ASME A112.1002 pdf download Anti-siphon fill valves for water closet tanks
2 Reference publications and definitions
2.1 Reference publications
This Standard refers to the following publications, and where such reference is made, it shall be to theedition listed below, including all amendments published thereto.
ASME(American Society of Mechanical Engineers)/CSA GroupASMEA112.18.1-2018/CSA B125.1-18
Plumbing supply fittings
ASME A112.19.2-2018/CSA B45.1-18
Ceramic plumbing fixtures
ASME(American Society of Mechanical Engineers)
Unified Inch Screw Threads,(UN and UNR Thread Form)
ASSE Plumbing Dictionary, Sixth Edition, 2007
In addition to the definitions in ASME A112.18.1/CSA B125.1 and the ASSE Plumbing Dictionary, thefollowing definitions shall apply in this Standard:
Anti-siphon fill valve – a valve that is used to supply water for flush tank refill and, where applicabletrap reseal. The device has an air gap, integral mechanical backflow preventer, or vacuum breaker toprevent the backflow of water from the flush tank into the supply system. The device is operated by afloat or similar activation method.
Retrofit device – any replacement fill valve not specifically supplied by the original equipmentmanufacturer of the water closet tank.
The following abbreviation shall apply in this Standard:
CL – critical level
3 Design and generalrequirements
Devices shall be designed to function at a supply pressure range of 140 to 860 kPa (20 to 125 psi)
Devices shall be designed to function at a temperature range of 5 to 49 “C (40 to 120 “F).
3.3 Bowl refill tube
3.31 Installed position
The bowl refill tube, when supplied, shall be sufficiently rigid to maintain its installed position.
3.3.2 Retrofit devices onlyThe means of securing the bowl refill tube shall not obstruct a cross-sectional area of the tank overflowtube by more than 20 mm2(0.031in2).
Note: When a water closet tank i equipped with an anti-siphon fill valve as original equipment, the requiredoverflow performance is determined in accordance with ASME A112.19.2/CSA B45.1.
3.4 Backflow prevention
The device shall be equipped with a means to prevent backflow. Air inlet ports shall be protected toreduce the risk of the intake of foreign material into the device.
3.5 Dimensional criteria for fill valve components – End connections
Except when proprietary (i.e, non-standard) shanks or inlets are provided by the manufacturer, thedimensions of standard shanks or inlets designed to mate with standard coupling nuts or locknuts shallbe as specified in Figure 1.
Standard shank or inlet thread dimensions shall be 15/16-14 UNS-1A as specified in ASME B1.1.