Washing Machine Check Valve For Backflow Prevention.

Nothing is more grievous than a wastewater backflow, and that’s why protecting your drain system from the washing machine’s wastewater is essential. One way to do that is by fitting a washing machine check valve.

With it, you prevent the back movement of wastewater into the drainage system, thus protecting your laundry from spoiling. It also protects your washer’s tank from damage and saves you from increased energy consumption, among other benefits. 

This washer’s device is essential when your washer and the sewer are not correctly connected. However, the valve does not stop the wastewater from leaving the washer’s tank if it manages to escape.

The obvious question is, is the check value valve worth it? Should you install it?

We’ll look at the pros and cons of the valve, how you can install it, and the types that exist. But before that, let me explain what a check valve is and how it works. 

what is a washing machine check valve

What Is a Washing Machine Check Valve?

A check valve is a safety device that allows a one-direction flow of the gasses and fluids. Thus, its goal is to prevent backflow, and it is often known as an anti-siphon or non-return valve. Other manufacturers call it the clack, one-way reflux, or retention valve. 

The valve creates a tight seal that prevents leaks and not just backflow. Once the check valve shuts, wastewater can’t go back, forming a water hammer.

How Does a Check Valve Work?

The check valve’s working mechanism is pretty straightforward. This non-return valve fits onto the sewer pipe, drain pipe, or siphon to create a barrier against wastewater backflow.

The valve allows wastewater from the washing machine to enter and drain into your home sewer during its operation.

And in case of backpressure, the valve stops the water from going back to the draining by shutting off completely. The valve is effective at doing that because it creates a spring (rubber membrane) damper that completely seals the drain system, protecting it from dirty water.

Some check valves have a rubber ball instead of a rubber membrane that acts as a gate against backflow. The ball only allows wastewater from the drain to go to the sewer but not the reverse.

Should I Fit a Washing Machine Check Valve?

After knowing what a check valve is and how it works, the obvious question is, do you really need it? To answer that, let’s look at the pros and cons of the valve.

Pros of Check Valve

Generally, fitting a check valve comes with these advantages:

  • Backflow Prevention – The valve blocks waste flow from going back into your drainage system and causing havoc.
  • Pump and Compressor Protection – The valve protects your pump from damage by preventing backflow. In the same manner, it protects the compressor from damage.
  • Safety Enhancement – The valve stops wastewater from going back to the drainage system and being in circulation. In doing so, it boosts wastewater usage safety.
  • Clean Laundry – Since the valve stops wastewater from going back to the washer’s tank, it ensures you’ve clean water for your laundry.
  • Averts Water Hammer – A water hammer is when the water pressure surges and shuts down the valve, stopping the flow of fluids and glasses.

In most cases, it leads to damage to the drain system and costly repairs. Note that not all check valves avert water hammers but only those with a quick closing process.

do i need a check valve on a washing machine

Cons of Check Valve

Now, here are the concerns that come with installing a check valve:

  • Water Hammer – Unless you use a quick-closing check valve, your drain system may face a water hammer whose consequences are expensive to fix.
  • Reverse Flow – If you install the check valve incorrectly or get the size wrong, there’s always the danger of allowing the reverse flow of wastewater. So, it’s crucial to pick the right non-return valve size and fit it correctly or hire an expert.
  • Limited to Enclosed System – Sadly, you can only use a check valve in an enclosed system. You cannot use it in an open system.
  • Impossible to Inspect – Once fitted, it’s impossible to inspect their condition. You cannot tell if they are closed or open, or broken.

Now, Do I Need a Check Valve On a Washing Machine?

There is no denying that check valves have a few concerns. Yes, these valves may result in a water hammer, but only when you fit options with a slow shut mechanism.

It’s also true that these valves can result in a reverse flow, but that’s if you get the sizing or the installation wrong.

Overall, you can do nothing about their inability to allow inspection and being restricted to an enclosed system.

But on a positive note, the fact that they prevent wastewater backflow, protect your pump and tank and avert water hammer makes them worth it.

So, if these are the goals you would want to achieve, then, yes, you need a check valve on a washing machine.

Now, here are some of the best washing machine check valves on Amazon:

  • Samsung D662-00299A Valve Check – Best for Samsung Washer
  • Samsung DC62-00202A Valve Check – Alternative Pick for Samsung Models
  • LG ABQ73502701 Check Valve – Best for LG Washers
  • Xavax Non-Return Valve – Best for Washers with an Inner Diameter of Less Than 10mm
can i use a check valve for washing machine drain

Types of Check Valves for Washing Machine

Though there are many types of check valves, here are the most typical choices:

a) Swing Check Valves

Swing check valves are self-actuated non-return valves with a hinge attached swing disc that swings back to its position to prevent reverse flow.

It’s crucial, however, that the disc is thick and robust enough to withstand the heavy impact of the reversing flow.

Overall, swing check valves are ideal in situations where the likelihood of experiencing a water hammer is high.

b) Tilting Check Valves

As the name suggests, tilting check valves have a tilting disc instead of a swinging option. In that case, they tilt to allow fluid to flow through them.

But once the fluid passes, it can’t go back as the disc tilts back to regain its position and closes completely. However, tilt check valves are not as thick and strong as swing check valves.

c) Folding Disc (Double Disc, Dual, Split Disc, or Butterfly) Check Valves

Folding disc check valves, which go by all the other names listed above, open into half at the centerline when the fluid moves forward.

But when the fluid reverses, the valve halves to seal the pipe, preventing backflow. They operate the same way as a butterfly’s wings, thus the name butterfly check valve.

d) Ball Check Valves

As the name hints, Ball check valves feature a ball-like gate that opens to allow forward flow and completely black the pipe passage to prevent backflow.

The ball rides typically on the high pressure of the flow, and once the pressure reduces, it goes back into its position and sits there tightly to prevent backflow.

e) Diaphragm Check Valve

Diaphragm check valves have a c-shaped disc that sits in the drainpipe to open when the wastewater flows forward and shut completely to prevent backflow.

f) Air Check Valves (Pneumatic Check Valve)

Air check valves, also known as pneumatic check valves, let in air, forming a seal that prevents backflow. They are generally best for circuits or systems which only require one-direction airflow.

g) Silent Check Valves (Poppet Check Valves) 

Silent check valves operate by closing so fast immediately after fluid passes through to prevent flow reversal. As a result, they are the most effective against water hammers.

How Do You Install a Check Valve On a Washing Machine?

Though check valves come in different types, they have the same installation process for washing machines.

But before we can look at the installation steps, let’s highlight the requirements.

Must-Have Requirements

  • Check valve
  • Pipe cutter (to cut the pipe to size)
  • Flexible hose
  • Silicone sealant
how do you install a check valve on a washing machine

The Steps 

Step 1: Disable The Washer – Start by disconnecting your washer from the main

Step 2: Sewer Inspection – Examine your sewer system for leaks and obstruction and act accordingly.

Step 3: Check Valve Interconnection – The check valve has two ends with varying diameters. So, connect one end to the sewage pipe and the other to the washer’s drain hose

Step 4: Seal Up – Now, take the silicone sealant to seal the joints ends

That’s it! Those are the four steps for installing a check valve on a washing machine, and you can count on it to stop backflow.

People Also Ask

1. Can I Use a Check Valve for Washing Machine Drain?

Though it’s not a must, you can use a check valve on a washing machine drain to prevent wastewater backflow and protect the washer’s tank from polluted water.

In doing so, you can enjoy clean laundry water and protect your washer pump.

2. What Does a Washing Machine Check Valve Do?

A washing machine check valve seals the drainpipe or hose once wastewater passes through it to prevent backflow. As a result, it protects your washer tank and drains system from reversed wastewater.

3. What Is the Difference Between Check Valve and A Non-Return Valve?

There is no difference between a check valve and a non-return valve as both work by promoting one-direction fluid flow and preventing backflow. It explains why the two names are often used interchangeably.

4. Does A Washing Machine Need a Double Check Valve?

Most domestic washing machines have inbuilt backflow preventers, which eliminates the need for double-check valves.

The exceptions are 3-category fluids: sodium hypochlorite (bleach), ethylene glycol, and common disinfectant, which require double check valves.

5. Where Should a Check Valve Be Installed?

A check valve should be installed on the pump’s outlet or in front of the control valve for easy maintenance. But when it comes to washing machines, you can install them in the drainpipe, sewer pipe, or siphon.

6. Can You Clean a Check Valve?

While it’s not possible to inspect check valves when installed, you can unscrew them and rinse them to get rid of debris. So, yes, you can clean a check valve.

7. How Do I Stop My Washing Machine from Back Flowing?

You can stop your washing machine from back flowing by installing a check valve. It’ll open during the forward flow of waste and shut automatically to prevent backflow.

Closing Thought

Above is everything you should know about the washing machine check valve. This check valve is an excellent addition to your washing machine if you want to protect it from the damaging effects of wastewater backflow.

So, while it suffers a few downsides, its benefits are tremendous, which matters.

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