The 4 inch Deringer 20GX Double Check Valve Assembly is designed to prevent non-health hazard pollutants from potable water supply systems due to backpressure and backsiphonage. This low head loss assembly features a durable 304 stainless steel housing and patented Dual-action check modules for consistent performance at both low and high flow rates. It includes inline serviceable OS&Y gate valves, tamper-resistant test cocks, and utilizes ANSI B16.1 Class 125 flanged end connections. Rated for 10-175 psi and 33°F-140°F, it is UL Classified, FM Approved, ASSE 1015, and NSF/ANSI 372 compliant. Item number D-4020GX.
Help Me Connect
End Connections
The assembly features flanged ends compliant with ANSI B16.1 Class 125 for secure pipeline integration.
Flexible groove couplings, UL/FM approved, are present between the body and the gate valves, facilitating connection and maintenance.
The 4 inch Deringer™ 20GX Low Head Loss Double Check Valve Assembly is designed to prevent non-health hazard pollutants from entering the potable water supply system caused by backpressure and/or backsiphonage conditions.
This assembly features an extra-large body and checks for lower head loss, enabling high performance for both low and high-flow rates. It is approved for continuous pressure service and suitable for horizontal or vertical installations.
Features
Oversized checks for extreme performance and lower head loss
Inline serviceable OS&Y gate valves for shutoff
Robust stainless steel housing construction
Tamper-resistant test cocks for secure testing
Patented Dual-action™ check modules operate with poppet action at low flow and swing action at high flow
Flexible groove coupling UL/FM between body and gate valves
Specifications
Model: 20GX
Product Size: 4 inch
Product Type: Double Check Valve Assembly (DC)
Head Loss: Low Head Loss
Lead Free: Yes (wetted surfaces contain less than 0.25% lead by weight)
Serviceable: Inline Serviceable
Installation Orientation: Horizontal or Vertical
Materials
Valve Housing: 304 Stainless Steel
Valve Cover: 304 Stainless Steel
SOV Disks: EPDM/304SS
SOV Shafts: 304 Stainless Steel
SOV Bearings: Teflon® fluoropolymer/Bronze
Non-wetted Bolts: Grade 8 Zinc Plated
Check Disks: Silicone (NSF)
Wetted Fasteners: 18-8 Stainless Steel
Check Springs: 17-7 Stainless Steel
Check Pins: 17-7/18-8 Stainless Steel
Check Seats: Noryl® Polymer (NSF)
O-rings: Buna-N (NSF)
Pressure & Temperature
Temperature Range: 33°F - 140°F
Working Pressure: 10-175 psi
End Connections
Flange Connections: ANSI B16.1 Class 125
Dimensions (4 inch)
Overall Height (Ht): 22.5 inches (572 mm)
Centerline to Bottom (Hb): 4.5 inches (114 mm)
Length (L): 36.9 inches (937 mm)
Height to Top of Handwheel (Ht+Hb): 27.0 inches (686 mm)
Width (W): 12.0 inches (304 mm)
Weight: 160 lbs (73 kg)
Certificates & Approvals
AWWA C510-07 Compliant
NSF/ANSI 372
UL Certified
UL Classified
FM Approved
ASSE 1015
USC Approved
FAQs
What is the primary function of the Deringer 20GX Double Check Valve Assembly?
The Deringer 20GX Double Check Valve Assembly is designed to prevent non-health hazard pollutants from entering potable water supply systems, specifically due to backpressure and backsiphonage conditions.
What type of connections does this 4-inch valve assembly use?
This assembly uses flanged end connections that conform to ANSI B16.1 Class 125 standards.
What are the key material components of the Deringer 20GX?
The valve housing and cover are constructed from 304 Stainless Steel. Check discs are made of Silicone (NSF), check seats from Noryl® Polymer (NSF), and O-rings from Buna-N (NSF).
What is the maximum working pressure and temperature range for this backflow preventer?
The maximum working pressure for the Deringer 20GX is 175 psi. It operates effectively within a temperature range of 33°F to 140°F.
Is the Deringer 20GX certified by recognized organizations?
Yes, it is AWWA C510-07 Compliant, NSF/ANSI 372, UL Certified, UL Classified, FM Approved, ASSE 1015, and USC Approved. It also meets lead-free requirements.
