If you’ve had to deal with wastewater siphoning back into your washing machine or water flowing out of your washer during a rinse cycle, you probably know the painful feeling.
Whether you have experienced this in your washer before or not, it is a problem that is caused by a component called a check valve.
A washing machine check valve is a component that is used to prevent water from flowing back into the washing machine tub after the pump has removed the water from the tub.
This is important because it helps to prevent water from entering the pump and causing damage to the machine.
Another reason that a check valve is important is that it helps to prevent water from being siphoned out of the washing machine during the rinse cycle.
You don’t want to learn the hard way that this is an important function, as not having a functioning check valve can cause water to enter the pump and damage the machine.
In this article, we will explain the nitty gritty of washing machine check valves, their pros and cons, and essential information you need to know about them.
Table of Contents
What is a washing machine check valve?
A washing machine check valve is a small, but important component found in most modern washing machines that prevent the backflow of water or wastewater in the washing machine’s drainage system.
There are check waves that are used inside the drain pump of a washing machine to prevent the backflow of wastewater that is ejected through the pump drain.
Also, there are check valves that are connected at the end of the hot and cold water supply hoses that connect to the back of the machine.
These hoses are under pressure when the washing machine is in use, and the check valve helps to prevent water from flowing back into the hoses and potentially causing damage.
How washing machine check valves work
Washing machine check valves are designed to prevent water from flowing back into the washing machine when it is not in use.
They are typically located near the water inlet hose or the water pump, and they consist of a spring-loaded valve that is held closed by a small ball bearing.
When water is flowing into the washing machine, the pressure forces the ball bearing against the spring, causing the valve to open.
This allows water to flow into the machine and start the wash cycle.
When the wash cycle is complete and the water is no longer flowing, the pressure drops and the spring pushes the ball bearing back into place, closing the valve.
When your washing machine is not in use, the water in the drain hose may be at a higher level than the water in the machine itself.
This can create a siphon effect, where the water in the hose is drawn back into the machine due to the difference in pressure.
To prevent this from happening, washing machine check valves are installed in the drain pump inside the washer.
These valves are designed to allow water to flow out of the machine and into the drain, but they prevent water from flowing back into the machine.
It’s important to note that check valves are not the only mechanism that washing machines use to prevent wastewater from siphoning back into the machine.
Some machines also use air gaps or standpipes to prevent this from happening.
Types of washing machine check valves
There are several different types of check valves that can be used in a washing machine, and each has its own unique features and benefits.
Here is a detailed look at the different types of washing machine check valves:
Flapper-style check valve: This is the most common type of check valve found in washing machines. It consists of a rubber flapper that is attached to a spring-loaded arm. When water flows through the valve, the flapper opens to allow the water to pass through. When the water flow stops, the flapper closes, preventing water from flowing back into the drain pump.
Swing-style check valve: This type of check valve uses a swinging arm to block the flow of water. When water flows through the valve, the arm swings out of the way to allow the water to pass through. When the water flow stops, the arm swings back into place, blocking the flow of water.
Ball-style check valve: This type of check valve uses a ball that is seated in a cage to block the flow of water. When water flows through the valve, the ball is lifted off its seat, allowing the water to pass through. When the water flow stops, the ball falls back into place, blocking the flow of water.
Diaphragm-style check valve: This type of check valve uses a flexible diaphragm to block the flow of water. When water flows through the valve, the diaphragm is pushed out of the way, allowing the water to pass through. When the water flow stops, the diaphragm returns to its original position, blocking the flow of water.
It is worth noting that the most common type of washing machine check valve that is used for washers is the flapper-style check valve.
This type of check valve consists of a rubber flapper that is attached to a spring-loaded arm. When water flows through the valve, the flapper opens to allow the water to pass through.
When the water flow stops, the flapper closes, preventing water from flowing back into the drain pump.
The flapper-style check valve is a simple and effective design that has been used in washing machines for many years.
It is easy to install and maintain, and it is capable of handling a wide range of water flow rates.
As a result, it is the most widely used type of check valve in washing machines.
Pros and Cons of washing machine check valve
We believe by now you agree to the fact that washing machine check valves are an important accessory in a washing machine.
However, let’s go deeper and discuss the pros and cons that washer check valves come with.
Pros of washer check valve
1. Prevents water damage: As mentioned, the primary benefit of a check valve is that it helps to prevent water from flowing back into the washing machine or other plumbing fixtures, which could cause water damage.
2. Easy to install: Check valves are relatively easy to install and do not require any special tools or skills.
3. Inexpensive: Check valves are generally inexpensive and can be easily purchased at a local hardware store or online.
4. Can help to extend the life of the washing machine: By preventing water from flowing back into the washing machine, a check valve can help to extend the life of the machine by protecting it from potential water damage.
5. May be required by local building codes: In some areas, local building codes may require the installation of a check valve in the water supply line to a washing machine.
Cons of washing machine check valve
1. Can become clogged: Over time, check valves can become clogged with dirt, debris, or other contaminants, which can reduce their effectiveness or cause them to fail completely.
2. May cause pressure issues: If a check valve is not properly installed or if it becomes clogged, it can cause pressure issues in the water supply line, which can lead to problems with the washing machine or other plumbing fixtures.
3. Possible water flow issues: In some cases, a check valve may restrict the flow of water to the washing machine, which can lead to problems with the machine’s performance.
4. May require regular maintenance: Depending on the type of check valve and the quality of the water supply, it may be necessary to perform regular maintenance on the valve to keep it functioning properly. This could include cleaning or replacing the valve if it becomes clogged or damaged.
5. May not be necessary in all cases: In some cases, a check valve may not be necessary, depending on the quality of the water supply and the risk of backflow. It is important to carefully consider the need for a check valve before installing one to ensure that it is the best solution for your specific situation.
Do you need a washing check valve for your washing machine?
As mentioned earlier, most washers come with a check valve already connected to the drain pump that prevents the backflow of wastewater into your tub or drum.
The main consideration would be whether you need a check valve for your water supply or not which will depend on a few factors.
It is also possible to install a separate check valve in the water supply line to the washing machine.
These are a few things to consider about installing a check valve on your water supply:
Quality of the water supply: If you have a high-quality water supply that is not prone to sudden drops in pressure or backflow, you may not need a check valve.
Risk of water damage: If you are concerned about the risk of water damage to your washing machine or other plumbing fixtures, a check valve may be a good idea.
Local building codes: In some areas, local building codes may require the installation of a check valve in the water supply line to a washing machine.
How to install a washing machine check valve
Installing a washing machine check valve is a relatively simple process that can be done by most homeowners with basic plumbing skills.
Here is a step-by-step guide on how to install a washing machine check valve:
- Pipe wrench
- Adjustable pliers
- Pipe cutter
- Teflon tape
- The check valve itself.
- Locate the water supply line: The first step is to locate the water supply line that leads to your washing machine which is typically a flexible hose that connects the washing machine to a water supply valve or a pipe in the wall.
- Shut off the water supply: Before you begin any work on the water supply line, it is important to shut off the water supply to the washing machine. This can usually be done by turning off the valve that controls the water supply to the machine.
- Cut the water supply line: Using the pipe cutter, carefully cut the water supply line at a point that is convenient for installing the check valve. Be sure to leave enough slack in the line to allow for the movement of the washing machine.
- Install the check valve: Depending on the type of check valve you are using, installation may vary slightly. However, most check valves are installed by attaching one end of the valve to the water supply line and the other end to the washing machine. Some check valves may also require the use of Teflon tape to ensure a secure seal.
- Test the check valve: Once the check valve is installed, turn the water supply back on and test the valve to ensure that it is functioning properly. If you notice any leaks or other problems, shut off the water supply and make the necessary adjustments.
- Secure the check valve: Once the check valve is working properly, use the pipe wrench and adjustable pliers to secure the valve in place. Be sure to tighten all connections firmly to prevent leaks.
How to replace a washing machine drain pump check valve
It may be that the check valve on the drain pump may have worn out and cousing drainage and siphoning problems. It’s possible to replace the valve and you can watch the video below to guide you through the procedure.
Symptoms of a faulty washer check valve
A faulty check valve in a washing machine can cause a variety of problems, some of which can be serious.
It’s important to be aware of the symptoms of a faulty check valve so that you can address the issue before it becomes a major problem.
Here are some of the most common symptoms of a faulty check valve in a washing machine:
1. Water leaks: One of the most obvious signs of a faulty check valve is water leaks. If you notice water leaking from the washing machine, it could be due to a faulty check valve.
2. Slow or incomplete drainage: If your washing machine is not draining as quickly or completely as it should, it could be due to a faulty check valve.
3. Loud noises during the drain cycle: If you hear loud noises coming from your washing machine during the drain cycle, it could be due to a faulty check valve.
4. Vibrations during the spin cycle: If your washing machine is vibrating excessively during the spin cycle, it could be due to a faulty check valve.
5. Clogged drain hose: A clogged drain hose can also be a symptom of a faulty check valve. If you notice that your drain hose is clogged, it could be due to a faulty check valve.
6. Waste water inside your tub or drum after draining: If you notice that wate water is left sitting inside your drum a whileafter you completely drained the washer, it could be that the check valve isn’t functioning properly.
If you have determined that your check valve is faulty, there are a few options for fixing it.
Here are some tips and tricks for fixing a faulty check valve:
1. Replace the check valve: If the check valve is damaged or worn out, the best option is to replace it with a new one. This is a relatively simple process that can usually be done by a professional, or you may be able to do it yourself if you are comfortable with home repairs.
2. Clean the check valve: If the check valve is clogged or dirty, you may be able to clean it and get it working properly again. To clean the check valve, you can use a small brush or a pipe cleaner to gently scrub away any dirt or debris.
3. Check for other issues: If the check valve appears to be in good working order, it’s worth checking for other potential issues that could be causing the problem. For example, a clogged drain hose or a malfunctioning pump could also cause problems with the drain cycle.
How do I prevent backflow on my washing machine?
One of the primary ways to prevent backflow on a washing machine is to maintain the check valve. By regularly checking and cleaning (or replacing) the check valve, you can help to ensure that it is functioning properly and preventing backflow.
Other steps you can take to prevent backflow on your washing machine include:
Proper installation: Make sure that the washing machine is installed correctly and that the drain hose is properly connected and secure.
Use a standpipe: A standpipe is a pipe that is installed in the floor near the washing machine and is used to direct the drain hose. It can help to prevent backflow by providing a proper outlet for the drain hose.
Check the drain system: If the drain system is clogged or not functioning properly, it can cause backflow in the washing machine. Make sure to regularly clean and maintain the drain system to help prevent this issue.
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