1.2.1 Description
These devices are cold water supply valves that are installed within water closet tanks to provide
tank refill and a trap reseal after flushing a water closet. They are equipped with backflow
prevention devices or an air gap.
1.2.2 Working Pressure
The device shall be designed to operate at a minimum pressure range of 20.0 psi to 125.0 psi static
(137.9 kPa to 861.9 kPa).
1.2.3 Capacity - Total Fill and Refill
1.2.3.1 Original Equipment Manufacturer
When the device is furnished as original equipment with a manufacturer’s water closet, the total
flow capacity shall be sufficient to assure proper operation of the fixture in accordance with the
performance standard, ASME A112.19.2. The device shall deliver a fill rate through the refill orifice
as required by the water closet manufacturer.
1.2.3.2 Retrofit Use
When the device is furnished to retrofit water closets, the device shall deliver a minimum flow rate
at 15.0 psig (103.4 kPa) flowing pressure of 1.5 GPM (5.7 L/min), and a minimum refill flow rate,
through the refill orifice, of 20% of the total fill rate at 15.0 psi (103.4 kPa) flowing pressure.
1.2.4 Leakage and Spray Containment
The device shall not spray or otherwise leak water to the outside of the water closet tank during
operation.
1.2.5 Backflow Prevention
The device shall be equipped with a means to prevent backflow due to back siphonage. Air inlet
ports shall be protected in such a manner as to reduce the risk of the intake of foreign material
into the device.
1.2.6 Refill Tube
A means shall be provided to secure the refill tube in its installed position.
1.2.7 Dimensional Criteria for Fill Valve Components
Dimensions for shanks, coupling nuts and locknuts shall be as shown in Figure 1. Thread
dimensions shall be 15/16-14 UNS-1 per ASME/ANSI B1.1. See Appendix A.