Portable heater reviews: Features explained

Which? has reviewed and rated popular electric fan heaters - find out which scored the best in our full portable heater reviews, including models from Dyson, DeLonghi, Dimplex and more. If you are having problems with your central heating, you can also find tips on maintaining your boiler in our heating section. 

Read on for advice on how to choose the best fan heater for your needs.

What types of fan heater are there?

Portable fan heater

These are the lightest and most portable type of heater. They’re great if you want to heat a room fast as they warm up quickly.

An oil filled portable heater

Oil filled heaters are cheap to run

They’re also easy to set up first time round - usually you just take the fan heater out the box, plug it in and you’re ready to go. On the downside, this type of portable heater can be quite noisy.

Oil-filled portable heater

Some oil-filled heaters can be really slow to heat up after switching them on. Although you can find mini oil-filled heaters, most are fairly heavy and cumbersome. 

Look out for models that come with castors, which will make the heater easier to move around. Often you have to fit these, or small stabilising feet that they come with, yourself. 

Oil-filled heaters are usually the cheapest to run. When we tested them in 2007 we found that they don't always achieve the power claimed by manufacturers, so you might not get the heating power you expect. 

Convector portable heater

Convector heaters are quite tall, like oil-filled heaters, but are thinner and usually much lighter - making them easier to move from room to room. Like fan heaters, they heat up quickly, but are also quieter. Unlike the other types, all of the convector portable heaters we tested are wall-mountable, which means they can be located out of the way. We have not tested them recently.

A convector heater

Convector heaters have many advantages

Brackets and instructions for wall mounting are included, but you do need to drill holes in your walls. Like oil-filled models, they also usually need a bit of setting up.

How powerful does a fan heater need to be?

Another important consideration is the power of the heater – measured in watts (W) or kilowatts (kW). 1,000W is equal to 1kW.

Higher power means the heater will be better for heating big rooms. If it’s a small room you want to heat, a good, low power portable heater (less than 2,000W, say) will be fine – and it will be cheaper to run. However, manufacturers’ claimed power is not always what it seems.

We've tested each heater reviewed at the Which? test lab to see whether it achieved the full claimed power. We found that some heaters don't - you can read our product-by-product portable heater reviews to find out which models were, and which weren't, as powerful as they claimed to be.

In the case of oil-filled heaters, once the oil inside reaches a certain temperature, the heater switches itself off for a while until the oil cools. Then it switches itself on again. The heater appears to be on throughout this process and is still hot, but this on/off nature of some heaters means that maximum claimed power, and therefore heating potential, isn’t achieved.

What useful fan heater features should I look for?

Fan heater timer switch

A timer, available on some models, is useful for setting a heater to turn on just before you get home or wake up. So, no waiting around for the heater to warm up.

A cold air setting on a portable heater

Portable heaters can help to cool you down

Cold air setting

Some heaters can help cool you down too. They're not nearly as effective as a dedicated air conditioner, but a light breeze of cold air is better than nothing. This feature is most often found on fan heaters.

Fan heater climate control

Climate control is a useful feature to have. Your portable heater will heat the room, and when the desired temperature is reached (you may need to turn a dial at this point to tell the heater the room is warm enough), the heater will try to maintain the room at that temperature. 

If a door or window is opened for a length of time allowing cold air in the room, the heater will work to keep the temperature stable. Some heaters, meanwhile, have a more advanced system where you actually set a specific temperature using an LCD display and the heater tries to maintain that temperature.

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