Backflow systems

About our testers

We have been testing, installing, repairing, and replacing backflow prevention devices for over 65 years! Whether you have one device or many, we can take care of them for you. We are certified to service, Los Angeles, San Bernardino and Riverside Counties. Additionally, we carry an ABPA certification which is recognized nationally. Our Backflow testers are ready to service your backflow preventers now!

Contact Us Now (909) 627-2697 or fill out our Backflow test request form:

Please specify what city, county or water company your backflow test forms are from:

What Is a Backflow?

Backflow is the unwanted flow of water in the reverse direction, it can be a serious health risk if there is contamination of potable water supplies with foul water.

In this situation, dirty water from the hillside pool will back-siphon or back-flow down the hosepipe and into the clean water tank. To prevent this from happening, the house’s external tap should be fitted with a backflow prevention device.

Per local, state, and Federal codes, the public water supply must be protected from contamination.

Two types of protection backflow prevention devices are used for meter protection, and internal protection.

A meter protection backflow preventer is located as close to the outlet side of the water meter as possible. Any water that has ran through the water meter is deemed as used and SHALL be allowed to back-flow into the public water system.

An internal backflow prevention device is used to isolate sections in the water system within the building that are supplying equipment, industrial applications, and/or any other condition that could allow contamination into the water system. Water supplies downstream of this type of protection should be clearly marked as non-potable water.

Typically on commercial, a meter protection backflow preventer is required, and if hazards inside the building exist, internal backflows will be required also. Residential applications are at the discretion of the local authorities.

Testing With D&R Plumbing Ensures:

  • Over 65 years of experience to repair & troubleshoot your Backflow Prevention Devices.
  • We keep copies of your test reports for up to 3 years just in case the water or health department needs to see copies!
  • Whether you have over fifty valves or one, we can take care of them for you.
  • We are qualified to test Backflow devices for airlines, schools, apartments, hospitals, medical buildings, mobile home parks, and homeowners, just to name a few of our customers.

Backflow Prevention Devices

A backflow prevention device is used to protect potable water supplies from contamination or pollution due to backflow.

The simplest, most reliable way to provide backflow prevention is to provide an air gap. An air gap is simply an open vertical space between any device that connects to a plumbing system (like a valve or faucet) and any place where contaminated water can collect or pool. A simple air gap has no moving parts, other than flowing water. Many plumbing codes specify a minimum air gap distance required for various circumstances, such as a drain connection for a dishwasher.

Alternatively, a specialized backflow preventer valve may be installed at strategic locations in the plumbing system wherever there is a risk of contaminated fluids entering the water supply pipes. These valves are used where there is not sufficient vertical clearance or physical space to install an air gap, or when pressurized operation or other factors rule out use of an air gap. These valves use moving parts, they are often required to be inspected or tested annually.

Our Backflow Testers service Chino, Ontario, Claremont, Montclair, Rancho Cucamonga, Pomona, Covina, San Dimas, Glendora, La Verne, West Covina, City of Industry, Irwindale, Walnut, Rowland Heights and neighboring areas, portions of Riverside County, Imperial County & Southwest Arizona.