You don’t need to worry if you don’t know the differences between a backflow preventer and a check valve. You aren’t the only one. There are similarities and differences between these two valves. While a backflow preventer prevents fluid from flowing back into the system, the check valve can be opened or shut to prevent fluids from flowing. This isn’t the only difference between these valves. With this guide to knowing the differences, you will never use or purchase the wrong valve again.

The backflow preventer

The backflow preventer. This valve is essential to keep clean water separate from unfiltered water. Something that not many people know is that this valve is also known as an anti-fouling shutoff valve. This isn’t your normal valve; two check valves have a drain valve in the middle.

An example of where a backflow valve is used is in water pipes. The valve prevents polluted water from returning to the drinking water and contaminating the water again. You will find these valves in industrial, commercial, and residential buildings. The reason why people confuse this valve with a check valve is because it has the same function.

The check valve

The check valve differs from the backflow valve, even if they have the same function. The check valve’s main function is to prevent the reverse water flow. There are two types of these valves: the lift and swing valves. With this valve installed, the fluids will only flow in one direction.

This valve uses a swinging or spring-loaded disk that opens, allowing the flow to go forward. Once the valve is closed, it will stop flowing altogether. With the check valves, you will find many sizes that fit household or industrial water systems.

Feature differences between backflow preventer vs check valve

Even with the similarities, there are some differences between the backflow preventer and the check valve. To understand the differences, you need to know these features first.

Backflow preventer

• This valve can be used in residential, industrial, and commercial buildings.
• It can be used for water or gas from backflowing.
• The main function is to keep the contaminated water from flowing back into the freshwater.
• These valves need regular maintenance and can be costly to purchase.

Check valve

• It allows flow in one direction only.
• It can be used automatically or manually, depending on the type of valve.
• This valve has different types and sizes.
• The check valves are relatively cheap and don’t need regular maintenance.

Application of the fittings

This is where the differences between the backflow preventer and check valve occur. The main application of the backflow preventer is to keep fresh water from being contaminated with sewerage water or unfiltered water again. It offers double the protection with two check valves.

The check valve’s application is to stop fluid from flowing through the opposite direction. It is normally used in Aquaiums, plumbing systems, sump pumps, and gas pipelines. The valve only has one layer of protection; it has a valve disc that can close or open.

Advantages and disadvantages differences;

Another great way to understand the differences between a backflow preventer and a check valve is to know more about the advantages and disadvantages of each valve. It also gives insight into which valve will be better for which installation.

Backflow preventer advantages

• With this valve, the water will stay clean and safe to use. This can keep filtered water away from the unfiltered water.
• The spillage and sewerage smell will be minimized with the backflow valve.
• Complying with the legal codes and regulations for water installations will be easier.
• The disruption caused by backflow events will be eliminated.

Disadvantages

• Installing the backflow preventer valve can be messy. The cleaning and maintenance of the valve will also be messy.
• Installation of this valve will be expensive.
• Access to the exact location where the valve must be installed or replaced can be hard.
• No one can install the valve. It isn’t easy and needs an experienced plumber.

• Backflow of water or gas will be prevented in households and commercial buildings.
• It can withstand high and low temperatures without causing damage to the valve.
• Installing the check valve will be faster and easier. And it doesn’t require an experienced plumber to install.
• The valve is relatively cheap to purchase.

Disadvantages

• Check valves can fail. This causes a loss of control over the flow of fluids throughout the plumbing system.
• These valves can get clogged easily, causing downtime. It can’t always be repaired and needs replacements.
• Loss of pressure in water or gas is possible and can cause frustration.
• Normal wear and tear will occur over time, and replacements will be needed.

Different varieties of these fittings

There are also some differences between the backflow preventer and the check valve, including the number of different types of valves you can find. There are several different preventer types to choose from with the backflow preventer fittings. These are the different types of backflow fittings:

• Pressure vacuum breaker
• Atmospheric vacuum breaker
• Double-check valve assembly
• Reduced pressure zone assembly.

There are also a couple of different check valves to choose from. These include the:

• Piston check valve
• Ball check valve
• Stop check valve

The main differences in short

These are the main differences between the backflow preventer and the check valve. It is to make sure that you know exactly what the main differences are:

Main function

The backflow preventer prevents contaminated water from flowing into fresh, clean water. The check valve stops fluids and gas from returning to the opposite direction. The check valve can be used in households and isn’t hard to install.

Protection

With the backflow fitting, it has double the protection. This is due to the two layers of protection. This protection is known as two check valves. The check valve only has one layer of protection. This is enough protection to prevent gas and water from flowing backward.

Location and installation

The backflow fitting is installed in homes where the sewerage and fresh water can overlap and where the sewerage can run back to the freshwater. Installation is complicated and expensive, and only an experienced plumber can replace them. The check valve can be found all over the homes. Check valves are needed in low-hazard situations and where only one layer of protection is required.

Backflow preventer vs check valve. Knowing which fitting to use

Knowing the differences between the preventer and check valve isn’t enough to prevent purchasing the wrong fitting. You also need to know when you should install which fitting. These are some things to remember when deciding which valve to purchase.

• Know the main reason why you want to install the fitting. Is it to ensure flow in the right direction, or do you want to prevent backflow?
• Access to the system. If you need to disrupt the environment to get to the pipeline, then you need to install a backflow preventer. And you will need to hire a plumber. Check valves will be required for indoor use and small water systems where access to the pipes is easy.

If you are unsure which fitting to purchase, talking to an experienced plumber will be helpful.

FAQ about backflow preventers and check valves

You might find the answers with these FAQs for those still wondering if backflow preventers and check valves are needed.

Does a backflow preventer cause low water pressure?

Yes, it can cause low water pressure, especially if the preventer needs replacement or maintenance. Other aspects can cause the backflow fitting to reduce water pressure.

Can I repair my check valve?

There are some circumstances where you can repair a check valve, but in most cases, it is recommended to replace the valve instead. One thing you can do is to take the valve apart and look for debris and scratches that can cause failure.

How do you know your check valve has failed?

There are a couple of signs that your check valve is failing. It is leakage, pressure loss, contamination, and complete system failure.

Conclusion

Backflow preventers and check valves. Is there a difference between when you should install the check valve and when a backflow preventer is necessary?

With this discussion about the differences between a backflow preventer and a check valve, you will understand the differences more easily. It will become clear when you should install which fitting. It is always best to seek professional assistance at any recommended plumbing store if unsure.