Installation manual

14
2.3 Block diagram
29
Legend
1 Flue outlet
2 Main heat exchanger
3 Burner
4 Ignition and control electrode
5 Fan
6 Gas control valve
7 Condensate trap
8 Overheat safety thermostat
9 Heating expansion vessel
10 Heating return thermistor
11 Heating flow thermistor
12 Ignition module
13 Pump
14 Water pressure sensor
15 Domestic plate to plate heat
exchanger (*)
16 Three way valve
17 Drain cock
18 DHW flow sensor (*)
19 Filling system (*)
20 Filter on cold water inlet (*)
21 Heating isolating valve
22 Domestic cold water
isolating valve (*)
23 Heating isolating valve
24 Gas isolating valve
25 Heating safety valve
26 Thermal fuse
27 Silencer
28 Filling tap (*)
29 By-pass
A Heating return
B Cold water inlet (*)
C Heating flow
D Domestic hot water outlet (*)
E Gas
(*) Not required for SB models