Backflow Prevention Services

For back-flow testing and installation services in Vancouver and throughout the GVRD nobody has you covered like Mainland Plumbing. We handle back-flow and cross-connection services for many of Vancouver’s most successful companies and property owners including restaurants, construction companies, property management firms and home owners. We handle every size of back-flow prevention project. No job is too big or too small.

MPH handles every aspect of your back-flow prevention requirements. From supplying valuable knowledge about back-flow products, installation, repair services and annual testing and inspections we are a one stop shop! In our 20 years of experience we have become Vancouver’s trusted name in back-flow testing and installation.

What is Back-flow in a Plumbing System?

Backflow in a plumbing system can create a serious and costly problem. It occurs when the flow of water in your plumbing system reverses. This usually occurs because of changes in pressure. These pressure changes can be caused deep inside the plumbing system or even within the structure.

What Problems Can Backflow Create?

Backflow issues are serious because it can contaminate clean water in your plumbing system (drinking water). That can lead to all kinds of health issues and possible lawsuits. MPH can install devices to help prevent this backflow problem from ever affecting your home or business.

Types of Backflow Prevention Products

Their are several backflow prevention products that we recommend based on the size and type of plumbing system. The backflow prevention systems we encounter most commonly are pressure vacuum breakers (PVB), reduced pressure zones (RPZ), double check assemblies (DCA) and atmospheric vacuum breakers (AVB).

Choosing the correct backflow prevention method is very important and requires a through understanding of the subject. Many factors that must be taken into consideration when selecting a backflow prevention device. The size of the plumbing system, usage, building codes and the location of where the backflow preventer is to be installed are the most important considerations. MPH can help determine the best backflow device for your application.

Pressure Vacuum Breaker

Pressure vacuum breaker assemblies (PVB) are very common. These are the most economical type of backflow preventer and their simple design allows for easy maintenance and installation. They are ideal for most applications and the system we tend to see most commonly. The PVB device consists of an inlet shutoff valve at the bottom, a single valve body consisting of a pressure vacuum breaker, check valve, two test cocks, and an outlet shutoff valve.

MPH has experience working with almost every brand of PVB backflow device. We can repair, install and recommend the perfect pressure vacuum breaker for your home or business needs.

Double Check Valves

Double check valves (DCV) are sometimes referred to as double check assemblies (DCA). These are ideal backflow devices for underground and indoor installations. A DCV / DCA consists of an inlet shutoff valve, two independently operating spring-loaded check valves, four test cocks and an outlet shutoff valve. Double check assemblies should only be installed vertically if allowed by local building codes.

Double Check Valve Assembly

The DCA is a common type of backflow prevention device used in underground or in-line installations. In-line (or below-grade) means that the backflow device is parallel with the piping of the sprinkler system. Unlike the PVB, the DCA does not have to be installed 12 inches above the highest point in the system. Some areas do require above-ground installation, so check with local authorities before installing below ground.

Over our 20 years in business we have worked with almost every brand of double check valve and assembly device. We have installed, repaired and provided maintenance services for these systems and products throughout Metro Vancouver. If you need help with product selection or installation services give us a call. No job is too big or too small.

Reduced Pressure Zone Assembly

Reduced pressure zone assemblies (RPZ) are the most complex and expensive backflow preventer. They are sometimes referred to as “reduced pressure principle assemblies”. The RPZ is the most secure and reliable of all the backflow prevention devices. It is our recommended choice of backflow prevention system for most of our large commercial and industrial clients. The RPZ consists of an inlet shutoff valve, two independently operating spring-loaded check valves separated by a pressure differential relief valve, four test cocks and an outlet shutoff valve.

Local building codes are very strict about the type of RPZ system used and how it is installed. A thorough understanding of RPZ systems and local building codes are required before proceeding with this kind of backflow prevention device. MPH can help you understand Vancouver’s RPZ requirements and the best products for your application.

Atmospheric Vacuum Breakers

Atmospheric vacuum breakers (AVB) are a simple, efficient and cost effective solution for one or two-zone irrigation systems. An AVB must be installed on the pipe directly after every control valve. AVB devices are therefore not recommended for systems with many control valves.

AVBs are also the least reliable and least often recommended. Most large cities and suburbs do not allow the use of atmospheric vacuum breakers in lawn sprinkler systems. AVBs cannot be used where they would be subjected to constant pressure, where shutoff valves would be located downstream, where there is a potential for backpressure, or on any system that incorporates chemigation techniques.