The Basics of Sump Pumps

By HomeAdvisor

Updated September 27, 2017

Sump pump enclosure

If you live in a very flat area of the country, a place of low elevation, or a region with a high water table, then you’re probably at risk for flooding—there’s a reason these places are called floodplains. In fact, after heavy rains, you’ve probably already undergone or heard of people’s experiences with flooded basements. It doesn’t take much for water to cause some serious harm; in fact, just a couple inches of standing water can create thousands of dollars in damage. So in order to avoid a swamped sublevel, the best way to prevent the deluge is an investment in a quality sump pump.

Just One Job

A sump pump has one sole duty in this world: to take excess water away from your home. It may seem silly to pay money for a machine that only performs a simple, single task. But water can be a very dangerous threat to the home. Here’s what happens: You have tile drains wrapping all the way around your house which captures surplus water from rainfall or heavy snow melts. When this tile gets overwhelmed, it directs the overflow to a central location in your basement called a sump. A sump is simply a well that looks like a small pit in your sub-floor where water collects.

But if this pit becomes full, you have two problems: the well may overflow into your basement, but more likely the problem is the tile around your house is just sitting full of water. And with this tile being located right next to your foundation, water may eventually seep into your basement through cracks and fissures. This is where the sump pump comes in. When water in your sump reaches a critical level, this machine will force the liquid out through a pipe that leads away from your foundation and into the city storm drain.

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How it Works

These devices come equipped with a “float”, which works like a backwards toilet. Unlike a toilet float, which stops the commode once water reaches a certain level in the tank, this particular float turns on the machine and activates the pumping once water rises high enough. There are several different types of models to choose from, so make sure you select one that works best for your particular needs.

  • Pedestal: This model sits upright above the well, bringing with it lots of pros and cons. Its motor is out of the water and can’t get wet, which makes it louder but also longer lasting since it’s not sitting in water all the time. It’s also quite a bit cheaper.
  • Submersible: It actually rests inside the pit and becomes submerged by the incoming water. It is tightly sealed against debris and infiltration, which makes it durable and very reliable. It’s more expensive (around $300), but due to its consistency, this model is often recommended for finished basements.
  • Battery Backup Sump Pump: A huge problem with many models is that hey only activate when it rains, but yet they still run on electricity. You can probably foresee the problem: heavy thunderstorms bring on the rainfall and often create power outages at the same time. A disabled sump pump during a power surge is one of the main causes for flooded basements, especially if the homeowners happen to be out of town during the storm.

So this is why battery backup sump pumps were created: they detect when the product is not receiving electricity and due to their independent batteries, these support systems can take over the job. They’re expensive (up to $700), due to their gel-pack technology, but they cycle up to 9,000 gallons without recharging, which means if you’re out of town for five days, you shouldn’t have to worry about coming home to a swamped basement.

Sump Pump Repair

They aren’t invincible. They’re machines and will need some maintenance. Here are some common problems and various sump pump repairs to be aware of:

  • Float Triggers: Floats are the most common problem. If it gets caught on something and can’t detect the rising water level, the whole apparatus becomes useless. Plus, over time, these float triggers may burn out and will need to be replaced. So check it out: clean out any debris you see floating in the water (it may help to set the machine up on bricks to avoid direct contact with the dirt collecting on the bottom of the pit), and every few months pour water into your sump to see if the float responds properly.
  • Check Valves: These one-way valves make sure that once pumping stops, water will not back flow back into the sump, creating additional risks and shortening the lifespan of the appliance. If air gets into this valve, it could become locked up. So make sure to get it fixed right away: there’s no point in having a machine that hums but doesn’t pump.
  • Primary Failure: Every 8-10 years, you may need to replace your primary pump. And if it’s been sitting in water all that time, it may rust up or simply burn out. Plus, it’s important to keep any machine running occasionally to avoid lock-up; so even during dry seasons, try to pour water into the well to occasionally activate it.
  • Improper Installation: Incorrect setup is the initial problem many homeowners encounter. The cost to replace a sump pump that was improperly installed is no small investment. Make sure to get professional advice when shopping around so you get the right size and horsepower for your home’s needs. Plus, if it isn’t properly installed, it loses all purpose. These experts ensure quality products, guaranteed installation, and thorough sump pump repairs, often offering a 1-year warranty on all their work.


  1. Elaine Woolf, January 14:

    My subpump dosent do much you have to shake it to get it to work

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