HYDRAULIC CIRCUIT
16
15
LEGEND
A
Gas
B
ICold water inlet
Hot water outlet
C
D
System delivery
E
System return
Air bleed valve
1
Control electrode
2
3
Nozzle connection
Ignition transformer
4
Ignition electrodes
5
6
System delivery control sensor
System return control sensor
7
Fan
8
12
1
6
14
D C A B
2
3
21
18
20
11
19
E
17
9
Air pressure switch
10
Gas valve
Water trap for condensate discharge
11
12
Expansion tank
13
Circulating pump
Hot water sensor
14
3-way valve
15
16
Water-heater
Filling cock
17
Safety valve
18
19
Drain tap
Lack of water pressure switch
20
Air bleed tap
21
5
4
8
10
9
7
1
13
47