Why Does My Sump Pump Keep Running?

Reasons the Sump Pump Keeps Running

Jammed Sump Pump Float Switches

Sump pump systems feature a "float switch" designed with a lightweight material, which many are filled with air, to float upwards as water rises in your existing sump pit. When the float switch rises to a certain level, it triggers a switch, turning your sump pump on. As the water drops, the float switch lowers again, turning the switch off.

The most common reasons why a house sump pump keeps running continuously are when the sump pump float switch is stuck in the "on" position in your sump pit. This will cause it to run even when all the water has been removed, which will burn out the pump. These switches usually fail for two reasons:

• The sump pump moves in the pit: As house sump pumps operate, they vibrate. Over time, this vibration will cause the sump pump to move around the pit. If the float switch is pressed against the side of the liner, it can become forced into the "on" position, causing it to run nonstop.
• The float switch becomes stuck: The float switch can hook onto something in the sump pit, such as a wire or pipe. Alternatively, debris in the sump liner may jam the float switch in the "on" position.

If the float switch is the reason why your water pump won't shut off, our local dealers can provide more information about sump pump switch replacement or an entire system upgrade.

Faulty Check Valve

The house sump pump prevents basement flooding by collecting excess water and pumping it upwards into a discharge line, which directs the water out of your house. These discharge lines often run straight upwards for five to eight feet.

However, if the sump pump system empties the liner of water and turns off, the water in that length of pipe will fall straight down again. If it lands back in the pit, your sump pump may turn back on and shoot it back up, starting an endless cycle.

To prevent this, contractors install a "check valve" in the discharge line that stops water from flowing back to the pump. If there is an issue with the check valve, your pump may pump the same water out continuously.

Drainage System & Plumbing Issues

Many plumbing issues can cause a sump pump to keep running. If you have a broken sprinkler system somewhere underground, it could create a continuous supply of water for your system to pump. Other plumbing leaks, such as a broken sewer pipe underneath your home, may also be the cause.

These problems can also lead to foundation heaving and other damage to your home. If this is the case, contact a waterproofing professional right away.

Alternatively, you may have a sump pit that is too big and deep. You only need to keep the water out of your basement. If the pump is too deep, it may run constantly and remove more water than needed.

Home is Above the Water Table Line

There are rare cases where the house was built in the wrong spot. Your home may have been built just above a water table line. When that water table rises due to heavy rains or the wet season, it might be above your basement floor.

In other scenarios, a natural rock shelf might direct groundwater to collect around your home. Or a natural underground spring might be sending an endless supply of water into the soil around your foundation.

In these cases, your house sump pump struggles against the entire water table and, while it might keep your basement dry, it will run nonstop to do so.