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1 This presentation is posted for public use. ACEEE does not endorse any product or service. ACEEE accepts no responsibility for any facts or claims this presentation may contain.

2 ACEEE Hot Water Forum 2011 Steven L. Barfuss Utah State University

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4 Accuracy of In-Service Water Meters at Low and High flow Rates Project No Sponsored by The Water Research Foundation Formally known as the AWWA Research Foundation Four Year Project Started: October 2006 Completion Date: October 2010 Final Report Submitted: March 2011

5 RESEARCH COMPONENTS Cold Water New meter accuracies Meter accuracy as a function of throughput Pulled meter accuracies Low and high flow rate accuracies Effect of particulates on accuracy Accuracy tests performed at the new condition, 25%, 50%, 75% and 100% of the meter s expected life.

6 PROJECT ENCOMPASSED.. Meters from 15 US manufacturers 5/8 x 3/4- through 2-inch sizes Wide range of flow rates Involvement of twelve utilities

7 Meters were purchased through local distributors and not directly from the manufacturer Extreme quality control on measurement equipment and procedures (NIST traceability) Data management

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10 METER TYPES ND: Nutating Disc (Positive Displacement) DP: Displacement Piston (Positive Displacement) MJ: Multi-Jet SJ: Single-Jet FO: Fluidic Oscillator TU: Turbine PR: Propeller

11 AWWA Flow Accuracy Standards 5/8 x 3/4 inch Maximum Flow Rate Type Flow (gpm) Upper (%) Lower (%) DP ND FO SJ MJ /8 x 3/4 inch meters

12 AWWA Flow Accuracy Standards 5/8 x 3/4 inch Intermediate Flow Rate Type Flow (gpm) Upper (%) Lower (%) DP ND FO SJ MJ /8 x 3/4 inch meters

13 AWWA Flow Accuracy Standards 5/8 x 3/4 inch Minimum Flow Rate Type Flow (gpm) Upper (%) Lower (%) DP 1/ ND 1/ FO 1/ SJ 1/ MJ 1/ /8 x 3/4 inch meters

14 This research included flow rates above and below the AWWA flow standards, a topic that had not been studied in depth in the past.

15 1/64 gpm 1/32 gpm 1/16 gpm 1/8 gpm 1/4 gpm AWWA low flow for all meters 1/2 gpm 1 gpm AWWA inter. flow for SJ and MJ 2 gpm AWWA inter. flow for DP, ND, FO 15 gpm AWWA high flow for all meters 20 gpm 5/8 x 3/4 inch meters

16 5/8 x 3/4 inch meters

17 5/8 x 3/4 inch meters

18 5/8 x 3/4 inch meters

19 5/8 x 3/4 inch meters

20 5/8 x 3/4 inch meters

21 5/8 x 3/4 inch meters

22 5/8 x 3/4 inch meters

23 5/8 x 3/4 inch meters

24 5/8 x 3/4 inch meters

25 5/8 x 3/4 inch meters

26 5/8 x 3/4 inch meters

27 5/8 x 3/4 inch meters

28 5/8 x 3/4 inch meters

29 5/8 x 3/4 inch meters

30 New Meter Tests: A larger-than-expected percentage of new meters failed one or more of the three AWWA flow accuracy standards. These same meters are reported and advertised to meet the AWWA accuracy standards.

31 One manufacturer was able to meet the AWWA standard at all three flow rates (for new meters in all sizes and types offered) more than 95% of the time. None of the other 14 manufacturers were able to exceed a success percentage greater than 85%. In contrast, a second manufacturer s new meters only met the AWWA standard at all three flow rates 17% of the time. Seven manufacturers only passed all three AWWA standard flow rates 50% of the time or less.

32 Number/percent passing AWWA standard Meter type Low Intermediate Maximum DP (48) 37 77% 43 90% % MJ (42) 32 76% 37 88% 38 90% ND (30) % 27 90% % SJ (24) 18 75% 18 75% 18 75% FO (6) 6 100% 6 100% 6 100% Overall (150) % % % 5/8 x 3/4 inch meters

33 Specific Minimum Flow Pass Rates for Single-Jet Meter Manufacturers Single-Jet Manufacturer A B C D Met Minimum AWWA Flow Total Meters Tested /8 x 3/4 inch meters

34 A study performed in 1999 indicated that homes on average have a leak of 21.9 gpd, while 5.5 % of the homes included in the study leaked more than 100 gpd (AWWARF, 1999)

35 All Homes 152 drips/min 5.5% of all homes Continuous Toilet Leak

36 Endurance Tests: The Multi-Jet, Single-Jet and Piston meters indicated the highest amount of accuracy degradation after a full life cycle of throughput. The Nutating Disc and Fluidic Oscillator meters maintained the highest registries at the lowest flow rates both in the new condition and after a full life cycle of throughput.

37 Meter No. of Test Meters passing AWWA standard at throughput type meters flow 0 MG 0.5 MG 1 MG 1.5 MG 2 MG 5/8x3/4 ND /8x3/4 ND /8x3/4 ND /8x3/4 DP /8x3/4 DP /8x3/4 DP /8x3/4 MJ /8x3/4 MJ /8x3/4 MJ /8x3/4 SJ /8x3/4 SJ /8x3/4 SJ /8x3/4 FO /8x3/4 FO /8x3/4 FO /8 x 3/4 inch meters

38 5/8 x 3/4 inch meters

39 5/8 x 3/4 inch meters

40 5/8 x 3/4 inch meters

41 Pulled Meter Tests: There was no significant correlation between meter performance and throughput or meter performance and age. There was however, a significant number of utilityprovided pulled meters that did not function (~7%)

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43 Particulate Tests: Sand particulates had the greatest affect on the Piston meter type (initially and after throughput). The Nutating Disc and Piston type meters showed accuracy degradation affects at the minimum AWWA flow rate over a full life cycle of throughput. The Piston and Single-Jet type meters showed accuracy degradation affects at the maximum AWWA flow rate over a full life cycle of throughput. Multi-jet and Fluidic Oscillator type meters were the least affected by sand particulates.

44 Pre-Particulate 0-Life Meter Summary 105% 100% 95% Registry 90% 85% 80% / Flow (gpm) DP SJ ND MJ FO

45 Particulate 0-Life Meter Summary 105% 100% 95% Registry 90% 85% 80% / Flow (gpm) DP SJ ND MJ FO

46 Particulate Full-Life Meter Summary 105% 100% 95% Registry 90% 85% 80% / Flow (gpm) DP SJ ND MJ FO

47 Particulate 5/8 x 3/4-inch Multi-jet Registry Summary 110% 100% 90% 80% 70% Registry 60% 50% 40% 30% 20% 10% 0% / Flow (gpm) Before 0 MG 0.5 MG 1.0 MG 1.5 MG 2.0 MG

48 Benefits & Features: Operates up to 194 degrees Fahrenheit Meets All AWWA Standards Tamper Detection and Prevention High Quality, Long Life Parts Durable Basket Strainer Protects From Damage Hot Water Meters - 5/8" to 2" Velocity-type meter meeting or exceeding the performance requirements of AWWA Standard C-708.

49 Hot Water Meters: Meter types are the same as cold water Manufacturers state that metering components are higher quality, but internal working parts look identical

50 Benefits & Features: Operates up to 194 degrees Fahrenheit Meets All AWWA Standards Tamper Detection and Prevention High Quality, Long Life Parts Durable Basket Strainer Protects From Damage Hot Water Meters - 5/8" to 2" Velocity-type meter meeting or exceeding the performance requirements of AWWA Standard C-708. AWWA Standard C-708 is a Multi-jet cold water standard

51 Hot Water Meters: No AWWA standards for hot water meters Consequently, no hot water facility to certify accuracy of hot water meters The State of California was the first to specify hot water standards for sub-metering

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55 The AWWA M6 manual states: All new meters should be tested for accuracy of registration at flow rates and test-flow quantities in accordance with Table 5-3 before they are placed in service. This requirement is an essential component to ensuring that meters placed in the marketplace are operating accurately.

56 Only 65% of the 450 new meters that were purchased came with certificates like this one.

57 End users should ensure that each meter they purchase includes a calibration with a certification that the meter was tested as a complete unit that it was calibrated at each of the required flow rates and that the meter registered flows that met the AWWA requirements.

58 All meters of all types and sizes lose accuracy (at some point) at very low flow rates. Utilities have to balance the cost of technologically advanced meters and the expected revenue from less accurate, more affordable meters.

59 New meters types on the market: Magnetic Ultrasonic New mechanical models Accuracy certification is critical to a system s economic success.

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