Suction power

As users of vacuum cleaners, our experience of suction power is primarily determined by the vac’s cleaning performance, i.e. its ability to efficiently suck up the dust and dirt in our homes. How strong is it? How effective in a single sweep? Does it manage or skip the heavier objects?

The power of a vacuum cleaner is measured in watts. Sometimes the suction power is measured in ‘airwatts’ – which is, however, a somewhat constructed term whose job it is to mark the difference between motor power and suction power. This is why there is always two figures for watts in the vacuum cleaner specifications (ex. 400/280) – even when the term airwatts is not directly mentioned.

Naturally, the suction power is generated by the vac’s motor, and if one compares models by comparing watts to watts, generally it can be said that the larger the motor (the higher the wattage), the better the suction power. Most often this is true, but it is not the whole truth. It is the efficiency that counts, i.e. how the motor power is utilised in the transfer between motor and nozzle.

The effect must necessarily be measured at the end of the cleaning hose, where an amount of the power – due to the principle of the vaccum motor – has been converted into an airflow. It is this airflow that carries the dust from the nozzle to the dust bag. Hence the term airwatts: watts is the input power, airwatts the output power – i.e. the suction efficiency.

You can actively help your vacuum cleaner keep up the good work by keeping the filter clean and changing the dust bag regularly, and do not forget to always use the proper dust bags prescribed by Nilfisk. A clogged filter and a crammed dust bag are certain to impair the suction power no matter how high the vacuum cleaner’s wattage.