7 backflow prevention devices to recommend to customers.

Backflow prevention devices help ensure that water remains clean. This device is particularly important for drinking water and keeping sewer water and other dirty water out of what your customers use to shower, wash dishes, wash their hands, and other daily tasks.

Before getting into the best backflow prevention devices, here’s a quick refresher on the four main types of these backflow preventers. 

  • Pressure vacuum breakers: Pressure vacuum breakers (PVBs) are the most common of the backflow preventers and the most affordable. They have a body with a single valve that features two test cocks, the outlet shut-off valve, the pressure vacuum breaker, and the check valve, along with the inlet shut-off valve by the bottom. Unless you opt for a spill-resistant version, they can sometimes leak a bit of water.
  • Double-check valves (DCV): These are also known as double-check assemblies (DCA) and work well for indoors and underground applications. In addition to their inlet shut-off valve, they feature two independent check valves: spring-loaded, the outlet shut-off valve, and four test cocks. These devices are the most common in installations that are in-line/below-grade or underground.
  • Reduced pressure zone assembly (RPZ): These are also called reduced pressure principle assemblies and are the most expensive and complicated type of backflow preventer. They are also the most reliable when properly installed. They feature the inlet shut-off valve, a valve for pressure differential relief separating two independent spring-loaded check valves, the outlet shut-off valve, and four test cocks. Some municipalities have restrictions on this type of preventer.
  • Atmospheric vacuum breaker (AVB): These are commonly used in irrigation systems with one or two zones, in which case they are the most affordable and straightforward option. They are not cost-effective with more control valves. However, they are also less reliable than other backflow prevention devices, and most big municipalities do not permit them in sprinkler systems.

We created this list to summarize the best backflow prevention devices that your customers will appreciate. This list can save you the hassle of comparing products to decide which ones to suggest to customers. Keep in mind that your customer’s ideal backflow prevention device will depend on their planned plumbing use.

1. Canplas 223285W Valve With Access Sleeve

Canplas 223285W Valve With Access Sleeve

This Canplas 223285W is a PVC valve that comes with an access sleeve measuring 16 inches with an ABS lid included. This is one of the four-inch backflow prevention devices, but in addition to the valve itself, it features an access sleeve with a lid. That access sleeve makes maintenance a breeze, as you or your customers can use it to remove the flapper valve inside for cleaning.

This particular backflow preventer’s design stops stormwater and sewage from flowing back into the pipes with potable or clean water. Like all the other valves from Canplas, this one features DWV sockets and is set up for socket-to-socket application. It also features an O-ring made of neoprene to seal the lid of the valve securely.

2. Febco 765-1” BV Pressure Vacuum

Febco 765-1” BV Pressure Vacuum 

The Febco 765-1” BV Pressure Vacuum backflow preventer is designed to help prevent the backflow of both toxic and non-toxic liquids. It is highly durable thanks to its bronze construction. It can work with a pressure of up to 150 psi. The single, convenient assembly includes an air opening port and a check valve port. Servicing the unit is very easy, thanks to the ability to access all of the backflow prevention device’s internal parts from its top.

 The system includes one spring-loaded check valve. When the water flowing through the assembly goes to zero, the valve shuts. When the pressure goes down to 1 PSI, the air relief valve will also open, breaking the siphon. There are also two test cocks and two shut-offs.

3. Homewerks Worldwide VACBFPZ4B Vacuum Breaker

Homewerks Worldwide VACBFPZ4B Vacuum Breaker

This Homewerks Worldwide VACBFPZ4B backflow preventer relies on the vacuum breaker design to prevent backflow. It helps your customers avoid contamination of their potable water. Like some of the other backflow prevention devices on this list, this unit installs permanently, as you simply break off a screw upon installation.

 This backflow prevention device can handle temperatures as high as 180 degrees Fahrenheit and pressure of up to 125 psi.  There is a manual drainage feature that is easy to operate and can prevent your customers’ issues that live in areas with cold winters. It is also highly resistant to corrosion thanks to being constructed from brass. Your customers will appreciate the versatility of this backflow preventer, as its standard 3/4-inch hose thread outlet makes it compatible with most systems.

4. Oatey 43904 PVC Backwater Valve

Oatey 43904 PVC Backwater Valve

 The Oatey 43904 PVC Backwater Valve is one of over a dozen backflow prevention devices from the brand with more than 100 years of history serving the plumbing industry. This one is sturdy and works well for preventing backflow in wastewater systems. It has a pipe size of four inches, although the company also has similar valves with different size pipes. It fits standard DWV pipes, and you can quickly adapt it to use this preventer for drain pipes and sewers.

 This backflow prevention device has a threaded access cap with a neoprene seal to ensure sealing while still making the part easy to remove or tighten by hand. The entire unit has a reputation for being extremely durable.

5. Mueller B & K 108-904RP Backflow Preventer

Mueller B & K 108-904RP Backflow Preventer


This Mueller B & K 108-904RP unit uses the vacuum breaker design to prevent backflow. It is an excellent option for your customers who need a backflow prevention device on a budget. It works particularly well for irrigation, including stopping backflow in portable hoses that connect with hose thread faucets. It can also work inside and outside, as long as you have a 3/4-inch hose thread outlet. You can also use the device’s male hose thread outlet to connect it with valves, sill cocks, and hydrants.

The installation for this device is permanent, so encourage your customers to keep that in mind. Of course, since it is so budget-friendly, they will not be out-of-pocket much if they decide to have you remove it in the future. For your customers in colder climates, this backflow preventer features a manual drain release. Remind customers to do this before freezing temperatures hit to avoid damage.

6. Zurn Wilkins 34-975XL2

Zurn Wilkins 34-975XL2 

This Zurn Wilkins 34-975XL2 model is one of the various backflow prevention devices that the brand offers. It is a reduced pressure principle assembly preventer or a reduced pressure zone assembly. It features a short lay length that makes replacing it easier for your team in the future, reducing customers’ costs. The backflow preventer follows a common design that your team has likely worked with many times in the past. This particular device is ideal for irrigation systems like sprinklers.

7. Zurn Wilkins Pressure Vacuum Breaker Assembly 720A

Zurn Wilkins Pressure Vacuum Breaker Assembly 720A

 For those times that you need to suggest a backflow prevention device to help keep sewer water where it should be, this Zurn Wilkins 720A model is a good option. As the name implies, it is a pressure vacuum breaker assembly. The preventer was specifically designed for high-hazard situations, including non-potable irrigation systems. It features a bronze bonnet and body and can handle water up to 110 degrees Fahrenheit and pressure up to 150 PSI.

 The two shut-offs on the unit are very resilient. You will also be able to service it in-line, thanks to the air inlet and check valves. The only thing to keep in mind is that this model can sometimes break down when the temperature drops below freezing.

Conclusion: Why Backflow Prevention Devices Matter

By being aware of the best backflow prevention devices, you are better equipped to make suggestions to your customers. This helps cement your expertise as a master plumber. It also allows you to order the top backflow preventers in bulk so you can have them on hand to install for your customers.

 Your customers may ask for suggestions regarding backflow prevention devices at any step of the process of contacting you. Stay in touch with ease with Podium’s Inbox and Webchat features. You could even use Videochat to show customers what the various recommended backflow preventers look like.

Jennifer Wilson
Jennifer Wilson Strategic Home Services Account Executive

Jennifer Wilson is a home services professional at Podium, the premiere messaging platform that connects local businesses with their customers.

Adapt the way you do business. Press send.