Listing Evaluation Criteria for Backflow Preventer and Automatic Boiler or Chiller Filling Device with Pressure Regulating Management
|Publication Date:||1 January 2021|
Devices incorporate two independent check valves in series separated by a means of discharging to a drain by way of a valve and air gap, a means to automatically control flow based on a pressure range, and a means of atmospheric venting to allow drainage. Devices shall only be installed in the Inlet vertical up- outlet vertical down (VUVD) orientation. Check valves shall be force-loaded to a normally closed position.
NOTE: A device conforming with Figure 1 uses a configuration similar to an ASSE 1012 device, with additional subcomponents. The combination of check valves C1 and C2 along with solenoid S2, the float vent valve, and air gap comprise an assembly similar to a backflow preventer with intermediate atmospheric vent.
Minimum Flow Capacity
The device shall be able to flow at minimum 3.7 US gal/min (14 l/min) at a flowing pressure of 30 psi (207 kPa).
The device shall be designed for a maximum incoming line pressure of 100 psi (689 kPa).
The device shall be designed for a maximum incoming water temperature of 140 °F (60 °C).
Size and Connections
Connections shall be in compliance with the standards referred to in local plumbing codes.
Pipe threads shall comply with one of the following standards
a. ASME B1.20.1 NPT or NPSM,
b. ASME B1.20.3 dryseal,
c. ASME B1.20.7 hose threads, or
d. ISO 228 G1/2 threads
The device shall comply with the appropriate electrical requirements of UL 60730-1 or BS EN 60730-2-9, or comply with the applicable requirements of UL 1951. The maximum power consumption during system fill or refill shall be less than 50 W.
Air Gap Fittings
Integral air gap devices shall comply with ASME A112.1.3.