What Does A Backflow Test Do?

Backflow testing checks a backflow prevention device to ensure it’s working correctly and that water is flowing in only one direction. If you’ve received a test notice from your water provider or you’re responsible for a commercial property, you’ve likely seen this phrase before.

Here’s what it actually means, why it matters in San Diego, and how our Backflow Testing San Diego experts at Atlas Backflow Services make the process simple.

Understanding Backflow and Why Testing Is Required

Backflow is the unwanted reversal of water flow in a plumbing system. Instead of clean water moving from the public main into your property, pressure changes can push used or contaminated water back toward the public supply.

Cross-connections like irrigation systems, fire sprinklers, soda machines, boilers, and commercial processes can all introduce pollutants or contaminants if backflow prevention isn’t working.

Backflow testing is the only reliable way to confirm that your backflow prevention assembly is protecting drinking water by allowing water to flow in one direction only. San Diego-area water providers require periodic testing—often annually—by a certified tester and the submission of official test results.

This protects your property and your neighbors by keeping the public water safe.What a backflow test actually checks

A certified tester uses calibrated gauges and valves to verify the performance of the internal components of your backflow prevention assembly. Depending on the type of assembly you have, the test verifies:

• Directional flow: Water moves only from the supply side to the property side—never backward.

• Check valves: Spring-loaded check valves must close tightly to prevent reverse flow and maintain minimum required differential pressure.

• Relief valves (on RP/RPZ assemblies): The relief valve must open at the correct differential to discharge any backflow and then reseat properly.

• Air inlets (on PVBs/SVBs): Air inlets must open and close at the correct times to break any siphon.

• Shutoff valves: Test confirms upstream and downstream shutoff valves operate and seal.

In short, the test proves the assembly creates a reliable barrier against backflow under normal and backpressure or backsiphonage conditions.

Common Types of Backflow Prevention Devices We Test

• Double Check Valve Assembly (DC or DCVA): Two spring-loaded checks in series. Common for fire sprinklers without chemicals and some commercial services.

• Reduced Pressure Principle Assembly (RP or RPZ): Two checks plus a relief valve that discharges to atmosphere if something fails. Often required where higher hazard exists.

• Pressure Vacuum Breaker (PVB) and Spill-Resistant Vacuum Breaker (SVB): Common on irrigation systems to protect against backsiphonage.

Our Backflow Testing San Diego experts at Atlas Backflow Services are trained and certified to test all major models and sizes from leading manufacturers.

Step-by-step: what happens during your test

1. Arrival and verification: We locate your assembly and confirm the make, model, size, and serial number against your water provider’s records.

2. Site safety and isolation: We notify you of temporary water interruption if needed, protect nearby equipment, and set up calibrated test equipment.

3. Shutoff and baseline readings: We close shutoff valves in a specific sequence and attach the gauge assembly to the test cocks on the device.

4. Functional checks: We measure differential pressures, observe relief valve opening points, and verify check valve closure and leak tightness per testing standards.

5. Results and documentation: We record pass/fail values, note any deficiencies, and submit the official report to your water authority. You receive a copy for your records.

6. If repairs are needed: We provide a clear quote for repairs or parts replacement and retest after repairs to validate compliance.

Most tests take 20–45 minutes per device when accessible and in good condition. Complex sites or devices behind locked mechanical rooms may take longer.Who needs backflow testing in San Diego?

• Commercial and industrial properties: Required on domestic, irrigation, fire, and process water services.

• Multifamily and mixed-use buildings: Often have multiple assemblies serving different systems.

• Single-family homes: Typically required for dedicated irrigation with PVB/SVB, or where a higher-hazard cross-connection exists.

• Properties with changes: Remodels, new irrigation, added chemical injectors, or new fire systems may trigger new device installation and testing.

San Diego-area requirements Most San Diego water providers and the City’s Cross-Connection Control Program require annual testing by a certified tester, plus test report submission by the due date on your notice.

If you’re unsure, our Backflow Testing San Diego experts can look up your device and confirm your schedule, then handle reporting for you.What causes a device to fail—and how we fix it

• Worn springs and seals: Normal wear reduces closing force and can allow seepage.

• Mineral buildup or debris: Sediment can prevent valves from sealing.

• Corrosion or freeze damage: Exterior exposure and rare cold snaps can crack housings or seats.

• Incorrect installation position or missing clearance: Can affect performance and accessibility.

Atlas Backflow Services stocks common repair kits and parts for popular models, so many repairs are completed the same visit. After repair, we immediately retest to confirm a passing result and submit the updated report.

Benefits of Timely Backflow Testing

• Protects health: Prevents pollutants and contaminants from entering the drinking water system.

• Maintains compliance: Avoids citations, water shutoffs, and fines for overdue or failed tests.

• Reduces liability: Demonstrates due diligence with dated, official test results on file.

• Prevents surprise downtime: Early detection and repair keep your operations or irrigation running smoothly.

How to prepare for your appointment

• Ensure access: Provide keys or codes for mechanical rooms or fenced enclosures.

• Clear the area: Move stored items away from the device and keep pets secured.

• Plan for brief interruptions: Some tests require a short water shutoff.

• Share any notices: Send us your testing notice so we can match serial numbers and due dates.

Answers to common questions

• How often should I test? Most providers require annual testing; some higher-risk assemblies or failed devices may require retesting sooner.

• What does it cost? Pricing depends on device type, size, quantity, and access. We offer transparent, flat-rate testing with volume discounts for multi-device sites.

• Do you file the results? Yes. Our Backflow Testing San Diego experts submit digital reports to your water authority and provide a copy for your records.

• What if my device fails? We’ll explain the issue, provide a clear repair estimate, complete the repair with approved parts, and retest the same visit when possible.

Why choose Atlas Backflow Services

• Certified specialists: Experienced, licensed testers focused exclusively on cross-connection control.

• Local knowledge: We work with San Diego water providers every day and know their reporting systems and timelines.

• Fast turnaround: Reminder scheduling, on-time appointments, same-day reporting, and expedited repairs.

• Customer-first communication: Upfront pricing, photo documentation, and simple next steps.

Our Backflow Testing San Diego experts at Atlas Backflow Services make compliance straightforward, whether you manage a single irrigation PVB or a portfolio of commercial properties with multiple RPZ and DCVA assemblies.Get scheduled today If your notice is due or you want to confirm your status, contact Atlas Backflow Services.

We’ll verify your device information, schedule a convenient appointment, complete accurate testing, and file your report on time.

With our Backflow Testing San Diego experts on your side, you’ll have confidence that your backflow prevention device is doing exactly what it’s designed to do: keeping water flowing in one direction and safeguarding San Diego’s drinking water.