Page 40 - WaterSense at Work

October 2012
Meter Selection
The first step in choosing a meter is to determine its use and select the appropriate
type of meter from the list below:
Positive displacement meters are best suited for small commercial or institutional
applications because they have high accuracy rates at low flows and can precise-
ly measure peak flows.
Compound meters are a good choice for large commercial or institutional
facilities because they accurately measure low flows and high flows with their
multiple-measuring chamber design.
Turbine and propeller meters are most appropriate for continuous, high-flow
applications and are inaccurate at low flows. These types of meters are not usu-
ally recommended for commercial, institutional, or residential buildings because
water flows are in constant fluctuation, with very low minimum flow rates.
Next, select the appropriate size of the meter. It is critical to understand the build-
ing’s size, function, fixture types, usage occupancy, and peak population in order to
select the appropriately sized meter. These statistics determine the minimum and
maximum flow rates and will assist in the selection of a properly sized water meter.
AWWA Manual M22,
Sizing Water Service Lines and Meters
provides additional guide-
lines for selecting and sizing utility-owned and installed water meters.
Meter Installation and Maintenance
After selecting a meter, consider the following installation and maintenance best
practices to ensure optimal meter operation:
When installing a meter, follow the manufacturer’s instructions. Improper instal-
lation can lead to metering inaccuracies.
Install meters in an accessible location to allow for reading and repair. In addition,
ensure that the meter location is protected from potential damage.
Metering and Submetering
Submeter Application
Alternative Water
Meter water use from alternative water sources, such as
gray water, rainwater, air handler or boiler condensate, or
other sources discussed in
Section 8: Onsite Alternative Water
Other Processes
Meter any other process with a projected annual water use
of 100,000 gallons or more.
Table 2-1. Submetering Recommendations (cont.)
op. cit
American Water Works Association (AWWA). 2004.
Sizing Water Service Lines and Meters
AWWA Manual M22, Second Edition).