Electric heaters

• Fan: A fan is an effective way to break up the layers of cold and warm air in a room. While noisy, you don't have to use them continuously. Just switch them on for a few minutes, to warm up the room.
• Cord storage: This allows you to stow the cord neatly when the heater is not in use.
• Controls: The controls should be clearly visible, easy to access and easy to use. Markings should be easy to read with good contrast. The more heat settings the better – you'll have more flexibility to control the room temperature.
• Timer: With a timer, you can warm up a living area before you get up in the morning or arrive home from work. You can also have a bedroom heater turn itself off after you've gone to sleep.
• Mobility: Oil-filled heaters are heavy and can be difficult to move around because of their size and shape. Try moving the heater around in the shop. There is usually a recessed handle at the control panel end: it should give a good grip. Some models have 4 castors, others a combination of castors and wheels. Some have a single pair of large wheels at one end, so you have to lift the handle end to move the heater. Weight then becomes important.
• Clothes drying: Clothes must not be draped over a heater. Some heaters come with a detachable drying rack that spaces the clothes away from the heater. For others, you can buy a separate drying rack.
• Thermostat: This maintains a desired average room temperature (as long as it's within the heater's capacity), and should have a control that's easy to read and set.
• Cleaning: Heaters that are largely comprised of flat, uninterrupted surfaces are easiest to clean (panel and convector models topped the cleaning test). Oil-column heaters with nooks and crannies are the most difficult.

Our test results show that the upwards convection currents of many fan-less heaters create a pool of hot air near the ceiling.

But there’s an answer: we took one of the oil-column heaters and did some extra tests using a small desk fan placed on the floor and aimed at the heater.

The results were dramatic – the heater raised the average room temperature by 5°C three times faster when we tested it with the fan.

These heat distribution charts represent a vertical cross section of our thermal lab with the heat source at the bottom left. The green shades are comfortable temperatures, red is too warm.

The oscillating fan heater distributed heat fairly evenly, but the oil-column heater couldn’t break up the layered air temperatures. This shows using a fan-less heater can result in cold feet and a hot head.

Our table allows you to estimate the capacity of heater you’ll need to maintain a comfortable temperature.

The table assumes a standard ceiling height of 2.4m. If you have high ceilings, adjust the estimates up.

Tilt switch

Tilt switches turn the heater off if it falls over to reduce the risk of fire. They’re not mandatory, but we think they’re essential for any portable heater with a radiant element.

Thermal cutout

All models should have a built-in thermal cutout, to turn the heater off if it overheats.

Oil-filled heaters

The relatively low surface temperature makes oil-filled heaters safer than most other heater types. But some models have narrow exposed fins that get quite hot.

Models with wide flat fins or a casing over the fins, and a protective heat shield at each end are safer.

Because they are tall and narrow, column heaters are inherently less stable than other types. They are also heavy.

If a model with narrow exposed fins topples onto a small child, it can do quite a lot of harm. Having wide or enclosed fins helps. A tapered shape may help stability. If there are toddlers about, a loop of chain around the top fin tube and attached to a wall could stop a nasty accident if the child tried to pull the heater over.