Successful textile washing depends on the right combination of four elements – mechanical and chemical action, time and temperature – a formula described as Sinner’s circle.

The wash program, which will have been selected to suit the type of load, will determine the time and temperature.

The chemical factor involves the action of the detergents, water and bleach that are used to clean and whiten the work. The mechanical action may be even more significant. The washing machine’s action is heavily affected by the loading ratio – typically 1:10 for a normal load and 1:20 for delicates – and also by the water level.

During the washing process, the goods absorb water, the exact amount absorbed depends on the textile. The extraction phase of the washing cycle is designed to remove the maximum amount of water before the load is dried. The greater the amount of water extracted, the quicker it will dry.

Speed and performance

The washer’s extraction performance is defined by the G-Force of its centrifugal acceleration. This depends on the on the rotational speed (rpm) and diameter of the drum. Washers with different diameters will therefore have different G-forces and, as a result, the moisture that remains in the linen or garments after extraction will vary according to the machine.

Electrolux’s lab tests show that the amount of water extracted reduces considerably when the G-force falls below 300G.

To create a faster, more effective spin, washer-extractors are constructed with a suspended system, with space between the drum and the base of the machine.

This allows the drum to spin freely and is key to achieving the desired G-force but if the machine becomes unbalanced during the spin cycle, the amount of moisture that is extracted will fall significantly. This will not only affect the amount of energy needed to dry the linen/garments but also the life of the equipment.


A case-study from a Spanish prison laundry highlights the importance of balance.

Electrolux Professional had recently supplied a WSB4500H barrier washer (G-Force 350), a T41200 dryer and an IC4 4832 LF ironer. The prison already had 50kg washers from another supplier.

Soon after Electrolu Professionalsupplied the equipment, the customer called to complain that the equipment was not delivering the promised productivity and said he thought that the problem lay with the ironer.

Technical managers found that the ironer was working properly so the degree of residua moisture in the linen post-extraction was checked. The results surprised all concerned. Tests on the Electrolux machines showed that there was 53% residual moisture in the linen and garments that had been washed.

The result from the other machines was higher at 65%. Similar problems were also found in four (non Electrolux) machines in two other prisons.

All machines were operating a six-minute extraction cycle. This was found to be working correctly but the machines were going out of balance during extraction.

The machines’ G-force, as measured by a tachometer, was as stated but out-of balance loads had reduced the G-force so the machines were extracting less water.

All washers run the risk of imbalance during extraction. The risk is greater if machines are overloaded or underloaded.

Imbalance occurs when the load is unevenly spread in the drum so the weight shifts more to one side than the other and this causes the drum to vibrate. This acts like a brake, making it more difficult for the motor to turn the drum. Unless the machine has been designed to compensate, an imbalance can eventually stop the extraction leaving more water in the work.

Out of balance loads can also increase the stress placed on the machine and if imbalance occurs frequently it can lead to increased maintenance and may eventually shorten the machine’s life.

Electrolux Professional washing machines have been through a rigorous research and development process to ensure that they can withstand a significant shift in the balance of a load. The suspension system has a combination of springs and shock absorbers that is designed to reach maximum efficiency. The machines’ frequency controller and flexible programming ensure the best performance and minimises water retention.

The company measures the extent of imbalance by the hectogram ( a unit of mass equivalent to 100grams).

Its machines can handle as much as 23 –32 hectograms of imbalance, while still minimising water retention.

Some washers may not compensate to the same degree. If, just as an example, a machine can only cope with a maximum of 13 hectograms of imbalance, this could reduce the drum speed at that level to 110G and the residual moisture could be as high as 71%.

In a 6kg load, this will leave 1,060 grams of additional moisture, which will prolong drying time by 10 minutes 24 seconds and use and extra 1kWh of energy. Over 10 years and based on 8 starts per day, this could add up to 30,000 kWh of extra energy. Assuming a price of €0.2/kWh, that would add up to around around €6,000 over 10 years, or €600 a year. So using a machine that has a greater imbalance compensation could produce considerable savings.

It is clear that a washing machine that can cope with wash load imbalances will not only save energy and maintenance costs but will also prolong the life cycle of the equipment itself.

As Juan Prado Lopez, Electrolux’s Global Segment Manager, Commercial Laundries, says: “Balance is important. Electrolux’s suspended extraction system is of the highest quality, having been tested both in the lab and over time. We invest 3% of our budget on research and development to ensure that our machines achieve the best performance.”