Immersion switches

Effalumps6

Ivw I’ve 2 switches and confused which one to leave on !!!
there’s only me so wonder if leaving both off then switch on and hen needed or washing up .  I’ve an electric shower no bath !!!! 

comeandgo

If only you and electric shower I’d not put them on at all.  Fill kettle when needed.

Gerry1

The lower heater should be left on.  The upper heater should be left off.  This assumes you have Economy 7 or a similar two-rate tariff.

In emergency you can switch on the upper heater to get half a tank of hot water, but it will be at cripplingly high rates in the daytime. Ideally it should have a one-hour or two-hour timer so that it can't be left on accidentally.

However, an electric shower is very bad news unless you can always use it only at the night rate.  Far better to have a power shower that uses stored hot water.

Do the sums to see whether single rate would be cheaper.

Do you have electric heating and if so what type, e.g. night storage heaters, panel heaters, convectors?

lohr500

@comeandgo advice is probably your best option if you only need small amounts of water for washing up. Switch off both immersion heaters and just use a kettle as needed.


Do you have an Economy 7 electricity supply (or possibly Economy 10, or some other dual rate tariff?

Usually with such a supply, the bottom immersion heater in the tank would be wired to the Economy 7 circuit and the upper immersion heater wired to the normal circuit. 

The theory being that the whole tank is heated on off peak electricity using the bottom immersion heater. Then if you need more hot water during the day, you use the upper immersion heater to "boost" the hot water in the upper part of the tank only.

With such a setup, if you need plenty of hot water, you would leave the bottom immersion switched on and only ever switch on the upper immersion heater as a last resort if you run out of hot water.

How is the house heated? Storage heaters,gas,oil,lpg, plug in heaters? Depending on your current tariff and heating method, you may want to review if a single tariff or Economy 7 tariff is best for you.