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Hitachi

Heat Recycling Dry Big-Drum for Washer-Dryer

[Image] Ready-to-wear cloths are proof of machine's energy conservation and water saving credentials!

Heat Recycling Dry Big-Drum for Washer-Dryer BD-V3100/V2100 makes full use of Hitachi's technology.
The Big-Drum washer-dryer includes a range of mechanisms that deliver excellent energy-conservation and water-saving performance.

  • * The products described on this page are only available in Japan.

(Released in March 2009)

What is the Heat Recycling Dry Big-Drum for Washer-Dryer?

Because top-loading washing machines wash clothes in a pool of water, they are limited in their capacity to save on water use. In the case of standalone driers, not only do they require the user to transfer clothing from the washing machine by hand, they also run up electricity bills because they dry clothing using hot air produced by a heater. Also, the limited drying space inside the machine can cause wrinkles and twisting.
The new Heat Recycling Dry Big-Drum for Washer-Dryer BD-V3100/V2100 solves these problems and yet is also an eco-friendly product.

The biggest difference from other products is the significant saving in power consumption achieved by using recycled heat for drying. The new machines are the first in the world to adopt this technique(*1).
First, the recirculating auto shower function allows the detergent to penetrate right through the clothing, then the recirculation and agitation function lifts the clothing up to the top of the large-capacity drum and drops it down again. The 61 cm diameter drum on the machines is the largest in the industry(*2). These functions shorten the running time and make effective use of water, giving the machines the best available water saving capability (*3).
The built-in KAZE IRON (blower iron) function smoothes wrinkles by blowing air through the clothing at a speed of 360 km per hour using a jet fan motor. This eliminates the time-consuming task of ironing the clothing afterwards.

[Image] The industry's largest drum diameter(*2)

*1
The machines were released on October 12, 2008 and are the first household washer-dryers to use this technique. The drying technique recovers waste heat from the gated intake and uses a fan for compression heating.
*2
As of October 12, 2008. Among household washer-dryers.
*3
BD-V2100. As of October 12, 2008. Among household washer-dryers (9-kg washing and 6-kg drying class). Normal water consumption for washing a 9 kg laundry load is 74 L. Normal water consumption for washing and drying a 6 kg laundry load is about 58 L.
*
The actual performance figures and explanations in the text are based on actual performance in Japan.

Using recycled heat for drying avoids heat wastage and delivers a significant reduction in power consumption!

The secret of the Big-Drum washer-dryer's energy conservation is that it the first in the world to use recycled heat for drying(*1). This new system significantly reduces power consumption by reusing, rather than wasting, the heat generated during operation.
As shown in the figure below, the heat energy generated from the motor and heater is recovered by the newly developed Eco Flap (gated intake) and used to provide hot air for drying. The heat generated by running the jet fan motor at 14,000 revolutions per minute and the air compression heat are also recycled to provide hot air for drying. Heat from the motor used to drive the drum is also transferred to the inside of the tub by conduction and increases the temperature of the tub.

[Image] World's first(*1) dryer to use recycled heat

The combination of these three systems has reduced power consumption by about 80% by reusing previously wasted heat generated during operation

[Image] Comparison of power consumption during operation

[Image] - Compared with conventional models - Approx. 80% power saving

*4
When temperature of leftover bath water is 30°C.

Why the Big-Drum Washer-Dryer is Number One(*3) for Water Conservation

The number-one performance for water conservation (*3) is achieved by the recirculating auto shower function that recycles the water and repeatedly sprays it over the clothes to do an effective wash with a limited amount of water. The width of the shower is repeatedly widened and narrowed so that the detergent solution penetrates evenly throughout all the clothing. In addition to its eco-friendliness, the agitation washing effect resulting from the Big-Drum washer-dryer's superior height of fall gives the machine superior washing performance compared with conventional models.

[Image] - Compared with conventional models - Approx. 81% power saving For a 6 kg wash and dry load

[Image] Recirculation delivers maximum water conservation

Another industry first (*5) is the "Ag sterilizing bath water pump unit". A sterilizing unit containing silver beads incorporated into the end of the bath water pump hose eliminates 99% of germs in leftover bath water (*6). The unit allows washing and rinsing with clean water. It is recommended for people who wish to save water but are concerned about the cleanliness of leftover bath water.
A world-first (*7) system for reusing bath water that uses a pump to extract used bath water for both washing and drying effectively reduces the volume of tap water used in drying to zero (*8). This achieves significant water savings.

Hitachi's technology is designed from a user's perspective and delivers maximum water savings. This is how we got to be number one in water conservation (*3).

[Image] Big-Drum Washer-Dryer is Number One for Water Conservation(*3)

*5
Released on June 10, 2008 in Japan. Among household washer-dryers.
*6
Tester: KITASATO Research Center of Environmental Sciences. / Test method: Agar plate culture method. / Sterilization method: Silver ions. / Reduction in germs: 99%.
*7
Released on July 10, 2006. Among household washer-dryers.
*8
Tap water usage for drying when the bath water pump is used for a complete wash and dry cycle. For a drying-only cycle, 4 L of tap water is used to prime the bath water pump.
*
Japan has an eco-friendly practice of using leftover bath water for washing clothes.
*
The actual performance figures and explanations in the text are based on performance in Japan.

The Hitachi Group views the Heat Recycling Dry Big-Drum for Washer-Dryer as one of the ways of achieving our Environmental Vision 2025, with its goal of helping to reduce CO2 emissions by 100 million tons annually by 2025.

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