Here’s Why Your Sump Pump Isn’t Working—and What to Do About It

Justine Harrington
Updated April 4, 2022
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Photo: Maskot / Getty Images


  • Most sump pumps last between seven and 10 years.

  • Routine maintenance is crucial to ensure maximum efficiency.

  • Common reasons for failure include clogs and taking in too much water.

  • Bring in the pros if you don’t know what's wrong with your pump.

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A good sump pump is invaluable for protecting your home during basement floods. But, what should you do if your trusty pump isn’t working? There are several reasons why your pump may be failing you. These are the most common sump pump problems and how to remedy them.

1. Power Failure

One of the most common reasons that sump pumps fail is an electrical power outage. In the event of a power outage, it’s important to have a backup generator on hand. Then, if you ever lose power because of a storm, you can manually turn this generator on to prevent flooding.   

2. Incorrect Installation 

If your sump pump is constantly running, there are three possible causes:

  1. It was installed incorrectly

  2. The pump is too big

  3. The pump is too small

For each of these reasons, it’s a good idea to get in touch with sump pump repair services near you to get your pump reinstalled or calculate the right size pump for your home. Your pro will weigh your capacity needs against horsepower to determine your next pump.

3. Too Much Water

It’s easy to overwork your sump pump in the event of flooding. If your pump is overflowing, try the following before calling a technician:

  • Restart the motor.

  • Pull the pump’s plug and let it sit for a few minutes before plugging it back in.

  • Inspect the discharge line and overflow valve for clogs.

If these troubleshooting tips don’t help drain the pit, you may have a faulty valve (the part that opens and closes to let water out of the pump). You should call in a professional to locate and check the valve to determine if a replacement is necessary. Diagnosing a faulty valve is pretty tricky, so it’s best to leave this one to the pros.

4. Lack of Maintenance 

As with any other system or major appliance in your home, maintenance is crucial to ensure maximum safety and efficiency. It’s important to know how to maintain your sump pump so it lasts longer. Be sure to clear the sump basin of debris, remove and clean the pump, and make sure the discharge pipe isn’t clogged. 

5. Stuck Sensor

If your pump isn’t turning on, this could be because of a faulty or stuck float sensor, which is the part that triggers your pump to turn on and off when the water level in the pit reaches a certain point. This is a fairly common mechanical issue that happens when debris jams the float or the pump shifts inside the basin (which causes the float that operates the sensor to become ineffective). 

Luckily, this is an easy fix—simply adjusting and cleaning your pump usually does the trick. Keep in mind float sensors only last about five to seven years, so a replacement may be in order if it's ineffective.

6. Clogs

Like many home systems, sump pumps can fall victim to debris like rocks, mud, and sticks. Be sure to check your sump pit for potential clogs every few months or after a heavy rainstorm. Ensuring your sump pump has a lid is your most effective defense against clogs, as lidless sump pumps will back up more often. 

7. End of Lifespan

Most sump pumps generally last between seven and 10 years. If you’re experiencing sump pump failure and your pump is over 10 years old, you may be beyond basic troubleshooting methods. Some sump pumps can last longer than this, but we recommend that you replace your pump after 10 years to be safe.) Knowing how much a sump pump replacement costs is crucial. 

When It’s Time To Call a Professional 

If you’ve tried all the sump pump troubleshooting techniques listed above and your pump still isn’t working properly, it’s time to bring in the pros. Hire a sump pump contractor near you to ensure that your basement (and your home) stays protected. 

And, knowing how much a sump pump replacement costs is crucial. On average, sump pump repairs will cost $510, according to HomeAdvisor. But if your pro deems replacement a better option, it’ll cost $275 to $1,000 to get a new sump pump installed.

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