Page 86 - WaterSense at Work

October 2012
Ensure multi-load washers are preset to meet a water factor of 8.0 gallons per
cycle per cubic foot of capacity or less.
Work with the equipment supplier to provide an ongoing service and mainte-
nance program.
Consult the laundry chemical supplier for laundry methods that require fewer
wash and rinse steps.
Use detergents formulated for high-efficiency clothes washers. Normal deter-
gents may suds too much and can leave laundry that is not completely washed
or rinsed.
Retrofit Options
There are two main retrofit options to reduce water use associated with existing
laundry equipment: water reuse/recycling and ozone systems.
Water Reuse/Recycling
Simple or complex recycling systems can be added to coin- or card-operated wash-
ers, multi-load washers, and washer extractors to recycle a portion or all of the water
for reuse in the next wash. Simple recycling systems recover discharge from the final
rinse in a multi-cycle operation for use in the first rinse of the next cycle. The water
from these systems rarely needs treatment prior to reuse, so potential water savings
is 10 to 35 percent. Complex recycling systems treat the reclaimed water from wash
and rinse cycles for use in all cycles of the next load and can save more than 85 per-
cent of water used. Complex recycle systems usually require water treatment before
Be sure to evaluate space constraints when considering water reuse/recycling op-
tions. Space may not be available to accommodate additional recycling equipment
or storage tanks. Because recycling may also require adjustments in chemicals and
detergents, contact the chemical supply vendor in any retrofit planning.
Ozone Systems
Ozone systems can be installed on all types of existing commercial laundry machines
as retrofits, although they are not as common as a retrofit for tunnel washers. Ozone
systems generate ozone, which is injected into the wash as a powerful oxidant that
reacts with dirt and organic materials. It also provides disinfection and whiten-
ing properties. Ozone can allow for reduced water temperatures, typically to 80
which saves energy. It also can reduce the amount of detergents and other chemi-
cals needed, lessening the amount of rinsing required. Ozone systems work well on
lightly soiled laundry, but they are not recommended for heavily soiled laundry. For
heavily soiled laundry, conventional washing, detergents, and hot water work best.
See Figure 3-3 for an example of the configuration of a laundry ozone system.
Laundry Equipment
East Bay Municipal Utility District (EBMUD). 2008.
WaterSmart Guidebook: A Water-Use Efficiency Plan Review Guide for New Businesses
Page 31.