Portable heaters: How we test
Test chambers
For our heating tests, we built two special test chambers. One of them simulates a living room, measuring 3.5mx3.5mx2.5m, and is extremely well insulated to stop heat loss through walls.
The second is a smaller refrigerated chamber capable of being chilled to sub zero temperatures. Vents between the two allow cold air to flow for our tests. Tiny thermometers were set up, and linked to monitoring equipment outside.
Heating and cooling
We test all the heating functions
Our first test measures how long the heater takes to warm up. Each heater starts at room temperature. We switch it on and measure how long it takes for the room to reach a steady temperature.
We then measure how hot surfaces in the room, such as walls, floors and ceilings, get after the heater heats the room to a steady temperature.
We also measure how well the heater can keep the room temperature stable by allowing cold air into the room – the best heaters at this point work harder to compensate.
We measure how heaters perform in different conditions
For cooling performance, we measure the strength of the cold air flow at different distances from the heater - on heaters with a cold air setting.
Ease of use
Three assessors examine how easy it is to set the heater up for the first time, how clear the instructions are, how easy different settings are to select, the ease of turning on and off, and more.