1 Air duct
2 Fan
3 Main heat exchanger
4 Temperature sensor (NTC I)
5 Flame sensing electrodes
6 Modulating burner
7 Fully modulating automatic gas
value
8 This control has no function on
this boiler
9 Maximum radiator temperature
control
10 Automatic bypass valve
11 CH flow service valve
12 Gas service valve
13 CH return service valve
14 Pressure relief valve
15 Main on/off control
16 Pressure gauge
17 Display
18 Expansion vessel
19 Expansion vessel charging valve
20 Circulating pump
21 Automatic air vent
22 Ignition electrode
23 Temperature sensor (NTC II)
24 Air pressure switch
25 Flue gas duct
Fig. B.4: Functional Diagram THERMOcompact
Euro B/S_VC_079/0
THERMOcompact