Insulating Shells; Non-Return Valve - Grundfos MAGNA3 25-80 Installation And Operating Instructions Manual

6.8 Insulating shells

Insulating shells are available for single-head pumps only.
Limit the heat loss from the pump housing and
pipes.
Reduce the heat loss by insulating the pump housing and the
pipes. See figs 22 and 10.
• Insulating shells for pumps in heating systems are supplied
with the pump.
• Insulating shells for pumps in air-conditioning and cooling
systems, down to -10 °C, must be ordered separately. See
section 11.7 Insulating kits for air-conditioning and cooling
systems.
The fitting of insulating shells increases the pump dimensions.
Fig. 22 Insulating shells
Pumps for heating systems are factory-fitted with insulating
shells. Remove the insulating shells before installing the pump.

6.9 Non-return valve

If a non-return valve is fitted in the pipe system, make sure that
the set minimum outlet pressure of the pump is always higher
than the closing pressure of the valve. See fig. 23. This is
especially important in proportional-pressure control mode with
reduced head at low flow.
Fig. 23 Non-return valve
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