ASME A112.1002 pdf download Anti-siphon fill valves for water closet tanks
This Standard covers anti-siphon fill valves intended to be installed in water closet tanks.Note: In this Standard, anti-siphon fill valves are also referred to as “devices”.
In this Standard,” shall””is used to express a requirement, i.e., a provision that the user is obliged tosatisfy in order to comply with the standard; “should” is used to express a recommendation or thatwhich is advised but not required; and “may” is used to express an option or that which is permissiblewithin the limits of the standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of anote accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written asrequirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define theirapplication.
sl units are the units of record in Canada. In this Standard the inch/pound units are shown inparentheses.
The values stated in each measurement system are equivalent in application; however, each system is tobe used independently.Combining values from the two measurement systems can result in nonconformance with this Standard.
All references to gallons are to U.s. gallons.
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 the edition listed below, including all amendments published thereto.
ASME (American Society of Mechanical Engineers)/CSA Group
ASME A112.18.1-2018/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)
ASME B1.1-2003 (R2018)
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, the following definitions shall apply in this Standard:
Anti-siphon fill valve — a valve that is used to supply water for flush tank refill and, where applicable,rap reseal. The device has an air gap, integral mechanical backflow preventer, or vacuum breaker to prevent the backflow of water from the flush tank into the supply system. The device is operated by a float or similar activation method.
Retrofit device — any replacement fill valve not specifically supplied by the original equipment manufacturer of the water closet tank.
The following abbreviation shall apply in this Standard:
CL — critical level
3 Design and general requirements
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
3.3.1 Installed position
The bowl refill tube, when supplied, shall be sufficiently rigid to maintain its installed position.
3.3.2 Retrofit devices only
The means of securing the bowl refill tube shall not obstruct a cross-sectional area of the tank overflow tube by more than 20 mm 2 (0.031 in 2 ).
Note: When a water closet tank is equipped with an anti-siphon fill valve as original equipment, the required overflow 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 to reduce 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, the dimensions of standard shanks or inlets designed to mate with standard coupling nuts or locknuts shall be as specified in Figure 1.
Standard shank or inlet thread dimensions shall be 15/16-14 UNS-1A as specified in ASME B1.1.
Standard coupling nut or locknut thread dimensions shall be 15/16-14 UNS-1B as specified in
Note: The recommended standard major and pitch thread diameters are the following:
a) Nominal shank thread —
i) major diameter: 23.37 to 23.77 mm (0.9204 to 0.9359 in); and
ii) pitch diameter: 22.39 to 22.50 mm (0.8816 to 0.8895 in).
b) Nominal locknut and coupling nut thread —
i) minor diameter: 21.85 to 22.05 mm (0.8602 to 0.8681 in); and
ii) pitch diameter: 22.63 to 22.90 mm (0.8911 to 0.9014 in)