How A Sump Pump Works and Why It’s Important

If you live near the water or an area where the water table tends to rise easily with heavy rains, you may already be familiar with what a sump pump is and what it does. The sump pump helps get that rising water out from under your foundation before it starts to seep into your basement or lower floors. There are many different kinds of sump pumps, some that you can just manually sit in the sump (a small pit beneath the foundation of your home) or others that are physically installed into the foundation and don’t move, but they all generally work the same way.

How Does a Sump Pump Work?

Your sump pump is usually installed in a 2-foot-deep pit, or sump, in the base of your foundation. This pit gradually fills with water as the water table rises or with heavy rain. As the sump starts to fill with water, a floating switch will start to rise with the water level. That switch will eventually complete a circuit when the water rises high enough, triggering the pump to turn on. With the sump pump engaged, it will start pumping the water out of the sump and out from below the foundation. There’s also a one-way check valve just above the top of the sump that prevents the backflow of water back should the pump fail or the water level drops low enough for the pump to disengage. Depending on the type of pump, there may be a few more moving parts in terms of how your pump specifically moves the water out of the sump, but the overall setup for any sump pump will be pretty much standard.

Sump pumps also require electricity to operate. If you lose power during a storm or with flooding (which can be extremely common in strong storms that would kick the sump pump into gear), your pump is definitely going to struggle to keep up with the rising water. It’s also important that the outlet you plug your sump pump into has a GFCI, or ground fault circuit interrupter. A GFCI can help prevent a person from getting electrocuted by sensing a change in the electrical output flowing out of the circuit and shutting off the power if it determines there is more electricity flowing out of the outlet into the circuit than there should be. These are usually installed in outlets near appliances that rely on water such as dishwashers, washing machines, and a sump pump. You should also connect your sump pump to a backup power supply since it won’t be able to function if the power to the main outlet goes out.

Types of Sump Pumps

There are a few different kinds of sump pumps, and they all work slightly differently in terms of setting them up. There are two types of sump pump, pedestal pumps and submersible pumps, and either can function as a main pump or a backup pump. The main pump is going to be what handles the regular load, keeping your sump empty most of the time. The backup pump is there to chip in if there’s too much water for the main pump to handle all at once or if the main pump fails for some reason.

Submersible pumps usually sit right inside the sump pit, and function once underwater. They’re much bulkier than pedestal pumps, but they are generally quieter and a little more reliable. Due to how they sit in the sump, they also can be very difficult to access for repairs or maintenance.

Pedestal pumps are usually tall and thin, with the motor sitting on top of the unit, like on a pedestal, while the intake or impeller is at the bottom of the unit. It’s a lot smaller than the submersible unit and lighter, easily removed from the sump for repairs or maintenance as needed. Unlike the submersible pumps, the motor is not meant to get wet, and since it sits above the sump on top of the unit, pedestal pumps tend to be a lot louder than submersible pumps.

The backup pumps tend to run on one of two different fuels. The first is the water-powered backup pump. These pumps don’t run on electricity; they actually use water pressure to power the pumping unit. While they have the advantage of being able to run infinitely without running out of power, they aren’t without their disadvantages. They do need a supply of high-pressure water to run, generally from something like city water lines. In homes that rely on well water or low-pressure water supplies, water-powered backup pumps won’t run properly. These types of pumps also tend to be a lot more complicated to install properly, making troubleshooting a faulty pump a lot more difficult.

Battery-powered pumps, on the other hand, run on a large battery, something akin to a car battery, and only kick on when the main pump fails to help pick up the slack. These are the most common kind of backup pump and are relatively easy to install.

Lastly, there are combination pumps that have both a main pump and backup pump built right into the same unit. This might be a more cost-effective option than buying two entirely separate pumps and installing them together. The downside to these combination pumps is that they tend to be larger than individual main pumps and might not fit into smaller sump pits.

What Kind Do I Need?

In order to determine the kind and size of sump pump you’ll need, you’ll have to determine the flow rate of the water. Wait for a rainy day and wait for your existing sump pump to shut off (if you have one). From there, unplug it from all power sources and track the water level for one minute. For an 18-inch diameter sump, one inch is equal to one gallon of water, for a 24-inch diameter sump, one inch is equal to two gallons. Next, multiply this number by 1.5 to account for intake during heavy storms. Sump pumps generally need to run off of at least 1/3 horsepower to properly pump out water from the sump, though this could change based on how much water you regularly take in.

Once you have this information, the rest comes down to the size of your sump and a bit of personal preference. If you’re looking to purchase a new sump pump or replace an old one, the professionals at AJ Danboise Plumbing, Heating, Cooling & Electrical can help make sure you’re getting the best pump for your home. [Company_name] certified technicians can evaluate and measure your sump, get an estimate on how much horsepower your unit will need to keep up with the water filling your sump, and help with properly installing your new pump. They also offer other services like furnace repair, general plumbing, electrical work, installing water filtration systems, and boiler maintenance. If you’re having issues with your sump pump or having issues with any other major system in your home like your heating or plumbing, don’t hesitate: give the professionals at AJ Danboise Plumbing, Heating, Cooling & Electrical a call today for an inspection and an estimate.

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