4.4 Installing the mounting frame ...........................20
4.5 Positioning the boiler .........................................21
4.6 Hydraulic connections .......................................22
4.6.1 Flushing the system ..............................................22
4.6.2 Connection of the heating circuit ...........................22
4.6.3 Hydraulic connection of the water circuit for domestic
use ........................................................................23
4.6.4 Connecting the expansion vessel .........................23
4.6.5 Connecting the condensate discharge pipe ..........24
4.6.6 Filling the siphon ...................................................24
4.7 Gas connection ...................................................25
4.8 Flue gas system connections ............................26
4.8.1 Classification .........................................................26
4.8.2 Lengths of the air/flue gas pipes ...........................27
4.9 Installing the outside sensor .............................28
4.9.1 Choice of the location ............................................28
4.9.2 Installing the outside sensor ..................................28
4.10 Electrical connections ........................................29
4.10.1 Control unit ............................................................29
4.10.2 Recommendations ................................................30
4.10.3 Position of the PCBs .............................................31
4.10.4 Accessing the connection terminal blocks ............32
4.10.5 Connecting a direct heating circuit ........................34
4.10.6 Connecting a direct heating circuit and a domestic hot
water tank ..............................................................35
4.10.7 Connecting two circuits and a domestic hot water tank
before the mixing tank ...........................................37
4.10.8 Connecting two circuits and a domestic hot water tank
after the mixing tank ..............................................39
4.10.9 Hot water storage tank connection ........................41
4.10.10 Pool connection .....................................................46
4.10.11 Connecting a mixed tank .......................................48
4.10.12 Connecting the options .........................................49
4.10.13 Connection in cascade ..........................................50
4.11 Electrical diagram ...............................................53
4.12 Filling the system ...............................................54
4.12.1 Water treatment ....................................................54
4.12.2 Filling the system ..................................................56
5 Start-up ......................................................................................................57
5.1 Control panel .......................................................57
5.1.1 Description of the keys ..........................................57
5.1.2 Description of the display ......................................58
5.1.3 Access to the various browsing levels ..................60
5.1.4 Browsing in the menus ..........................................62
5.2 Check points before commissioning ................63
5.2.1 Preparing the boiler for commissioning .................63
MCA 15 - MCA 25 MCA 25/28 MI Contents
29/04/2010 - 300022146-001-B 2
