Help understanding electric boiler set up

lovely_trenty

My partner and I have recently moved into a new flat that only uses electricity to heat both hot water and heating.

We are on an economy 7 meter however I'm having trouble working out how to best use the system, as even though I've set the timer for the hot water to go on for 45minites from 6:30 am. It appears to be heating it constantly throughout the day. I also set the timer to off while we went away for a few days and we still had hot water when we came back so I believe it was still heating even without the timer, so I'm not sure what's happening. (But it is costing us a fair bit of coin)

There are 3 different switches, I'm not 100% but it appears there is one for a timer, one for a hot water cylinder, and one for a Heatrae Sadia boiler.

I'm new to how this all works, as I'm not from the UK and have only ever had a gas system before.

Can anyone help me understand the setup in the pictures attached below and what each part does? And how best I can use this system so that it is not running all day? I'm dreading to think what this is going to cost when we come off our current tariff and then into winter. 

Whole set up


Timer and 3 switches (L - Directly to the hot water tank. M - Directly to the top of the boiler. R - Into a bow which connects to the timer)


Hot water tank (The wire from the thermostat on the left goes into a box that also houses the wire from the boiler and timer. With the wire on the right going directly to the wall)


Heatrae Sadia boiler

Reed_Richards

Looking at the picture of your hot water tank, it looks as if you have two different ways of heating it.  On the right is an ordinary immersion heater, the one with "wire going directly to the wall".  On the left is a thermostat which is probably linked to the timer/controller and probably controls heating your hot water tank by passing hot water from your electric boiler through it.  Two of the pipes that go to/from the tank will get hot when this is happening.

Basically it's a crazy belt-and-braces set-up but you should be able to take control if you can work out which of the two means of heating runs on Economy 7 (could be both).   

jrawle

Assuming the picture was taken during the daytime, it seems all of the circuits are live at peak times, even the one connected to the immersion heater. I would therefore switch off the middle switch, the one that goes straight to the hot water tank. This is what is heating the water continuously all day. You don't ever need to switch this on unless the main electric boiler fails.

Other than that, you are doing the right thing. Set a time for the hot water to come on once a day during the Economy 7 hours. Do you know the hours of operation of your Economy 7? Make sure the hot water heating is off before the end (7:15 seems a little late). To be on the safe side, you could move it an hour earlier. The tank is insulated so will keep the water hot all day.

I assume the "electric boiler" is also connected to radiators? Once it is cold enough to require heating, this will be a very expensive way to heat the property. I suggest setting the timer only to put the heating on when you really need it. Depending on the E7 hours, if you want to take the chill off first thing in the morning, you could try this during the E7 period then turning off before peak rate starts. Also, if there is a room thermostat, set this as low as you can stand. If there are rooms you don't use much, turn the radiator off at the valve. All the usual tips, basically.