Resources
Here you will find a large selection of resources provided by backflow direct that will help you discern the correct installation and maintenance methods for many if not all of our products here. Each file present here centers around backflow prevention installation and the necessary steps needed to have the most optimal installation and ensure your new addition runs smoothly for years and years to come. If for whatever reason you don’t find the answer among these files, please don’t hesitate to give us a call as soon as possible. When it comes to backflow prevention installation, we want to be there for each and every one of our customers to ensure they’re projects are going smooth and steady. Browse our documents or give us a call today!
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Specification Sheets
Deringer Specification Sheets include information on valve characteristics, flow performance data, approval status and engineering specifications for all sizes.
Deringer 20 Specification Sheet
Deringer 20X Specification Sheet
Deringer 30 Specification Sheet
Deringer 30X Specification Sheet
Deringer 40 Specification Sheet
Deringer 40X Specification Sheet
Deringer 50 Specification Sheet
Deringer 50X Specification Sheet
Deringer 20G Specification Sheet
Deringer 20GX Specification Sheet
Deringer 30G Specification Sheet
Deringer 30GX Specification Sheet
Deringer 40G Specification Sheet
Deringer 40GX Specification Sheet
Deringer 50G Specification Sheet
Deringer 50GX Specification Sheet
Maintenance Instructions
Deringer Maintenance Instructions provide step by step procedures for maintaining your backflow preventer.
Deringer 20/30 2 to 4 inch Maintenance Instructions
Deringer 20/30 6 to 8 inch and 20X/30X 4 to 6 inch Maintenance Instructions
Deringer 40/50 2 to 4 inch Maintenance Instructions
Deringer 40/50 6 to 8 inch and 40X/50X 4 to 6 inch Maintenance Instructions
Deringer 20G/30G 2 to 4 inch Maintenance Instructions
Deringer 20G/30G 6 to 8 inch and 20X/30X 4 to 6 inch Maintenance Instructions
Deringer 40G/50G 2 to 4 inch Maintenance Instructions
Deringer 40G/50G 6 to 8 inch and 40GX/50GX 4 to 6 inch Maintenance Instructions
Maintenance Videos
Maintenance Video - 2 to 4" Deringer 20
Maintenance Video - 6 to 8" Deringer 20(X)
Maintenance Video - 2 to 4" Deringer 30
Maintenance Video - 4 to 8" Deringer 30(X)
Maintenance Video - 2 to 4" Deringer 40
Maintenance Video - 4 to 8" Deringer 40(X)
Maintenance Video - 2 to 4" Deringer 50
Maintenance Video - 6 to 8" Deringer 50(X)
Maintenance Video - 2½ to 8" Shut Off Valve
Relief Valve Discharge Rates
Discharge rates for relief valves of RP and RPDA backflow assemblies including Deringer/Magnum 40/40G, 50/50G, 40X/40GX, 50X/50GX.
Deringer/Magnum RP/RPDA Relief Vale Discharge Rates
Tamper Switch Procedure
The Deringer Gear Box Tamper Switch Procedure provides a step by step instructions for positioning the wiring of the Deringer gear box for fire alarm protection.
Gear Box Wiring & Replacement Instructions
The Deringer Gear Box Wiring Installation Instructions provide step by step procedures for wiring the Deringer gear box for fire alarm protection.
Indicator Flag Adjustment
The Indicator Flag Adjustment Instructions provide a step by step procedure for aligning the flag to fully open and fully close on the backflow preventor gear box.
Bypass Testing Instructions
Video: About the Type II Bypass
CAD File Downloads
REVIT File Downloads
Approvals
Certified Backflow Preventers
At Backflow Direct, we pride ourselves on providing durable, reliable, and lightweight certified backflow preventers suited for your fire protection applications, as well as replacement parts that are of the highest quality. This is evidenced by the many certifications our products have received from third-party certification organizations, such as Underwriters Laboratories (UL), Underwriters Laboratories Canada (ULC), the Foundation for Cross Connection (USC), Factory Mutual (FM), and the American Society Sanitary Engineers (ASSE). Our products are also NSF/ANSI 372 certified, which ensures that our products are lead-free.
We’ve worked hard for the many safety certifications and approvals our certified backflow preventers and replacement parts have received. UL approval, for example, ensures that our products have been field tested and are durable, reliable, and safe to use. To learn more about the specific certifications our products have, you can refer to the individual product’s specification sheets.
UL Underwriters Laboratories - Deringer Listed Models
| Size | DC Horizontal | DC Vertical | DCDA-II Horizontal | DCDA-II Vertical | RP | RPDA-II |
| 2-1/2" | 20 | 20 | 30 | 30 | 40 | 50 |
| 3" | 20 | 20 | 30 | 30 | 40 | 50 |
| 4" | 20 | 20 | 30 | 30 | 40 | 50 |
| 6" | 20x | 20x | 30x | 30x | 40x | 50x |
| 8" | 20 | 20 | 30 | 30 | 40 | 50 |
| Listed | Fully Approved Click Here for Online Certification |
ULC Underwriters Laboratories Canada - Deringer Listed Models
| Size | DC Horizontal | DC Vertical | DCDA-II Horizontal | DCDA-II Vertical | RP | RPDA-II |
| 2-1/2" | 20 | 20 | 30 | 30 | 40 | 50 |
| 3" | 20 | 20 | 30 | 30 | 40 | 50 |
| 4" | 20 | 20 | 30 | 30 | 40 | 50 |
| 6" | 20x | 20x | 30x | 30x | 40x | 50x |
| 8" | 20 | 20 | 30 | 30 | 40 | 50 |
| Listed | Fully Approved Click Here for Online Certification |
FM Factory Mutual - Deringer Approved Models
| Size | DC Horizontal | DC Vertical | DCDA-II Horizontal | DCDA-II Vertical | RP | RPDA-II |
| 2-1/2" | 20 | 20 | 30 | 30 | 40 | 50 |
| 3" | 20 | 20 | 30 | 30 | 40 | 50 |
| 4" | 20 | 20 | 30 | 30 | 40 | 50 |
| 6" | 20x | 20x | 30x | 30x | 40x | 50x |
| 8" | 20 | 20 | 30 | 30 | 40 | 50 |
| Approved | Fully Approved Click Here for Online Certification |
USC Foundation for Cross Connection - Deringer Approved Models
| Size | DC Horizontal | DC Vertical | DCDA-II Horizontal | DCDA-II Vertical | RP | RPDA-II |
| 2-1/2" | 20 | 20 | 30 | 30 | 40 | 50 |
| 3" | 20 | 20 | 30 | 30 | 40 | 50 |
| 4" | 20 | 20 | 30 | 30 | 40 | 50 |
| 6" | 20x | 20x | 30x | 30x | 40x | 50x |
| 8" | 20 | 20 | 30 | 30 | 40 | 50 |
| Approved | Fully Approved Click Here for Online Listings |
| Approved | Fully Approved Click Here for Actual Certification |
ASSE American Society Sanitary Engineers - Deringer Listed Models
| Size | DC Horizontal | DC Vertical | DCDA-II Horizontal | DCDA-II Vertical | RP | RPDA-II |
| 2-1/2" | 20 | 20 | 30 | 30 | 40 | 50 Evaluation Complete |
| 3" | 20 | 20 | 30 | 30 | 40 | 50 Evaluation Complete |
| 4" | 20 | 20 | 30 | 30 | 40 | 50 Evaluation Complete |
| 6" | 20x | 20x | 30x | 30x | 40x | 50x Evaluation Complete |
| 8" | 20 | 20 | 30 | 30 | 40 | 50 Evaluation Complete |
| Evaluation Complete | All laboratory evaluation has been successfully completed and final documentation/certification is in process. |
| Listed | Fully Approved Click Here for Certification |
NSF/ANSI 372 Lead Free Certification - Deringer Certified Models
| Size | DC Horizontal | DC Vertical | DCDA-II Horizontal | DCDA-II Vertical | RP | RPDA-II |
| 2-1/2" | 20 | 20 | 30 | 30 | 40 | 50 |
| 3" | 20 | 20 | 30 | 30 | 40 | 50 |
| 4" | 20 | 20 | 30 | 30 | 40 | 50 |
| 6" | 20x | 20x | 30x | 30x | 40x | 50x |
| 8" | 20 | 20 | 30 | 30 | 40 | 50 |
| Certified | The wetted surface of this product, contacted by consumable water, contains less than 0.25% lead by weight. Per Safe Drinking Water Act 1-4-14 Requirements. Certified by Underwriters Laboratories (UL). Fully Approved Click Here for Online Certification |
SS705 Shut-off Valve
| Size | UL 1091 | FM 1112 | USC 10th Edition |
| 2-1/2" | Listed | Approved | Evaluation in Process |
| 3" | Listed | Approved | Evaluation in Process |
| 4" | Listed | Approved | Evaluation in Process |
| 6" | Listed | Approved | Evaluation in Process |
| 8" | Listed | Approved | Evaluation in Process |
| Evaluation In Process | Product is currently undergoing laboratory evaluation. |
| Evaluation Complete | All laboratory evaluation has been successfully completed and final documentation/certification is in process. |
| FM Approved | Fully Approved Click Here for Online Certification |
| UL Listed | Fully Approved Click Here for Online Certification |