GRUNDFOS · HORIZONTAL MULTISTAGE PUMP
CM 25-A — Cast Iron / 304 Stainless Steel
Horizontal multistage end-suction pump; cast iron pump housing with 304 stainless steel chambers and impellers. 2 models from CM 25-1 to CM 25-2, 5.4 to 8.6 HP, 2 in NPT(F) ports, AQQE (EPDM) or AQQV (FKM) shaft seal.
90-173 ft (38-75 PSI) Max Head · 161.3-161.4 GPM Max
5.4-8.6 HP
208-230/440-480V 3Ph
2 in NPT(F) Ports
End Suction, Top Discharge
Close-Coupled Motor, IP55
145 PSI Max Operating Pressure
NSF/ANSI 61
86-119 lb Weight
Overview
The CM 25-A is a compact, close-coupled horizontal multistage pump: suction enters at the end, discharge leaves at the top, and the pump is close-coupled to its motor on a common base. The pump housing and base are cast iron (ASTM A48-25A); chambers, impellers and shaft are stainless steel (AISI 304). Grundfos rates the CM 25 at 116 GPM nominal duty; size it from the performance table below.
- 2 models, CM 25-1 to CM 25-2, 5.4 to 8.6 HP
- Supply: 208-230/440-480V 3Ph
- 2 in NPT(F) suction and discharge; optional Grundfos flange, Victaulic and Tri-Clamp connection sets are listed separately
- AQQE (EPDM) or AQQV (FKM) shaft seal, silicon carbide faces
- Maximum operating pressure 145 PSI
What Ships and What It Needs to Run
Included: the CM 25 pump and its motor, factory-assembled as one close-coupled unit.
Optional: Grundfos flange, Victaulic or Tri-Clamp connection sets for the NPT ports.
Suction and discharge piping, valves, power supply, disconnect and motor protection: sized to your system and ordered separately.
Genuine Grundfos equipment, factory-new in original packaging — sold and supported by Watermain Supply, an independent industrial supplier.
Warranty: 24 months from date of installation, but not more than 30 months from date of manufacture (Grundfos limited warranty). Grundfos repairs or replaces its own product; costs of removal, installation and transportation are not covered, and products sold but not manufactured by Grundfos carry their own manufacturer’s warranty.
Specifications
| Specification |
Value |
| Nominal flow |
116 GPM (Grundfos nominal duty) |
| Shut-off head range |
90 to 173 ft (38 to 75 PSI) |
| Motor power range |
5.4 to 8.6 HP |
| Supply |
208-230/440-480V 3Ph |
| Motor |
Close-coupled, 2-pole, IP55, 60 Hz |
| Suction and discharge ports |
2 in NPT(F); end suction, top discharge |
| Maximum operating pressure |
145 PSI |
| Shaft seal |
AQQE (silicon carbide / silicon carbide, EPDM) or AQQV (silicon carbide / silicon carbide, FKM) |
| Liquid temperature |
−4 °F to 194 °F |
| Pump orientation |
Horizontal |
| Approvals |
cURus; NSF/ANSI 61 drinking water (Grundfos product data) |
Models & Performance — Will It Do What You Need?
Find the pressure you need at your flow and pick the first model that reaches it. Pressure at flow in PSI, one row per model and motor.
CM 25-1 to CM 25-2 · 2 curves
| Model (HP) |
0 GPM (Shut-off) |
32 GPM |
80 GPM |
120 GPM |
160 GPM |
| CM 25-1 (5.4 HP) |
38 |
39 |
38 |
34 |
25 |
| CM 25-2 (8.6 HP) |
75 |
75 |
75 |
69 |
53 |
Pressure the pump develops at each flow, in PSI, rounded down (feet = PSI × 2.31). Shut-off is read from the Grundfos curve at zero flow. Flow columns are read from the curve on the Grundfos 60 Hz chart for each model and motor (water at 68 °F), digitized and rounded down, at 20%, 50%, 75% and 100% of 160 GPM, the last regular flow every curve in this listing reaches; the curves end at 161.3 to 161.4 GPM. On CM 25-1 (5.4 HP), CM 25-2 (8.6 HP) the curve rises above its zero-flow head at low flow (by up to 3 ft); the flow columns follow the curve. Full Grundfos curves are in the product images.
Before You Buy — The Limits That Decide the Fit
| Check |
What decides the fit |
| Duty point |
The model’s pressure at your flow must cover the system’s total head; shut-off is the head at zero flow (on some models the curve rises slightly above it at low flow; the table shows it). |
| Working pressure |
Inlet pressure plus the pressure the pump adds must stay within 145 PSI. |
| Liquid temperature |
−4 °F to 194 °F. |
| Shaft seal |
AQQE has EPDM rubber parts and AQQV has FKM; choose the rubber that suits the pumped liquid. |
| Power |
Supply at the voltage and phase shown in the selected option. |
| Connections |
2 in NPT(F) threaded ports; flange, Victaulic and Tri-Clamp sets are optional. |
Applications
Pressure boosting in buildings and small water supply systems, HVAC heating and cooling circulation, washing and cleaning, water treatment, light industrial process water and irrigation (Grundfos CM range applications).
Materials of Construction
| Component |
Material |
| Pump housing and base |
Cast iron, ASTM A48-25A |
| Chambers and impellers |
Stainless steel AISI 304 |
| Shaft seal faces |
Silicon carbide / silicon carbide |
| Seal and O-ring rubber |
EPDM (AQQE) or FKM (AQQV) |
