WaterSense at Work: Best Management Practices for Commercial and Institutional Facilities
Commercial dishwashers are one of the largest water users in commercial kitchens.
They clean and sanitize plates, glasses, bowls, utensils, and other food service ware.
These machines can account for more than one-third of the overall water use in a
Commercial dishwasher design can vary greatly by application,
depending on the how many employees, visitors, and/or customers are served by the
commercial kitchen (i.e., the amount of facility throughput).
The most efficient commercial dishwashers reuse water from
one wash load to the next, using one or more holding tanks.
This not only reduces water use, but also reduces the amount
of energy required to heat additional water. Alternatively, fill-
and-dump commercial dishwashers discard water after each
load, making this type of commercial dishwasher inherently
The basic design of commercial dishwashers varies. Commer-
cial dishwasher design can be separated into several catego-
Stationary door- or hood-type
Smaller facilities serving fewer than 60 people per day often
use undercounter dishwashers, which are similar to residential
dishwashers and tend to be smaller in size.
Stationary door- or hood-type commercial dishwashers are used for slightly larger
throughputs of 150 people per day. These are usually manually front-loaded with
racks (generally 20 inches by 20 inches in size) that contain dishes and other kitchen-
Conveyor-type machines also wash dishes that are manually loaded on removable
racks; however, multiple racks can be washed at a time, and the racks are pulled
through the washer using a conveyor to complete each cycle. The conveyor is typi-
cally turned off between loads. These types of machines are ideal for larger service
facilities serving up to 300 people per day.
Flight-type machines are used in facilities with the highest throughputs. They also
use a conveyor, but instead of loading racks full of dishes onto the conveyor, the
conveyor itself serves as a rack, and dishes are loaded onto the pegs or fingers of the
conveyor rack as it comes around. The conveyor is typically continuously moving as
dishes are loaded, washed, and removed.
Stationary hood-type dishwasher
Alliance for Water Efficiency. Commercial Dishwashing Introduction.
Koeller and Company and H.W. (Bill) Hoffman & Associates, LLC. June 2010.
A Report on Potential Best Management Practices—Commercial Dishwashers
for the California Urban Water Conservation Council.