Electric storage heaters

Electric storage heaters use electricity to generate heat. They store this heat inside their core, which is often made from heavy clay blocks. 

Older storage heaters use input and output dials to control heat. The input controls the electricity – the higher you set it, the more electricity it will use and the more the heater will heat up at night.

The output dial controls the release of heat – the higher you set it, the quicker heat emits from the heater. If you set the output too high, the heater may run out of heat before the end of the day. 

For more information, read our guide on electric storage heater controls.

Some storage heaters also have convector heaters. These usually appear as a grill at the top of the unit. These give you a ‘boost’ to your heating, in case you run out of heat. Try not to rely on these too often, as for most people it’s cheaper to use the energy they’ve bought at cheaper rates overnight.

Electric storage heaters work with special electricity tariffs that provide cheaper rates at certain times of the day. The most common of these is known as Economy 7.

These ‘economy’ tariffs relate to a type of meter with two distinct electricity rates (or dual rate tariff). This means you get a cheaper rate during a certain period, usually overnight, when you can charge your heaters. You can also power an electric immersion heater in your hot water cylinder, if you have one. 

Electric storage heaters originally used two meters, separating the electricity you use for heating and hot water from the electricity you use for lighting, cooking and electronics. These two meters were then combined into a single meter with two separate readings. Now you can simply use a smart meter, which lets you access dual rate or smart tariffs with a single meter and fuse box. 

Economy 7 isn’t the only meter arrangement available, though. So, if you’re unsure, speak with your energy supplier to understand what meter you have and how they bill you for the electricity you use. 

If you live in Scotland and have more than two electricity readings, or don’t understand your metering or billing, it’s possible you have restricted meters.

Restricted meters have complex tariffs, often providing afternoon or early evening ‘top up’ cheaper rate periods in addition to an overnight period.

You can speak to Home Energy Scotland for free and impartial advice about this. 

Storage heating technology has improved considerably since storage heaters first came about in the 1960s. Storage heaters made after 2018 must meet stricter efficiency standards and come with better controls – although it’s still possible to buy older models. 

Upgrading to modern storage heaters could make your home more comfortable and save you money on your heating bills. Compared to older storage heaters, modern heaters: 

• Have higher heat retention. This means they hold heat for longer. Better home insulation slows the rate of heat loss from the hot core, meaning there’s more heat available to you when you need it.
• Can release heat more quickly when needed, sometimes using a fan to send out warm air.
• Generally come with improved heating controls, including an automatic charge control, thermostat and programmer. 

The programmer lets you set the temperature you want the room heat up to and when. 

The automatic charge control works out how much electricity it needs to store to meet that programme. It only uses the amount of electrical charge it needs to meet the programme. 

The thermostat tells the heater to release more of heat if it detects the room is colder than you want it. It also stops releasing heat if it detects the room is warmer than you want it. 

These controls work together to ensure that once you set the programme, the heater can control itself without you needing to make any adjustments. Ask your installer to explain the controls to you.

Some modern electric storage heaters are in a special category known as high heat retention storage heaters. You may see these as recommendations in your home’s Energy Performance Certificate. These heaters:

• retain more heat than other storage heaters
• are well insulated
• have automated controls

You can find a list of high heat retention storage heaters on BRE’s Product Characteristics Database. 

No, a registered electrician should replace your storage heaters. Storage heaters are very heavy because of their heat-retaining core – some larger models weigh more than 150kg. Storage heaters also need a connection to the correct circuit in your home and are hard-wired to the circuit. Only a registered electrician should do this.

Also, storage heaters installed before 1974 may contain asbestos, in which case you should contact a specialist asbestos contractor who can handle and dispose of them safely. 

A trained installer will also be able to advise you on which size of heater you need. This is important because over-sized heaters cost more to buy, and might end up using more electricity than necessary. Meanwhile, a heater that’s too small may not deliver enough heat for your home. 

The installer might ask you to turn off the heaters you’re removing for 24 hours or more before the appointment, to let the core cool down enough for them to handle it. 

Here’s how you use electric storage heaters: 

1. Set your temperature 
2. Set your timer 
3. Consider your setback temperature 

Once they’re set, digital electric storage heater controls are easier to run than manual controls. This is because they’ll automatically store enough heat for your set routine. 

Set your temperature 

Select a temperature that’s comfortable, usually somewhere between 18°C and 21°C. Remember, setting a lower temperature means your storage heater doesn’t need to store so much heat, saving you money.

But, if you set it too low, the heater won’t store enough heat for the next day. Because storage heaters don’t recharge until the following day, you can’t quickly boost the temperature later – so make sure your setting matches your needs. 

Set your timer 

Most modern storage heaters have timer modes like ‘out all day’ or ‘home all day’ for convenience. Select one of these modes and the heater will release heat at set periods throughout the day in line with your routine. 

If you prefer, you can specify set the time and day for your storage heater to turn on and off. 

Consider your setback temperature 

Some storage heaters have a ‘setback’ temperature. This is the temperature the heater will try to keep the room at while it’s set to ‘heating off’. 

This can be useful to stop the room getting too cold. It may also mean the heater doesn’t need to work as hard to bring the room up to a comfortable temperature later on. 

However, if you set your setback temperature too high, your electric storage heater will use up its stored heat faster. 

To use an old storage heater, you should: 

1. Set your input dial ahead of time
2. Adjust your output dial to suit your daily routine
3. Turn your output to ‘low’ at night 
4. Only use the boost function if you really need it 

Set your input dial ahead of time 

The higher you set your input, the more electricity the storage heater will use and the more the heat it will store. How high you set the input dial depends on how cold you think it’s going to be the next day. 

If you think it will be cold, set your input high so the heater stores enough heat to last you the next day. If the weather will be milder, turn it down so you don’t store more heat than you need. 

Remember, the higher the setting, the more electricity you’ll use and it will cost more to run. Also remember that any changes you make to your input setting won’t happen until the next charging period. 

Adjust your output dial to suit your daily routine 

The higher you set your output dial, the quicker the heater will release its stored heat. If you set this to minimum, the heater will still release the heat that’s been stored – it just does it more slowly. 

Think about your daily routine and see if you can set your output control to suit this. To make the heat last all day, we recommend you leave the output dial on the minimum setting if you’re out during the day. 

If it gets colder during the evening, turn the dial up higher to let the remaining heat escape faster. 

Adjusting the output dial won’t cost you any money. This is because it’s only releasing the heat you’ve already paid for – it’s just released quicker. 

Turn your output to ‘low’ at night 

Make sure you set your output dial to minimum when you go to bed. This will stop heat being given out while you’re asleep, and the storage heater can focus on storing heat for the following day. 

Only use the boost function if you really need it 

You should only use your ‘boost’ if you’ve run out of stored heat. It may use the most expensive electricity rate if you’re on an Economy 7 tariff. Try to use this only in the coldest weather and when you’ve run out of stored heat.

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