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Check Your Sump Pump

A sump pump is many homeowners’ first line of defense against getting water in the basement.

Sump pumps are available in two basic models: upright (commonly called a pedestal) and submersible.

The sump, which is the pit where the pump sits, may be connected to drain tile that drains the footings of the house, the area under the entire basement or just the area where the sump is located. Many houses have tile installed only around a portion of the house. The water that drains into the sump must be removed with a sump pump.

The pedestal pump's motor is on top of the pedestal and the pump is at the base, which sits on the bottom of the sump. The motor is not meant to get wet. A ball float turns the pump on and off. One advantage of this type of pump is that the on/off switch is visible, so you can see the ball float's action.

Submersible pumps are designed to be under water on the bottom of the sump. The on/off switch is attached to the pump.

Pumps have three main types of on/off controls:

  • Ball float, which is attached to the pump and connected to an internal watertight switch
  • Sealed, tethered float switch with an on/off setting that is adjustable by changing the length of the tether
  • Diaphragm, which senses the water level and turns the pump on and off

 Both types of pump should have a check valve on the water discharge pipe so water doesn't flow back into the sump when the pump shuts off. Water flowing back into the sump can cause the pump to turn on and off more frequently than necessary, which decreases the life of the pump.

 To check the pump:

  • Make sure the discharge pipe on the side of the house is not frozen shut or plugged and that it directs water away from the house.
  • Make sure the pump is plugged in.
  • Remove the lid (if the sump has one) and use a flashlight to check if the sump is clean and the pump inlet screens are not plugged.
  • Slowly pour water into the sump. Try to simulate the speed that water normally would flow into the sump.
  • Watch the on/off switch's action and listen to the pump. Make sure the pump turns on and off at least twice. If something doesn't work or sound right, fix it as soon as possible.

 Here are some answers to frequently asked questions:

 Q: Can you burn the pump out if the outdoor pipe is frozen shut, or will the pump shut off automatically?

 A: Most pumps will not burn up, but they can overheat in this situation. Almost all sump pump motors have thermal protection built in, but the submersible type needs water around the motor for cooling. If they do overheat, shut them off and let them cool. The thermal relay will reset.

Q: What size pump should I have for my house?

 A: There is no "correct" size. The horsepower requirement depends on several factors, including the length of drain tile connected to the sump, the lift from the sump to the discharge pipe on the side of the house and the length of hose or pipe outside the house. A one-third horsepower pump will work for most houses, but if you have more than 40 feet of pipe outside the house, use a pump with more horsepower (one-half, three-fourths or even 1 horsepower).

 Q: Do sump pumps have filters that need to be cleaned or replaced?

 A: They do not have filters, but they do have screens or small openings where the water enters the pump. These sometimes can be plugged.

 Q: Can or should you pump into a sewer drain or basement floor drain?

 A: No. If you have a septic system, do not pump sump water into the basement floor drain. During wet conditions, the septic system's drain field usually is saturated and struggling to handle the normal flow of water from the house. Adding to the flow with a sump pump can damage the septic system. Even if you are connected to a public sanitary system, the sump should not be pumped into a floor drain. Putting additional water into the public sewer during flooding can contribute to sewage backflow. As a result, some cities have regulations against pumping into their sanitary sewer system. Some communities allow sump water to discharge into the sanitary sewer but only for specified periods during the winter.

Q: Where should the sump pump drain hose run?

A: Preferably, discharge sump water at least 20 feet from the house so it drains away from the house. Also, do not direct it into a neighbor's lot, window wells or a septic system drain field.

Q: Can I replace a defective sump pump, or do I need specialized tools or a plumber?

A: Almost all sump pumps come with a list of required tools and directions for installation. Replacing a sump pump should not be difficult for the "average" person.

For more tips on getting your sump pump ready to handle spring and summer water, view a video at www.ag.ndsu.edu/flood/home/sump-pump-tips or visit www.ag.ndsu.edu/flood/home/sump-pump-questions.

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