Immergas MAGIS M4-30 Use And Installation page 38

• Space heating.
All the slave units can work in space heating mode. The operation mode and temperature setpoint are set on the control
panel (2). Due to the variations of the outdoor temperature and of the load required indoors, several outdoor units can
operate at different times.
In cooling mode, SV3 (23.1) and P_c (23.2) remain OFF. P_o (5) remains ON.
In heating mode, when both ZONE1 and ZONE2 are working, P_c (23.2) and P_o (5) remain ON, SV3 (23.1) alternates
between ON and OFF depending on the set Tw2.
In heating mode, when only ZONE1 works, P_o (5) remains ON, SV3 (23.1) and P_c (23.2) remain OFF.
In heating mode, when only ZONE2 works, P_o (5) remains OFF, P_c (23.2) remains ON, SV3 (23.1) alternates between
ON e OFF according to the set Tw2.
• TBH (tank booster heater) control.
The TBH must be set using the dip switches on the main board (refer to Chap. 10.1). The TBH is only controlled by the
master unit. Refer to 8.1 for the specific control of the TBH.
• Solar energy control.
Energy is only controlled by the master unit. Please refer to Chap. 8.1 for the specific control of solar energy.
NOTE
1. A maximum of 6 units can be connected in cascade in a system. One of them is the master unit, the others are slave
units; the master unit and the slave units can be recognised by whether or not they are connected to the control panel
during operation. The unit with control panel is the master unit, the units without control panel are slave units. Only
the master units can operate in DHW mode. During installation, check the diagram of the cascade system and deter-
mine the master unit; before switching on, remove all the control panels of the slave units.
2. SV1, SV2, SV3, P_o, P_c, P_s, T1, T5, Tw2, Tbt1, Tsolar, SL1SL2, TBH and the control panel must only be connected
to the matching terminals on the main board of the master unit. See Chap. 9.3.1 and 9.7.6.
3. The system is equipped with the self-addressing function. After being switched on the first time, the masters unit
assigns the addresses for the slave units. The slave units will maintain the addresses. After being switched back on, the
slave units will still use the prior addresses. It is not necessary to set the addresses of the slave units again.
4. If an Hd error occurs, refer to Chap. 13.4.
5. It is recommended to use the inverted water return system to avoid hydraulic unbalance between each unit in a
cascade system.
CAUTION
1. In a cascade system, the sensor Tbt1 must be connected to the master unit and Tbt1 set as valid on the control panel
(see Chap. 10.5.15). Otherwise none of the slave units will work.
2. If the external circulation pump needs to be connected in series in the system when the head of the internal water
pump is not sufficient, it is recommended to install the external circulation pump after the balance tank.
3. Please make sure that the maximum ignition time interval of all units does not exceed 2 minutes, otherwise the time
for the request and assignment of the addresses will not be reached, which could make it impossible for the slave units
to communicate normally, triggering an Hd error.
4. A maximum of 6 units can be connected in cascade in a system.
5. The outlet pipe of each unit must be installed with a non-return valve.
Volume requirement of the expansion tank.
12-16 kW
cascade system
n = number of outdoor units
Model
4-8 kW
Balance tank (L)
38
≥ 25
≥ 40
≥ 40*n