Model 855

5 Valve Digital Backflow Test Kit

Introducing the Future of Backflow Testing: The Digital Backflow Testing Device!

Say goodbye to manual paperwork and hello to efficiency and accuracy with our revolutionary Digital Backflow Test Kit!

Precision at Your Fingertips: Our device utilizes state-of-the-art digital technology to ensure precise and reliable backflow testing results every time.

Streamlined Workflow: With intuitive digital interfaces and automated data logging, our device simplifies the entire testing process from start to finish. Spend less time on paperwork and more time serving your customers.

Comprehensive Reporting: Generate detailed reports instantly, complete with digital signatures.

Built to Last: Crafted from proven materials and backed by our commitment to quality, the model 855 Digital Backflow Test Kit is built to withstand the rigors of daily use, ensuring long-lasting performance and reliability.

Functions and Applications:
The model 855 kit provides the capability for testing all brands of reduced pressure principle, pressure vacuum breaker and double check valve backflow prevention assemblies.

∆P Range: 0-15 PSID, Pressure sensor 0-200 PSIG

Basic Features:   (Included with activation)

  • Read ΔP and line pressure digitally on your phone.
  • Record test values with capture buttons or toggle switches.
  • Test fields change based on the assembly type selected.
  • Special program for capturing PVB air inlet opening point.
  • Saves all tests results to the cloud.
  • App works on Wi-Fi, Cellular, or Offline when no signal.
  • Sort, filter and search saved test results.

Premium Features:   (Requires subscription after 30 days)

  • Autofill customer & assembly information by searching previously tested assemblies.
  • Download the day’s test data into a .csv spreadsheet for easy review or upload the completed tests to another program.
  • Generate PDFs to save, share, or e-mail.

Want to see the machbackflow app in action?    Watch this video: App Overview Video

  • Model 855 requires activation of the Machbackflow app on your IOS or Android device.   
  • Basic app features included for the life of the kit.
  • Premium features included for first 30 days after activation.   
  • Annual subscription to Premium  app can be purchased from
  • Mobile device not included with purchase of test kit 
  • Lead time is 7-10 business days after receipt of order confirmation.


Product Features/Benefits

  • Advanced Digital Technology: Enjoy all the functionality and accessories of the popular Model 845, enhanced with cutting-edge digital features for improved performance and efficiency.
  • Seamless Mobile Integration: Utilize Bluetooth connectivity to sync with your mobile device, allowing you to view test data directly on the user-friendly Machbackflow iOS or Android App.
  • Effortless Data Management: Build and maintain a comprehensive database of customers and assemblies with the Machbackflow app, ensuring easy access to previous tests, repairs, and other vital data whenever you need it.
  • Tailored for Backflow Prevention Testing: Specifically designed to meet the unique requirements of testing backflow prevention assemblies, providing reliable and accurate results every time.
  • Consistent Testing Standards: Utilize the same case, hoses, and fittings as the Model 845 analog test kit, ensuring consistency and familiarity for users transitioning to digital technology.
  • Easy to use: Identical valve configuration to the industry leading model 845-5 test kit.
  • Convenient Storage and Portability: Carry and organize your test kit with ease using the durable molded plastic carrying case, complete with integrated storage compartments for fittings and tools. The portable unit is removable from the case, featuring a removable strap and cell phone holder for optimal accessibility during tests.
  • Enhanced Durability and Performance: Equipped with 90-micron filters to minimize plugging from scale, sand, and other debris, ensuring reliable performance even in challenging conditions. Filter elements can be easily cleaned or replaced as needed.
  • Basic App Access: Machbackflow app activation and lifetime access to the apps basic features is included for the life of the test kit. ($350 value - Included in sales price)
  • Premium App Access: Enjoy one month of trial subscription to premium app features upon activation, enhancing your testing experience with additional functionalities.
  • Long-Term Reliability: Rest assured with a comprehensive 5-year warranty, providing peace of mind and ensuring continued support for your investment.


  • Gauge Type Capacitive Differential Pressure Sensor
  • Differential Pressure Accuracy ± .2 P.S.I.D.
  • Working Pressure: 200 PSIG
  • Body Material: Glass Reinforced Engineering Thermoplastic
  • Wetted Internals: EP Elastomers, Brass and 316 S.S. Metal Parts
  • Piezoresistive Line Pressure Sensor 0-200 PSIG
  • Rechargeable Lithium Ion Battery
  • Soft-Seated Brass Needle Valves (with replaceable valve seats)
  • Hoses with Inline Filters & Schrader ¼” brass coupler End Fittings
  • Hose Length: Three (3) each / 5' long (color-coded)
  • Bleed Tube, One each / 4' long clear bleed tube.
  • Adaptor Fittings: (3) sets of brass fittings provided for hookup to all standard size test cocks
  • Gauge Weight: 3.6lbs / 1.6kg
  • Case: Durable Molded Plastic
  • Size: 18 1/2"L x 9"W x 9 3/4"H
  • Temperature Limitations: Maximum 150°F/65°C


It is capable of performing all known test procedures including those recommended by ASSE, AWWA, CSA, FCCC and HR-USC and NEWWA.

The Mid-West Advantage