high risk of touching the metal cover to a live connector as you remove it
2. The E7 timer sets when power is supplied to the element (via the main night rate timer and the boost control). The min is 4 hours. What I did was to have it come on the last four hours of the night so 4am to 8am in winter. Here is the details from the manual, you can get this from a search, but PM me if you want a copy. Again, this involves opening the timer up and exposing the live cables!