Submittal Sheet

Operating conditions
MAGNA3
5
35
Minimum inlet pressure
The following relative minimum pressure must be
available at the pump inlet during operation to avoid
cavitation noise and damage to the pump bearings.
The values in the table below apply to single-head
pumps and twin-head pumps in single-head operation.
Note: Not all variants are available in all markets.
In the case of cascade twin-head operation, increase
the required relative inlet pressure by 1.45 psi (0.1 bar,
0.01 MPa) compared to the stated values for
single-head pumps or twin-head pumps in single-head
operation.
Note: The actual inlet pressure plus pump pressure
against a closed valve must be lower than the
maximum permissible system pressure.
The relative minimum inlet pressures apply to pumps
installed up to 984 ft (300 meters) above sea level. For
altitudes above 984 ft (300 meters), increase the
required relative inlet pressure by 0.145 psi (0.01 bar,
0.001 MPa) per 328 ft (100 meters) altitude. The
MAGNA3 pump is only approved for an altitude of
6560 ft (2000 meters).
Closed valve operation
MAGNA3 pumps can operate at any speed against a
closed valve for several days without damage to the
pump. However, Grundfos recommends you to operate
at the lowest possible speed curve to minimise energy
losses. There are no minimum flow requirements.
Note: Do not close inlet and outlet valves
simultaneously, always keep one valve open when the
pump is running to avoid pressure buildup. Media and
ambient temperatures must never exceed the specified
temperature range.
Pumped liquids
The pump is suitable for thin, clean, non-aggressive
and non-explosive liquids, not containing solid
particles or fibers that may attack the pump
mechanically or chemically. In heating and cooling
systems, the water must meet the requirements of
accepted standards, codes, and any authority having
jurisdiction (AHJ) requirements.
In domestic hot-water systems, we recommend that
you use MAGNA3 pumps only for water with a degree
of hardness lower than approximately 14 °dH.
In domestic hot-water systems, we recommend that
you keep the liquid temperature below 149 °F (65 °C)
to eliminate the risk of lime precipitation.
You can use MAGNA3 pumps for pumping water and
glycol mixtures up to 50 %.
Example of a water and ethylene glycol mixture:
Maximum viscosity: 10-50 cSt ~ 50 % water and 50 %
ethylene glycol mixture at +14 °F (10 °C).
The pump is controlled by a power-limiting function
that protects against overload.
The pumping of glycol mixtures will affect the
maximum curve and reduce the performance,
depending on the water and ethylene glycol mixture
and the liquid temperature.
To prevent the ethylene glycol mixture from degrading,
avoid temperatures exceeding the rated liquid
temperature and minimize the operating time at high
temperatures.
You must clean and flush the system before the
ethylene glycol mixture is added.
To prevent corrosion or lime precipitation, maintain the
ethylene glycol mixture regularly. If further dilution of
the supplied ethylene glycol is required, follow the
glycol supplier's instructions.
MAGNA3
Liquid temperature
167 °F
(75 °C)
203 °F
(95 °C)
230 °F
(110 °C)
Inlet pressure
[psi (bar)]
25-40/60/80/100/120 1.5 (0.10) 5 (0.35) 14.5 (1.0)
32-40/60/80/100/120 1.5 (0.10) 5 (0.35) 14.5 (1.0)
32-40/60/80/100/120 F 1.5 (0.10) 5 (0.35) 14.5 (1.0)
32-120 F 1.5 (0.10) 2.9 (0.2) 10.15 (0.7)
40-40/60 F 1.5 (0.10) 5 (0.35) 14.5 (1)
40-80/100/120/150/180 F 1.5 (0.10) 7.25 (0.5) 14.5 (1)
50-40/60/80 F 1.5 (0.10) 5.8 (0.4) 14.5 (1)
50-100/120 F 1.5 (0.10) 7.25 (0.5) 14.5 (1)
50-150/180 F 10.15 (0.70) 17.4 (1.2) 24.66 (1.7)
65-40/60/80/100/120/150 F 10.15 (0.70) 17.4 (1.2) 24.66 (1.7)
80-40/60/80/100/120 F 7.25 (0.50) 14.5 (1.0) 21.76 (1.5)
100-40/60/80/100/120 F 10.15 (0.70) 17.4 (1.20) 24.66 (1.7)