Immergas MAGIS M4-30 Use And Installation page 70

• Make sure that the components installed in the on-field pipes can withstand the water temperature and pressure.
• The drain cocks must all be installed in the low points of the system to completely drain the circuit during maintenance.
• All the high points of the system must be fitted with vents. The vents must be located in easily accessible points to perform
service operations. There is an automatic air purge valve inside the unit. Check that this air purge valve is not tight so that
air may be automatically relieved from the water circuit.
9.4.2 Water volume and dimensioning of the expansion vessels.
Models 4-16kW.
The units are equipped with an 8L expansion vessel with a default pre-pressure of 1.5 bar. The pre-pressure of the expansion
vessel might need to be adjusted to guarantee proper operation of the unit.
1) Check that the total water volume of the system always available and not shut off, excluding the internal water volume of
the unit, is at least 40L. See Chap. 14 "Technical specifications" to find the total internal water volume of the unit.
NOTE
• In the majority of applications, this minimum water volume will be satisfactory.
• However in critical processes or in environments with a high thermal load, additional water could be necessary.
• When the circulation in each space heating circuit is controlled by remote control valves, this minimum water volume
needs to be maintained even if all the valves are closed.
2) The volume of the expansion vessel must be adjusted to the total volume of the water system.
3) Dimension the expansion for the heating and cooling circuit.
The volume of the expansion vessel can follow the figure below:
25
20
15
10
5
0
0 50 100 150
Volume dell'acqua di sistema (L) Volume of system water (L)
200 250 300
70
350 400