Minimum Continuous Duty Flow Rates [Gpm]; Check Valves - Grundfos CR 1s Instrucciones De Instalación Y Operación

8.10 Minimum continuous duty flow rates [gpm]

Pump type
CR, CRI, CRN 1s
CR, CRI, CRN 1
CR, CRI, CRN 3
CR, CRI, CRN 5
CR, CRI, CRN 10
CR, CRI, CRN 15
CR, CRI, CRN 20
CR, CRN 32
CR, CRN 45
CR, CRN 64
CRT 2
CRT 4
CRT 8
CRT 16
®
* Grundfos Cool-Top is only available in the following pump types:
Pump type
Standard (CR)
I version (CRI)
N version (CRN)

8.11 Check valves

A check valve may be required on the outlet side of the pump to
prevent the pump inlet pressure from being exceeded.
When a pump with no check valve is stopped because there is no
demand on the system (all valves are closed), the high system
pressure on the outlet side of the pump will "find" its way back to
the inlet of the pump.
This is especially critical for CRN-SF applications because of the
very high outlet pressures involved. As a result, most CRN-SF
installations require a check valve on the outlet piping.
min. °F to 176 °F
(min. °C to 80 °C)
0.5
0.9
1.6
3.0
5.5
9.5
11
14
22
34
1.3
3.0
4.0
8.0
CR 1s CR 1 CR 3
● ● ●
● ● ●
at 210 °F at 248 °F
(at 99 °C) (at 120 °C)
0.7 1.2
1.3 2.3
2.4 4.0
4.5 7.5
8.3 14
14 24
17 28
21 35
33 55
51 85
2.0 3.3
4.5 7.5
6.0 10
12 20
CR 5 CR 10 CR 15
● ● ●
● ● ●
at 356 °F
(at 180 °C)
1.2*
2.3*
4.0*
7.5*
14*
24*
28*
35*
55*
85*
N/A
N/A
N/A
N/A
CR 20 CR 32 CR 45 CR 64
● ●
●
● ● ●
●
●
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