Fertraso Floor Fan 45cm 40W Chrome

A chromed floor fan with a 45 cm blade, three metal blades, three speeds and a tilting head, on a 40 W motor.

A larger blade on a smaller motor, and why that is right

This model has a 45 cm blade and a 40 W motor. The 40 cm version in the same range has a smaller blade and a 45 W motor. That looks the wrong way round, but it is exactly how fans work.

How much air a fan moves depends on the area its blades sweep and how fast they turn. That area grows with the square of the diameter: a 45 cm blade sweeps roughly a quarter more area than a 40 cm one. So you can move the same amount of air with a slower, lighter motor, as long as the blade is bigger.

In practice that cuts two ways. What you gain: at equal air movement this model turns more slowly, and turning slowly is calmer and cheaper to run. What you give up: a lighter motor has less in reserve when there is resistance, for instance when the fan is blowing close against a wall or into a crop.

Where it stands best

Give a blade this size clear space in front of it. A large fan standing right in front of an obstacle loses more than a small one, because the wider column of air breaks up sooner against whatever is there. Put it in a corner or along a wall with a clear run into the room, and tilt the head until the stream passes under or over your crop.

Technical Specifications:

• Format: floor fan, chromed
• Blade diameter: 45 cm
• Motor power: 40 W
• Speeds: 3
• Blades: 3 aerodynamic metal blades
• Speed control: variable
• Tilt: yes
• Frame: fully chromed metal
• Product type: floor fan

Frequently asked questions

Is 40 W not too little for 45 cm?
No. A larger blade sweeps more area, so it can move the same amount of air at a lower speed.

What do I give up against a heavier motor?
Reserve against resistance. Blowing freely into the room you will not notice; blowing into something you will.

How much space does it need?
Give it a clear run in front. A wide blade loses more against an obstacle than a narrow one.

Are the blades metal?
Yes, three aerodynamic metal blades in a chromed frame.