Submersible well pumps: a buyer's guide
Submersible well pumps work immersed in water, pushing it to the surface. Choosing the right one takes only a few, precise figures.
1. Well diameter
The first constraint: submersibles are rated in inches (4", 6", 8"…). The pump must fit the casing with margin. 4" is the domestic and agricultural standard.
2. Depth and dynamic level
What matters is the dynamic level (water level while pumping), not just the static one. Place the pump below the dynamic level but above the bottom, to avoid sucking sand.
3. Flow and head
Total head = lift from the dynamic level to the surface + any required pressure + losses. Multistage submersibles reach very high heads (tens or hundreds of metres).
4. Sand and materials
If the water is sandy, choose abrasion-resistant versions (stainless or technopolymer hydraulics). Sand is the number-one cause of early wear.
Grundfos models
The SP range (stainless) is the professional standard; the SQ/SQE is compact with built-in motor protection. See pumps for a well and the agriculture and irrigation sector, or use the selector.
Häufige Fragen
What pump diameter do I need for a well?
It depends on the casing: the pump must fit with margin. 4" is the domestic and agricultural standard; wider wells use 6" or 8".
How deep should the pump sit in the well?
Below the water's dynamic level (while pumping) but well above the bottom, to avoid drawing in sand and sediment.