GRUNDFOS · VERTICAL MULTISTAGE CENTRIFUGAL PUMP
CR 1s
Vertical multistage centrifugal pump in cast iron and stainless steel. 19 models from CR 1s-2 to CR 1s-27, 1/3 to 2 HP, 1 in NPT oval-flanged or 1 1/4 in ANSI flanged ports, HQQE or HQQV cartridge shaft seal.
53-746 ft (23-323 PSI) Max Head · 5.6-5.7 GPM Max
1/3-2 HP
1Ph or 3Ph · 115/208-230V or 115/230V 1Ph · 208-230/460V 3Ph
1 in NPT Oval or 1 1/4 in ANSI Ports
In-Line Suction and Discharge
NEMA 56C TEFC Motor
232-363 PSI Max Operating Pressure
cURus
45-114 lb Weight
Overview
Vertical, multistage centrifugal pump with suction and discharge ports on the same level, so it drops into a straight pipe run. The pump head and base are cast iron; all other wetted parts are stainless steel (EN 1.4301, AISI 304). The CR 1s is the smallest CR size, rated at 4.8 GPM (Grundfos’s nominal duty) for low-flow, high-pressure duty; size it from the performance table below rather than from the model number.
- 19 models, CR 1s-2 to CR 1s-27, on NEMA 56C TEFC motors, 1/3 to 2 HP
- Single-phase 1/3 to 2 HP (115/208-230V, 115/230V) or three-phase 208-230/460V on every model
- Oval flanges tapped 1 in NPT (included) on CR 1s-2 to CR 1s-17, or 1 1/4 in ANSI flanges (250 lb)
- HQQE (EPDM) or HQQV (FKM) cartridge shaft seal with silicon-carbide faces
- Maximum operating pressure: Oval NPT versions 232 PSI; ANSI versions 363 PSI
What Ships and What It Needs to Run
Included: the CR 1s pump end and its NEMA 56C TEFC motor, factory-assembled as one complete pump. Oval-flange versions include the two oval flanges, tapped 1 in NPT.
ANSI companion flanges required, ordered separately. On the ANSI versions Grundfos supplies the companion connection as a separate set (flange sets: two flanges, two gaskets, nuts and bolts), sized 1 1/4 in.
Suction and discharge piping, valves and controls: 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 |
| Rated flow at 60 Hz |
4.8 GPM (Grundfos nominal duty) |
| Shut-off head range |
53 to 746 ft (23 to 323 PSI) |
| Motor power range |
1/3 to 2 HP |
| Supply |
1Ph 115/208-230V, 115/230V; 3Ph 208-230/460V |
| Motors |
NEMA 56C C-face, TEFC, 2-pole |
| NEMA frame |
56C |
| Frequency |
60 Hz |
| Suction and discharge ports |
In-line; 1 in NPT or 1 1/4 in |
| Connections |
Oval flanges tapped 1 in NPT (included); 1 1/4 in ANSI flanges, 250 lb |
| Maximum operating pressure |
Oval NPT versions 232 PSI; ANSI versions 363 PSI |
| Liquid temperature |
−4 °F to 248 °F with HQQE; −4 °F to 194 °F with HQQV |
| Maximum ambient temperature |
104 °F |
| Pump orientation |
Vertical |
| Approvals |
cURus |
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.
CR 1s-2 to CR 1s-13 · 12 models · 1/3 to 1 HP
| Model (HP) |
0 GPM (Shut-off) |
1.1 GPM |
2.8 GPM |
4.1 GPM |
5.5 GPM |
| CR 1s-2 (1/3 HP) |
23 |
24 |
22 |
19 |
15 |
| CR 1s-3 (1/3 HP) |
36 |
35 |
32 |
28 |
23 |
| CR 1s-4 (1/3 HP) |
48 |
48 |
44 |
38 |
30 |
| CR 1s-5 (1/3 HP) |
60 |
59 |
54 |
47 |
37 |
| CR 1s-6 (1/2 HP) |
72 |
71 |
65 |
58 |
45 |
| CR 1s-7 (1/2 HP) |
84 |
81 |
73 |
63 |
49 |
| CR 1s-8 (1/2 HP) |
96 |
92 |
82 |
70 |
53 |
| CR 1s-9 (3/4 HP) |
108 |
106 |
97 |
84 |
65 |
| CR 1s-10 (3/4 HP) |
119 |
116 |
104 |
89 |
67 |
| CR 1s-11 (3/4 HP) |
131 |
128 |
117 |
103 |
80 |
| CR 1s-12 (3/4 HP) |
142 |
138 |
123 |
105 |
78 |
| CR 1s-13 (1 HP) |
158 |
151 |
136 |
116 |
87 |
CR 1s-15 to CR 1s-27 · 7 models · 1 to 2 HP
| Model (HP) |
0 GPM (Shut-off) |
1.1 GPM |
2.8 GPM |
4.1 GPM |
5.5 GPM |
| CR 1s-15 (1 HP) |
181 |
172 |
153 |
130 |
97 |
| CR 1s-17 (1 1/2 HP) |
207 |
202 |
181 |
156 |
119 |
| CR 1s-19 (1 1/2 HP) |
230 |
224 |
200 |
172 |
131 |
| CR 1s-21 (1 1/2 HP) |
254 |
246 |
219 |
188 |
142 |
| CR 1s-23 (1 1/2 HP) |
277 |
267 |
238 |
203 |
153 |
| CR 1s-25 (2 HP) |
301 |
297 |
276 |
248 |
204 |
| CR 1s-27 (2 HP) |
323 |
322 |
298 |
265 |
213 |
Pressure the pump develops at each flow, in PSI, rounded down (feet = PSI × 2.31). Shut-off is Grundfos’s published maximum head for each model. Flow columns are read from the Grundfos 60 Hz curve for each model (water at 68 °F), digitized and rounded down, at about 20%, 50% and 75% of 5.5 GPM, the last regular flow every curve in this listing reaches; the curves end at 5.6 to 5.7 GPM. Full curves are in the product images. The CR 1s-2 curve reads 58 ft at zero flow against 53 ft published; the published shut-off is shown and the flow columns follow the curve. Grundfos’s published duty point sits below its own curve by more than 3% of shut-off on CR 1s-2, CR 1s-6, CR 1s-11, CR 1s-25, CR 1s-27 (by up to 63 ft at the rated flow); the table follows the curve. Grundfos’s published duty point sits above its own curve by more than 3% of shut-off on CR 1s-15 (by up to 16 ft at the rated flow); the table follows the curve.
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 most it can make, at zero flow. |
| Working pressure |
Inlet pressure plus the pressure the pump adds must stay within the maximum operating pressure: Oval NPT versions 232 PSI; ANSI versions 363 PSI. |
| Liquid temperature |
−4 °F to 248 °F with HQQE; −4 °F to 194 °F with HQQV. |
| Power |
Single-phase or three-phase supply at the voltage shown in the selected option. |
| Connections |
ANSI companion flanges (1 1/4 in) ordered separately; oval-flange versions ship with 1 in NPT flanges. |
| Shaft seal |
HQQE has EPDM rubber parts and HQQV has FKM; choose the rubber that suits the pumped liquid. |
Applications
HVAC heating and air conditioning, district heating and cooling, plumbing pressure boosting, industrial water supply and transfer, process liquids, wash and clean, water treatment, irrigation and ground water transfer (Grundfos CR range applications).
Materials of Construction
| Component |
Material |
| Pump head and base |
Cast iron |
| Other wetted parts |
Stainless steel EN 1.4301 (AISI 304) |
| Bearings |
Silicon carbide |
| Shaft seal faces |
Silicon carbide / silicon carbide (HQQ cartridge seal) |
| Seal and gasket rubber |
EPDM (HQQE) or FKM (HQQV) |
