WaterSense Specification for Showerheads. ACEEE Hot Water Forum

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1 WaterSense Specification for Showerheads ACEEE Hot Water Forum

2 Meeting Agenda Introduction to WaterSense Showerheads Background and Specification Development Process WaterSense Specification for Showerheads Other Considerations 2

3 WaterSense Product Evaluation Factors WaterSense uses the following factors in determining which products to label Products must: Offer equivalent or superior performance Be about 20 percent more water-efficient than conventional models Realize water savings on a national level Provide measurable results Achieve water efficiency through several technology options Be effectively differentiated by the WaterSense label Be independently certified 3

4 Showerhead Background The federal regulation and existing standards set the maximum flow rate at 2.5 gpm at 80 psi, but do not address performance The WaterSense label means water-efficiency and performance WaterSense needed to determine what characteristics are important to users and how to test those in a laboratory 4

5 Showerhead Specification Development Process WaterSense collaborated with the ASME/CSA joint harmonization task force on water-efficient showerheads Initial key performance attributes identified included: Flow rate verses pressure Temperature drop Water distribution (shape of cone, volume and area of distribution) Droplet size Water stream (spray exit velocity) 5

6 Showerhead Specification Development Process WaterSense conducted user satisfaction testing to: Determine if users uniformly liked or disliked certain showerheads Confirm which characteristics were important to users Establish minimum acceptable performance levels 6

7 Showerhead Specification Development Process Study participant profiles 20 males, 17 females Ages: % short hair, 50% medium and long hair 20% curly/wavy hair, 80% straight hair 50% thick hair, 50% medium or thin hair 7

8 Showerhead Flow Rate Temp Force Coverage Rinse % No Buy S 2.5 0% R % L % M % V % E % K 1.6 X 40% Q % U 1.5 X 57% N % O % H 2.5 X 63% A 2.5 X X 67% F 1.0 X X X 71% I 2.5 X X 75% C 0.7 X X X 83% G 1.5 X X X 83% P % J 2.5 X X X 83% T 1.5 X X X 100% 8 B 2.0 X X X X 100% D %

9 Showerhead Specification Development Process The task force developed laboratory test protocols to measure the important characteristics: Pressure compensation Effectiveness (force of the shower spray) Spray pattern/distribution 9

10 WaterSense Specification for Showerheads Applies to: Fixed showerheads Hand-held showerheads Multiple showerheads (with exceptions) Does not apply to: Body sprays or retrofit devices, including flow control devices 10

11 WaterSense Specification for Showerheads Water-Efficiency The maximum flow rate shall be the highest value obtained through testing at flowing pressures of 20, 45, and 80 psi and shall not exceed 2.0 gpm 11

12 WaterSense Specification for Showerheads Performance: Pressure compensation At a flowing pressure of 20 psi the tested flow rate must be at least 60 percent of the maximum flow rate At flowing pressures of 45 and 80 the lowest tested flow rate must be at least 75 percent of the maximum flow rate 12

13 Performance Criteria: Spray Force Performance: Force Minimum spray force must be at least 2.0 ounces at a pressure of 20 psi at the inlet when water is flowing 13

14 WaterSense Specification for Showerheads Performance: Spray Coverage Total combined water volume collected in the: 2- and 4-inch rings cannot exceed 75 percent of the total water volume collected 2-, 4-, and 6-inch rings cannot be less than 25 percent of the total water volume collected 14

15 Other Considerations 1. Reducing showerhead flow rates may increase the risk of thermal shock and scalding Automatic-compensating mixing valves required by code are currently only certified at a flow rate of 2.5 gpm at 45 psi Problems persist Vales are not currently tested at lower flow rates Older homes may not have the appropriate mixing valves 15

16 Other Considerations To address this health and safety issue WaterSense: Is requiring manufacturers to mark product packaging with the minimum flow rate at 45 psi to assist consumers in matching showerheads and mixing valves Plans to continue working with ASSE and ASME to revise the existing standards for mixing valves to ensure their compatibility in terms of both tested pressure and flow rates 16

17 Other Considerations 2. Users may increase water temperature to compensate for heat loss Temperature drop is indirectly addressed by the specification s performance criteria Further, users could theoretically increase hot to cold water ratio from 73% (current average) to 91% (an 18% increase) and still achieve a slight energy savings with a WaterSense labeled showerhead 17

18 A Shower of Savings Water savings 1,200 gallons per showerhead or 2,300 gallons per household per year 250 billion gallons per year with nationwide adoption Energy savings 300 kwh or electricity or 1,500 cubic feet of natural gas per year 14 billion kwh of electricity and 94 million cubic feet of natural gas per year with nationwide adoption Cost effectiveness A WaterSense labeled showerhead will pay for itself in just over a year 18

19 More Information Web site: Helpline: (866) WTR-SENS ( ) 19