When a home inspector is inspecting the basement or crawlspace of a home, they may encounter something called a sump pump. A sump pump is a small pump that sits in a sump pit/crock and helps keep the area under the structure dry and helps prevent flooding. Water enters the perimeter drainage system or by water moving through the soil. In a basement, for example, the sump pit/crock is located below the basement slab. It typically has a plastic liner but may be concrete or have earth walls.
The electric sump pump is located in or above the sump pit/crock. Water is pumped away from the house through a discharge pipe. Some areas may allow the sump pump to discharge into the storm sewer but more and more jurisdictions are getting away from allowing this. It should never discharge into the sanitary sewer.
Ideally the sump pump will have a dedicated circuit breaker for the outlet that the pump gets plugged into. You may encounter a sump pump that is plugged into a GFCI protected receptacle but from my experience it is best that the sump pump be plugged into a normal properly grounded receptacle without GFCI protection. The reason behind this is that not many people pay attention to the sump pump/pit, and if the GFCI trips, they don’t know that the basement/crawlspace could flood causing damage. The codes may vary from this opinion and state that any receptacle in an unfinished basement or a crawlspace should have GFCI protection.
The home inspector should test the pump for operation. It can be a pedestal-style pump which has the motor mounted on a shaft sitting above the water level. A lever will stick out of the pit/crock. To test the operation of the pump, pull up on this lever. Be careful when doing this, as electrical safety is something to consider.
In addition to the pedestal style sump pump, the home inspector may encounter a submersible type, which sits below the water level in the sump pit/crock. To test this type of sump pump, use a plastic or wooden stick to pull up on the pressure switch or float. Another way to test each kind of sump pump is to run the water into the pit/crock with a hose or pour water from a bucket into the sump pit/crock to activate the float.
The sump pump motor should run quietly and should discharge water; you may even see a check valve on the discharge line. The pit/crock should be covered and kept free of silt buildup and debris.