Alpha E-Tec 25R - Page 8

8
3.8 BOILER SCHEMATIC
Fig. 3.2
Alpha E-Tec 15, 20, 25R - Technical Data
1 Gas isolation valve
2 Gas valve
3 Gas injector
4 Condensate trap
5 Venturi positive pressure point (+)
6 Primary flow sensor
7 Drain valve
8 Overheat thermostat
9 Ignition/sensing electrode
10 Air supply pipe
11 Flue temperature sensor and thermal fuse
12 Flue test point (pressure point +)
13 Air test point (pressure point -)
14 Condensing heat exchanger
15 Burner
16 Primary return sensor
17 Venturi
18 Fan
19 Drain valve
Gas
Condensate discharge
Primary
Heating
return
Primary
Heating
flow
1
2
3
4
5
6
7
8
9
10
11
12
17
19
16
18
15
14
13