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Sump Pump Check Valve (What Is It and How Does It Work?)

Sump pump check valves can prevent a lot of problems. A sump pump check valve ensures that a pump works the way it should instead of malfunctioning and causing problems that it was meant to solve.

Inspection check valve on closed drain sump pump.

If you already own a sump pump, chances are good that you are well aware of the advantages of such a piece of equipment. It’s also an easy bet that you haven’t had any flooding problems lately either. If, on the other hand, you have not invested in a sump pump, you probably will after you read of the distinct advantages of having one. Regardless of where you are on this continuum, this article will provide you with just a little extra information about the inner workings of a sump pump and what an amazing tool it can be, especially when it comes to preventing a lot of very serious and expensive flooding problems in your home.

A sump pump is situated in an opening in your floor called a sump pump pit, which is located at the lowest possible place in a home or office, whether it be in a basement, a crawlspace, or any other strategically located area. The actual location of the pit is unimportant, but what is important is that it be wherever flood water stands the greatest chance of accumulating after it enters your home.

Related: Types of Sump Pumps | Types of Heat Pumps | How Sump Pump Works in Basement | Should There be Water in my Sump Pump Pit | How Often Should Sump Pump RunSubmersible Sump Pump vs. Pedestal Pump | How Sump Pump Works in Crawl Space

How Does a Sump Pump Check Valve Work?

PM and Inspection check valve on closed drain sump pump process.

By now you are probably well aware of what a sump pump is and how it can help you to prevent a lot of problems. One of the most important parts of a sump pump is the check valve, but in order to better understand what that part does it is important that you know something about how it works in the grand scheme of things.

In its most basic form, a sump pump is a mechanical device that checks flooding in a home or other structure to keep it from doing damage. Flooding, obviously, can come from nearly anywhere, from your own home to practically anything outside, manmade or not. Wherever that flooding water comes from, what matters most is where it is going, which is what the sump pump helps with.

As far as mechanical devices go, a sump pump is a simple, but a very well-made piece of equipment. Its job is simply to move water from the sump pit to the outside of your home or other structure. You might, for example, have your sump pump direct water to a septic system or an outdoor drainage system. Regardless, your sump pump moves water from where it is to where you want it. It does that with a device known as a check valve. The check valve ensures that the water is directed to the outside continues to flow that way instead of getting turned around.

Inside of a sump pump, there is a propeller that makes sure that water goes in one direction only. You could call a check valve a back up to make sure that this works correctly instead of having water run in a different direction. If your sump does that, water will end up in your home and not outside where you want it. Instead, your check valve ensures that the water that is flowing through your sump pump is flowing in the right direction.

Sump Pump Check Valve Vertical or Horizontal

Raybend,"Silent" Sump Pump Check Valve, 1-1/2"

Despite the fact that sump pumps operate to provide the same purpose, they are often designed very differently. Not only that, but the check valves of a sump pump might be very different from one model to another. One of these differences is whether the check valve is in a vertical or horizontal position to the pump. Personal preferences aside, most experts agree that there is little real difference between check valves and whether they are oriented in a vertical or horizontal position. It is also important to know that there are some municipalities that have their own requirements as to whether a sump pump check valve is oriented horizontally or vertically.

Zoeller 30-0238 Inline Check Valve, Small, Black

You need to check with these authorities to make sure you are in compliance. You should also try to make sure that a check valve is made to operate with the sump pump you have. Just as is the case with many appliances, brands will often be made with parts that are made to be used with their equipment and no other. Unfortunately, sometimes off-brands made parts for these appliances. Sometimes they work, but sometimes they don’t. You might try to save some money, but you might be very disappointed. On the other hand, substitutions work with very little effect.

What professionals do agree on, however, is that a sump pump should be checked periodically to make sure that the check valve is working in the correct manner. Unfortunately, this takes a little more effort than putting your hand on it to make sure it’s running. It could be running and making vibrations, but if it is not operating in the correct direction, you need to take action in order for it to work correctly.

Do You Need a Check Valve on a Sump Pump?

PM and Inspection check valve on closed drain sump pump process: check valve.

Asking whether you need a check valve in a sump pump is like asking if you need seatbelts in a car. The answer to both questions is, no, but it sure helps if they are there. In the case of a sump pump, most designs have a check valve with them, and that’s a good thing. Inside every sump pump, there is a propeller that keeps water moving in the direction it is intended to.

Unfortunately, sometimes things go wonky and that propeller can change directions, or stop working completely. The result is, well, a mess. When this happens you could feel the pump, but even the vibration of the pump won’t tell you that the water is moving in the wrong direction. Instead, it requires taking the pump apart to ensure that the water is moving in the right direction. The alternative to all this hassle is a check valve, which will make sure that the water is moving correctly.

If you have a check valve, and it is operating correctly, chances are very good that your sump pump will work correctly. A check valve is one of those things where it’s better to have one and not need it than to need one and note to have it. In some cases, however, municipal authorities require that you have a check valve on any sump pump. Better to be safe than sorry.

How Long Does a Sump Pump Check Valve Last

Superior Pump 99555 Universal Check Valve, Plastic, Fits all 1-1/4-Inch or 1-1/2-Inch MIP or FIP

By now you are probably very tired of the answers to questions being, “Well, that depends…” but in the case of this one, the same answer applies. Just as is the case with a lot of products, the lifetime of a check valve depends on a lot of things. These include how often it is used, the age of the valve (and pump), and more.

These include:

Quality of the product. Needless to say, some products are simply made better than others. This being the case, those products that are better made will probably last longer than those that aren’t. Sometimes, however, some products will surprise you with a longer life than you ever expected. As a check valve gets older, it would be better to check them more often to ensure they are working.

Long time, no water. Sump pumps and check valves were made to pump water. Combine that with the types of materials that these are usually made with, and you will have a recipe for a leak or complete failure. Needless to say, without water running through your sump pump in a while, the parts will often corrode and a leak will develop eventually. Again, sometime you will be surprised, but generally speaking, these things hold true. It is best to watch these parts to make sure that they last their intended lifetime, but sometimes you will be surprised.

Debris and clogs. Sump pumps and pits are one of those things that often end up with debris in them. Mechanical parts also get dirty. Float switches also tend to get jammed. In cheaper models, switches also often get jammed. Add all of these elements up, and you have a prescription for a sump pump that will need repairs or in the worst cases, replacement. These things will surprise you, however, so if you are good about maintenance, chances are good that they will last longer.

Now for the verdict: in most cases, a check valve will last approximately 10 years. If you are careful, and you are attentive to maintenance, you will probably add approximately five years more to the lifetime of your check value and pump. After that, and God willing, you might have a check valve that will last longer than that, but that’s not the way to bet. Just as is the case with any appliance, stories are replete with both success and failure.

Sump pump check valves run in the price range of $18 to $30. For that price, it is better to replace it instead of leaving things to chance and finding one day that your house or office is now a swimming pool. Fun. Fun.

Sump Pump Check Valve Leaking

PM and Inspection check valve on closed drain sump pump process: check for leaking.

It doesn’t matter whether you are talking about a valve in a car, a human heart, or a sump pump, sometimes valves leak. This includes check valves. The good news in this is that it’s a lot easier to determine whether the check valves in a sump pump is leaking than in a car or even a human heart because all you have to do is to feel of the pipes. If you can feel the movement indicating that the water is heading in the right direction, chances are good that the check valve isn’t leaking.

If, on the other hand, the pump doesn’t appear to be working, that’s okay too, since check valves are relatively easy to replace, and yes, you read that right. Replace, since it really isn’t one of those kinds of things that anybody can fix. It might be a hassle, but if you are relatively handy with tools, you can replace it yourself. If not, call a plumber, since he is probably your best bet for a smooth-running check valve.

How Far Above Sump Pump Should a Check Valve Go?

This is another case of the authorities getting involved, but whether your sump pump is horizontal or vertical, the check valve should be located about 10 inches above the pump. You should check with your municipal government, however, since they often have requirements that must be met. Better safe than sorry. According to most experts, 10 inches is an average that most of them shoot for. When it comes to differences, however, there doesn’t seem to be much if any variance in the resulting lifetime.