Check the float switch condition
The level sensor is located beneath the filter housing and above the inlet to the pump. Make sure that it is able to move freely.
Turn off power to the Backup in a Box unit and the pump. Remove the level sensor from the tank and check if any debris is preventing the sensor from moving up and down the short stem that it is located on.
Clean / Remove any debris
Turn on the pump and Backup in a Box and wait 45 minutes to see if the water stops flowing.
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