Swapping lower emersion heater supply with top.

Viper_7

We are on Economy 7 and all our water/heating is electric.

Our hot water cylinder is a twin element 160litre jobbie.
The lower for heating a full tank is on the Economy 7 supply. Coming on for 7 hours a night, and a two hour top-up in the afternoon.
The top one is the standard supply on normal tariff which people would use say as a quick top-up.

Now we are only two adults and a little un and I feel we never ever would use a full tank full of hot water. So I believe we have "surplus" hot water.
Now the cylinder is double foam insulated and is very efficient but it's still bound to lose heat.
What I'm thinking is switching the supplies around. So the upper element is on the Economy 7 supply and heats up over night. This will of course be on less as there's less water to heat until the thermostat trips. It is adjustable from 30 - 80 degrees C so if I do find we are using it all, I can just up the temperature a little.

We only use hot water for bathing/washing dishes (no dishwasher)
Washing machine is cold water fed.

What do you think? surely a saving to be made here with only heating the water we really use.
I'd say the top element would heat around 50 litres. The lower around 140L - based on the positioning and capacity of the cylinder.

Any issues anyone can think of, of swapping the supplies over?

Vipes

tomstickland

I considered doing this too.
(I have the same set up as you).
I think it would work.
In my case I measured the heat loss and it's around 3 units per day. ie: about 12p a day.

Viper_7

Well, have swapped them over and 3/4 of the way through the day and still have hot water, so looks like it was worth while.