The Grundfos 16S20-18 (product number 10010018) is a SP3A stainless steel submersible pump end rated 17.6 US gpm at 367.5 ft across 18 stages. This is the bare pump end only — it is supplied without a motor and requires a 2 HP submersible motor with a 4″ NEMA flange.
Pump end only — motor not included. Requires a separately ordered 2 HP Grundfos submersible motor. Contact us if you need the complete pump-and-motor assembly.
Performance Curve
Official Grundfos curve — 60 Hz, water at 68 °F. Head (H) and efficiency (η) against flow (Q); lower chart shows power and NPSH required.
Performance & Hydraulic Data
| Rated flow | 17.6 US gpm |
| Rated head | 367.5 ft |
| Stages | 18 |
| Pump speed (data basis) | 3450 rpm |
| Pump type | SP3A |
| US designation | SP3A-18 |
| Maximum operating pressure | 217.56 psi |
| Maximum outlet pressure | 240.76 psi |
| Built-in return valve | Yes |
| Curve tolerance | ISO9906:2012 3B |
Materials of Construction
| Pump housing | Stainless steel — EN 1.4301 — AISI 304 |
| Impellers | Stainless steel — EN 1.4301 — AISI 304 |
Installation & Connections
| Discharge connection | 1 1/4 NPT(F) |
| Motor diameter | 4 inch |
| Minimum borehole diameter | 4.13 in |
| Overall length | 20.9 in |
| Liquid temperature range | 5 °F to 140 °F |
Motor Requirement
| Motor required (not included) | 2 HP |
| Motor flange | Grundfos |
| Shaft end | SPLINE |
| Frequency | 60 Hz |
Approvals, Weights & Identification
| Approvals | CULDWUS,CCSAUS |
| Drinking water | PROP65 |
| Grundfos product number | 10010018 |
| EAN | 5700390303556 |
| Net weight (pump end only) | 12.8 lb |
| Gross (shipping) weight | 15.4 lb |
| Country of origin | United States |
| HS / customs tariff code | 8413.70.2004 |
Typical Applications
Well and borehole water supply • groundwater abstraction • irrigation • pressure boosting • livestock and rural water • industrial process water.
Need help? Contact ForeverPure Place for pricing, lead time, accessories, or help selecting the correct model for your application.
