As energy prices continue to squeeze household budgets across the UK, finding efficient ways to stay warm is a priority for many. In the winter of 2025, I put two different radiator fans to the test in my own home to see if they could help heat a large living space more quickly and affordably.
Putting Radiator Fans to the Test
My living and dining area is the largest room in the house, and consequently, it has always been the slowest to warm up. Despite investing in upgraded radiators, achieving a comfortable temperature took longer than in other rooms. To tackle this, I trialled products from two brands: the SmartAir Boost XL Fan Heater (£70 at Argos) and the SpeedComfort radiator fans (from £49.95 on Amazon).
Design and Setup: A Clear Difference
The two products operate on a similar principle—using fans to circulate warm air from the radiator—but their execution differs. The SmartAir unit sits on top of the radiator, blowing heated air horizontally out into the room. In contrast, the SpeedComfort fans are designed to fit underneath, directing airflow upwards.
This leads to an immediate aesthetic consideration: the SpeedComfort fans are discreet and largely out of sight, while the SmartAir is visibly perched on the radiator. Both were very simple to set up and became operational within minutes. A key feature they share is a thermal sensor that automatically switches the fan on when the radiator heats up and off when it cools down.
A notable advantage for the SmartAir is its battery function, allowing for cord-free operation, albeit with a battery life that isn't exceptional. The SpeedComfort models require a permanent plug-in connection.
Performance and Practical Drawbacks
In terms of raw performance, both devices made a tangible difference in how rapidly the room warmed up. However, I found the SmartAir's method of pushing warm air directly into the living space more effective than the SpeedComfort's upward draft.
Nevertheless, each product has significant drawbacks. For the SmartAir, the primary issue is noise. The highest setting is particularly loud, though the low setting is effective and more tolerable. This could be problematic in a quiet bedroom but is less noticeable in a busy living room with the television on.
The major hurdle for the SpeedComfort system is cost. While they work well, the price point makes them a less viable solution for many. To equip every radiator in a typical house could easily exceed £900, a substantial upfront investment that would take years to recoup through energy bill savings.
The Verdict: Which Radiator Fan is Best?
After extensive testing, the SmartAir Boost XL emerges as the preferred choice. Its direct airflow into the room provides a more noticeable heating boost, and its lower initial cost offers a more accessible route to potential energy savings. The noise is a compromise, but one that is outweighed by its performance in a main living area.
For those seeking a cheaper alternative, radiator reflector foil, available from retailers like Screwfix for under £6, remains a popular option to prevent heat loss through walls.
The SmartAir Boost XL Fan Heater is sold by Argos, Yimbly, and HighStreetTV for around £70. SpeedComfort fans are available on Amazon and at Currys, with prices starting just under £50.
