Operating Conditions; General Recommendations - Grundfos MAGNA3 Manual

5

5. Operating conditions

General recommendations

Water in heating
systems
Domestic hot water
Water containing glycol
Liquid temperature
Application
General
Domestic hot-water systems
Location
The pump is designed for indoor installation.
Always install the pump in an dry environment where it
will not be exposed to drops or splashes, for example
water, from surrounding equipment or structures.
As the pump contains stainless-steel parts, it is
important that it is not installed directly in
environments, such as:
• Indoor swimming pools where the pump would be
exposed to the ambient environment of the pool.
• Locations with direct and continuous exposure to a
marine atmosphere.
• In rooms where hydrochloric acid (HCl) can form
acidic aerosols escaping from, for example, open
tanks or frequently opened or vented containers.
The above applications do not disqualify for installation
of MAGNA3. However, it is important that the pump is
not installed directly in these environments.
Ambient conditions
Ambient conditions
Ambient temperature during
operation
Ambient temperature during
storage and transport
Relative humidity
32
Water quality according to local standards
such as the German standard VDI 2035
Degree of hardness up to 14 °dH
Maximum viscosity = 10-50 cSt ~ 50 %
water and 50 % ethylene glycol at +14 °F
(-10 °C)
Temperature range
+14 to +230 °F (-10 to +110 °C)
Up to 149 °F (65 °C) recommended
32 to 104 °F (0 to 40 °C)
-40 to 158 °F (-40 to +70 °C)
Maximum 95 %
Maximum operating pressure
PN 12: 175 psi (12 bar, 1.2 MPa).
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.
Liquid temperature
MAGNA3
[167 °F (75 °C)] [203 °F (95 °C)] [230 °F (110 °C)]
DN
Inlet pressure [psi (bar)]
32-60/100 1.5 (0.10)
40-80/120/180 1.45 (0.10)
50-80 1.45 (0.10)
50-150 10.15 (0.70)
65-120/150 10.15 (0.70)
80-100 7.25 (0.50)
100-120 10.15 (0.70)
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).
MAGNA3
5.0 (0.35) 14.5 (1.0)
7.25 (0.50) 14.50 (1.00)
5.80 (0.40) 14.50 (1.00)
17.40 (1.20) 24.66 (1.70)
17.40 (1.20) 24.66 (1.70)
14.50 (1.00) 21.76 (1.50)
17.40 (1.20) 24.66 (1.70)