Backflow prevention keeps potable water safe by stopping contaminants from reversing into the main supply when system pressure drops. A pressure drop can occur for many reasons, including a broken water main¹ or a fire that draws large volumes from hydrants. The safeguard is a backflow preventer that closes when upstream pressure falls so water cannot travel in the wrong direction.
Annual Testing and Certified Service
To keep that protection reliable, the assembly should be tested each year by a certified professional² who verifies valve operation, checks readings on the test gauge, and inspects for leaks or damage. Cleaning and lubricating per the manufacturer’s guidance helps preserve smooth operation and stable results.
How We Help You Choose the Right Kit
If you are looking for the right test kit, we can help you choose and connect with a distributor that fits your location and needs. We are headquartered in Michigan and support customers across North America, the United Kingdom, and Australia. Our long history in backflow field testing means you get practical guidance on kit selection, maintenance, and documentation so your reports are accepted and your workflow runs smoothly.
Proven Backflow Testing Kits
Our product line started with the Model 830, the original Mid-West Instrument backflow test kit that set the benchmark more than 30 years ago. Continuous feedback from customers and our internal test team led to steady refinements, including inline particulate filters that resist plugging from scale or sand, laminated procedures that hold up in the field, removable lids for easier access, soft seated needle valves for precise control, and line pressure gauges for safer setup. We then introduced the portable Model 835, followed by the Model 845, which brings the same core reliability with updated ergonomics and accuracy enhancements. The 845 is available in 5-valve, 3-valve, and 2-valve configurations to match your preferred testing method. Industry groups including FCCC, HR-USC, and CA-NV AWWA list our 845-5, 845-3, and 845 among acceptable gauges, alongside our landmark Model 830.
Recommended Instruments and Key Features
For day-to-day backflow prevention work, we often recommend our diaphragm type instruments Model 845-5 and 835 with bottom and vent connections. Use them to measure system differential pressure and evaluate backflow prevention assemblies with repeatable, defendable results. Our test kits include protective 90 micron filters with cleanable or replaceable elements, clear laminated test procedures that resist moisture, and rugged field cases. The Model 830 is permanently mounted in a double-walled case with a total weight near 14 pounds and permanently affixed hoses. The 835 and 845 are lighter, use removable hoses, and carry a lower service cost because the components are not permanently mounted. If you prefer a standard five-valve method, both 830 and 835 fit that need. If you want flexibility, the 845 offers two, three, or five-valve options so you can match the kit to your training and local program requirements.
Distributor Network and Support
Wherever you work, we can connect you with a knowledgeable distributor. In the United States we partner with trusted teams such as Test Gauge Inc. and Backflow Parts USA. In Canada we have coverage across multiple provinces, and in the UK and Australia our partners include ABLE Instruments & Controls, Backflow Central, and CMC Technologies. Tell us where you are and what your utility or authority requires, and we will point you to the right distributor and the right kit so you can start testing with confidence.
Start Testing With Confidence
For dependable backflow testing and compliant results, trust Mid-West Instrument. We design and build durable, accurate kits and provide the documentation and distributor support that keep your program on track. Contact us for help selecting between the 830, 835, and 845 families and for guidance on annual testing practices that protect customers and communities. Since 1958, Mid-West Instrument has been a leading provider of premium differential pressure gauges. Need help finding the right pressure gauge and equipment for your business? Reach out to us today to speak with one of our experienced professionals
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