70
EN
1.4
Structure
20
21
17
18
19
2
1
3
4
7
8
6
9
12
14
15
16
13
5
10
11
1
Smoke thermostat
2
Smoke chamber
3
Dual sensor (thermal safety/delivery)
4
Combustion chamber
5
Ignition/detection electrode
6
Diverter valve
7
System filling unit
8
Domestic hot water sensor
9
Control panel
10
Secondary heat exchanger
11
Gas valve
12
Domestic water filter and flow regulator
13
System relief valve
14
Boiler drain
15
System pump
16
Water pressure switch
17
Automatic bleed valve
18
Burner
19
Primary heat exchanger
20
Expansion vessel
21
Smoke outlet
Fig. 3