If you have electric heating it will normally be a system using electric storage heaters, commonly known as ‘Economy 7’.

Economy 7 is the tariff by which electricity is supplied. You’re charged different rates for the electricity you use depending on the time of day or night it is used. The majority of energy supplied for heating and hot water will be at the lower (night) rate, when the cost of electricity is cheaper. The remaining electricity needed for non-heating purposes (cooking, ironing, watching television, etc.) is charged at the higher (day) rate. This costs nearly three times as much as the lower rate.

Hot water is supplied from a high capacity storage cylinder. The cylinder, which has a tank above, is insulated and fitted with two immersion heaters.

There are two basic ways of using the hot water system, the best choice for you will depend upon your lifestyle and water usage.

Which settings should I use to get the most efficiency?

If you use a lot of hot water for cooking and washing, then using the night storage heater is usually the cheapest method. Using the immersion heater at the bottom of the cylinder, a full tank of water is heated at the cheap night rate. You can then use the stored up heated water as and when you need during the day. The top immersion heater can then boost the water temperature if needed during the afternoon or evening.

If you don’t use huge amounts of hot water it may be cheaper to use the top immersion heater only as required to get hot water as you need it. You could get most of your hot water on the cheap night rate - especially if you stay up late or get up early. The amount of money you save will depend on you timing your water use to avoid the more expensive day rate.

Night storage heaters

Storage heaters charge up using the cheaper rate electricity. Heating elements warm up an insulated mass for up to seven hours each night. The stored heat is then discharged over the following day, the discharge is partly controlled by a thermostat operated damper. The amount of heat the unit takes in is determined by a remote sensor which monitors the room temperature.

Operating the night storage heater

  • Make sure that the fused spur on the wall by the heater is switched on
  • Set the input control to the required setting, typically between 3 and 5 (this may need some experimentation)
  • Check that the boost control is set to number 1

Using the boost control

The boost control is numbered 1-5. The heater will work well most of the time at setting 1. You can increase the heater output if you need extra heat during the afternoon and evening, by turning the boost to numbers 2-5. Remember to reset back to 1 before you go to bed.