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Room heaters

Room heaters are used to heat a small space and are normally portable or fitted to a wall. Most room heaters use gas or electricity.

Room heaters are convenient appliances that provide focused and localised heat which is particularly suitable in a room for people that are elderly, ill or with limited mobility. But they can be expensive.

[NB if you're looking for our information on night storage heaters, click here.]

They consume a lot of gas or electricity if used to heat up a space quickly, and are likely to cost a lot more than a central heating system.

Ideally, room heaters should only be used as a secondary or supplementary source of heat. Even then, you should use the right heater for the space you want to heat, and carefully control the temperature and the time you have the heater on. Heaters that have these controls are often cheaper to run.

What kind of room heater?

When you’re deciding on what room heater to use, consider first what purpose you want it to serve.

1) Heating a whole room for a few hours or more
For this, you should use a convector heater. These work by warming the air immediately next to them which then naturally circulates relatively evenly around the room. Convector heaters are a good choice if you need a supplementary heating source to warm up a room for a few hours at a time. They take a little longer to work, but this type of heater can be easily controlled with a timer and thermostat, so you don’t overheat the room and you save money. You can get both electric and gas convector heaters, and oil filled radiators are also a type of convector heater.

2) Heating a room for a short period of time 
For a quick blast of warmth, or for more directional heating, you should use radiant or fan heaters. These work quickly and are useful if you want to warm up only part of a room for a short period. Unlike convector heaters, they don’t achieve an even level of heat throughout the room, so don’t bring the same level of comfort. They rarely have  thermostats or timers which is likely to make them a more expensive option over time. Halogen heaters, electric bar fires, open gas fires and bottled gas fires are forms of radiant heater. Technically speaking, they don’t heat the air (like convector heaters) but transfer heat through electromagnetic waves in the same way that an log fire warms a room and the sun warms the earth.

Electric room heaters

These include ‘radiant’ bar fires (below, picture 1), warm air heaters (2), oil-filled radiators (3), fan heaters (4), and halogen heaters (5). They are all expensive to run and not appropriate as a main heat source.

Electric heaters are all considered to be 100% efficient (i.e. they turn all the electricity they use into heat), but some are more expensive to run than others because they provide more heat. The cheapest are halogen heaters and oil-filled radiators; the most expensive are bar fires and fan heaters.

If you have to use an electric room heater, use it only when necessary and consider the following:

  • Use a timer if it has one, if not, you can buy a timeswitch for the plug from a hardware shop.
  • If the heater has a thermostat make sure it’s not turned up too high.
  • If you are on Economy 7, avoid using it for long periods within the peak hours if you can. It's better to use night storage heaters that are charged at night.

The table below shows typical running costs for a range of electric room heaters. The actual costs will vary as electricity prices change, but what's important is how they compare with each other.

 Typical heat outputRunning cost per hour
(standard meter)
Running cost per hour
(Economy 7, night)
Running cost per hour
(Economy 7, day)
Radiant bar fire2 kW28p13p36p
Halogen heater1.2 kW17p8p22p
Convector heater2 kW28p13p36p
Fan heater2 kW28p13p36p
Oil-filled radiator1.5 kW21p10p27p

Heat parade (electric) 1) radiant bar fire, 2) convector heater, 3) oil-filled radiator, 4) fan heater, 5) halogen heater.

Gas room heaters

These include traditional gas fires (6), convector heaters (7), open gas fires (8) and bottled-gas heaters (9). All can be run on mains gas or liquid petroleum gas (LPG). Bottled gas heaters, gas convector heaters and paraffin stoves don’t need flues (chimneys). However, the water vapour they produce can cause condensation which will lead to damp and mould problems if the room is poorly ventilated.  

The table below shows typical running costs for a range of gas room heaters. Again, the actual costs will vary as gas prices change, but what's important is how they compare with each other.

 Heat outputEfficiency ratingCost per hr (mains gas)Cost per hr (LPG*)Cost per unit heat (mains gas)Cost per unit heat (LPG*)
Radiant gas fire (on full)5KW63-81%25-32p41-54p5-6p8-10p
Radiant gas fire (on low)1KW40-65%6-10p10-17p6-10p10-17p
Gas convector heater (on full)3KW60-85%14-20p23-33p5-7p8-12p
Open decorative gas fire2.5KW20-50%20-50p33-84p8-20p13-33p
Closed gas fire4KW60-80%20-27%33-45p5-6p8-10p
Bottled gas fire4KW100%*n/a66pn/a17p

* assuming LPG propane supply except for bottled gas where assumed to be using 15Kg Butane cylinder

If you are on mains gas, then gas central heating is the best way to heat your home. If you have to use electricity then the best way is with night storage heaters on an Economy 7 tariff.

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