The main purpose of a sump pump is to get rid of excess ground water that accumulates around a basement that is below the water line. The basement should have a drain tile around it to collect ground water and bring it to the sump in the basement. You can rent a sump pump even after your home has flooded with water or if you are going to a worksite where one will be needed to get the job done efficiently.
Automatic and manual models are available with either gravity-fed or self-priming operation. Capacity is rated on the amount in gallons-per-hour can be pumped as well as the "lift" pressure generated that tells how high the liquid is to be pumped. Some models offer battery back up in case of a loss of power. The pumps are designed in two different styles; both doing an equally good job.
In a submersible pump (pictured), the motor and the pump are sealed in one unit. The unit fits into the pit in the floor to pump out the water. The other model available is referred to as a pedestal pump. It has the motor mounted on a column above water level, and the base is fit into the pit.
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