Grundfos Submersible Pumps for Wells and Cisterns

How to choose the right submersible pump?

To avoid making a mistake in your purchase, you need to know three key data about your system: the diameter of the well, the depth of the water, and the amount of water you need.

1. The Diameter of the Well

It's the physical constraint.

• Do you have a 3" (80-90mm) well? Your only choice is the Grundfos SQ .
• Do you have a standard 4" (100-110mm) or wider well? You can choose either the SQ (which fits comfortably) or the SP (more robust).

2. Grundfos SQ vs Grundfos SP: The duel

Many customers are undecided between these two icons. Here are the differences:

• Grundfos SQ (Smart): This is an "electronic" pump. It has a permanent magnet motor that spins very quickly. Advantages: No external electrical panel required (it's all built-in), it's not affected by power surges, and it stops if the water runs out. Disadvantages: The electronics are inside the well (if it breaks, you have to dig it up).
• Grundfos SP (Industrial): This is a "mechanical" pump. Advantages: Indestructible, all-steel, repairable anywhere. Disadvantages: Requires an external control panel (purchased separately) with level probes or amperometric control to prevent it from burning out.

Frequently Asked Questions (FAQ)