68
1
2
3
4
5
7
8
6
9
10
11
Fig. 3/a
“25 - 30 BF” models
KEY
1 Control panel
2 Circulation pump
3 Air relief valve
4 Burners
5 Expansion vessel
6 C.H. sensor (SM1/SM2)
7 Air pressure switch
8 Fan
9 Primary exchanger
10 Ignition/detection electrode
11 Gas valve