The Which? Best Buy award is given to
products with high total test scores that perform consistently well in
our rigorous lab tests and excel in all key areas.
We award the Energy Saver logo to
products that our testing shows are very energy efficient, meaning
they'll cost you less to run.
The Which? Don't Buy logo alerts you
to the products that performed extremely poorly in one or more key
areas of our tests.
Warming up time
The time it takes for the heater to heat up our 3.5x4m test room by 15 degrees. A 3-star heater takes twice as long as a 5-star heater.
Warming up energy use
How little electricity it takes for the heater to heat our 3.5x4m test room. The longer a heater runs the more electricity it uses. A 3-star heater uses 50% more electricity than a 5-star heater.
How well a heater maintains a stable room temperature via the thermostatic control.
Accuracy of power output claims
How well the heater matches the power output that is claimed for it by the manufacturer. A 4-star fan is within 10% of the claimed output. This matters if you are paying more for a more powerful heater, or have a large room to heat.
Ease of use
A three person panel examined how easy the heater was to initially set up, how easy it is to turn on, off and set different modes, clarity of instructions and more.
More stars means the heater is quieter and has no annoying tones in operation.
We check prices every month and for Best Buys we give the cheapest widely available high street price we can find. Prices for other models are a guide to what you should expect to pay.