Sump pumps.(College of Product Knowledge)

This is an updated version of the product training course introduced by SUPPLY HOUSE TIMES in 1979, authored by Don Arnold.

Though a sump pump can be used for other purposes, the two most common uses involve the removal of ground water from around the perimeter of a building foundation or the pumping of laundry discharge to a higher-level drain connection. In the case of the former, such an installation prevents seepage and flooding into basements and crawl spaces. Unlike most of the products covered in this course, sump pumps tend to be somewhat regional in their application: standard equipment in certain areas of the country, rarely used in others. Another way to define this is based on the construction of the foundation--whether or not there is a basement (or sub-grade crawl space).

THE SYSTEM: Before we look at the mechanical makeup of these products, let's look at the input and output aspects of an installation used for discharging ground water. First of all, if the sump pump is to dispose of ground water drainage, there must be a network of piping in the ground around and/or under the house to collect it. This usually takes the form of a loop of drain tile around the foundation. Drain tile is loosely jointed or perforated drainage piping material, constructed of clay, composition or plastic, which permits ground drainage to seep in. Such a loop is usually laid just outside the foundation footing in the case of new construction, or just inside the footing in the case of a retrofit installation. The water seeping into the drain tile is collected in a pit, called a sump, In the overall water-draining network, the sump is positioned at the lowest point, using gravity to get the water there. This water is removed by the pump when the level in the pit rises to a predetermined level, causing the float switch to activate. As the level drops, the float switch cuts out again, completing the cycle. Water is evacuated outside the building through a discharge line (most codes do not allow direct connection to the sanitary sewer system for ground water discharge). Laundry sump pump systems, on the other hand, do discharge into the sanitary sewer.

Let's move on now to examine each of the basic components in a typical sump pump installation

THE SUMP: You might be wondering what there is to say about a hole in the ground, but there's actually a bit more to it than that. Ideally located in the lowest portion of the basement, the sump usually has a minimum diameter of 18 inches and a depth of 24 inches. Actually, that part of the system properly called the sump is not the hole in the ground but rather a liner for that hole, typically constructed of concrete. clay, fiberglass, steel or polyethylene. The sump will have a solid bottom to support the pump inside, unless there is a problem with excessive ground water pressure against the basement floor. In this case, a gravel bottom must be used, and a solid base (such as bricks or a steel plate) should be provided as a base for the pump. Finally, there is a cover for the sump, the purpose of which is to keep possible odors and vermin in, and keep foreign objects like small children, for instance out. Such lids are typically specified to withstand a load of about 200 lb.

THE PUMP: In terms of basic design, there are two types of sump pumps offered today: submersible and pedestal. As in the case of submersible well pumps, the former is placed in its entirety--motor and all--right down in the water. This makes for a relatively compact assembly, with no mechanical parts protruding through the lid of the sump. The pedestal style of design uses essentially the same type of pumping components as the ...