Backflow Preventers vs Check Valves: What Is The Difference?

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    Backflow preventers and check valves are similar pieces of plumbing equipment that seem to do the same thing – but there are actually a few key differences! In this article we will compare backflow preventers vs check valves to see which is the right option for your project.

    Keep reading to find out the pros and cons of each system as well as the best backflow preventers and check valves – plus how to pick the right type of valve!

    Backflow Preventer or Check Valve?

    Backflow preventers and check valves serve a similar purpose – any may seem like the same thing – but there are a few key differences to know about before installing a new valve. Both kinds of valves have the same end goal – to prevent backflow in a pipe and keep water moving in one direction.

    Litorange Backflow ConnectorPrevents dangerous backflow from entering water pipesSee Price
    Campbell Check ValvePrevent backflow from entering drainage linesSee Price

    If you are looking to install a valve on a water supply we recommend choosing a backflow preventer instead of a check valve. They are more dependable and less likely to fail and contaminate your water supply thanks to their fail safe design. The price may be higher but the cost is worth protecting your drinking water.

    If you are looking to install a one way valve on a sump pump line or other non potable water line we recommend choosing a check valve. Check valves cost considerably less than a backflow preventer but have a slightly higher failure rate due to the moving parts failing and seals leaking!

    Trying to Decide – Don’t Be Cheap On Drinking Water

    If your valve will be installed on a water line used for drinking water (or an outdoor shower) it is important to protect your water supply with a backflow valve! They may cost a little more but are guarantee clean water!

    Backflow Preventer Advantages

    Backflow preventer’s biggest advantage is the ability to keep your drinking water clean. They most cost more than a similar-sized check valve but they provide 100%, long term protection for your drinking water.

    Recommended Backflow Preventer

    Wilkins Backflow Preventer

    Our pick for the top backflow preventer is the Wilkins Reduced Pressure Backflow Preventer. It is lead free and designed for use on drinking lines!

    What is a Reduced Pressure Zone (RPZ) backflow preventer

    A reduced pressure zone is a type of backflow prevention device that consists of two check valves plus an an intermediate relief valve. RPZ valves are the most dependable type of backflow preventer because if they fail they water will drain out of the valve instead of back into the water supply.

    Check Valve Advantages

    The biggest advantage check valves have over backflow preventers is cost. Since these valves are protecting your water source they need to be much more dependable and robust – allowing backflow can be a serious health risk!

    Check valves on the other hand cost less but will eventually have some back flow as the swing valve and seals breakdown.

    What is a Double Check Valve

    Double check valves (also called a double check assembly) is the middle ground between a check valve and backflow preventer. They are normally installed in areas where backflow needs to be prevented with a one way valve, but the investment needs to be smaller than a backflow preventer.

    Recommended Check Valve

    Zoeller Check Valve

    We recommend the Zoeller 30-0181! It is affordable on any budget is made with super high-quality plastic which is unlikely to break or leak!

    Related Posts About Check Valves

    How To Pick The Right Valve

    Still not sure if you need a check valve or backflow preventer? Since these valves are so similar we put together a series of 5 questions to ask yourself before making a final decision.

    • Level of protection – The first thing to decide is the level of backflow protection you need. Drinking lines for potable water need a higher level of protection than your basement sump pump check valve. Some homeowners insurance policies will require either a check valve or backflow preventer in order to cover water damage – be sure to check with your agent and policy!
    • Total cost – The second thing to consider when choosing between a check valve and backflow preventer is your budget. A good check valve costs less than $100 and should last for at least 5 years without failing. Backflow preventers, on the other hand, cost at least a few hundred dollars which means it is more investment for households on a budget.
    • Lifespan – Backflow preventers have a longer working lifespan than check valves. After a few years, it is not uncommon to see check valve seals and swing valves start to fail and allow some backflow. If you are renting, planning on moving, and not protecting drinking water we recommend choosing a check valve instead of a backflow preventer.

    Frequently Asked Questions

    Is a double check valve the same as a backflow preventer?

    Double check valves are similar to backflow preventers but they are not the same thing! Double check valves provide more protection than a single check valve but still can have some backflow.

    Can a check valve be used as a backflow preventer?

    A check valve can be used as a basic backflow preventer in emergency situations but should not be used to protect drinking water long term.

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