36
INS
TALLER
U
SER
M
AINTEN
AN
CE
TECHNI
CI
AN
TECHNI
CAL
D
AT
A
1.29 MAIN COMPONENTS
35
Key (Fig. 35):
1 - Sample points (air A) - (flue gases F)
2 - Sealed chamber
3 - Fan
4 - Flow probe
5 - Combustion chamber
6 - Ignition and detection electrodes
7 - System pressure switch (absolute)
8 - Boiler pump
9 - D.H.W. flow switch
10 - DHW probe
11 - Gas valve
12 - Condensate drain trap
13 - System filling valve
14 - Positive signal pressure point
15 - Negative signal pressure point
16 - Flue pressure switch
17 - Thermofuse
18 - Condensing heat exchanger
19 - Primary heat exchanger
20 - System expansion vessel
21 - Burner
22 - Safety thermostat
23 - Air vent valve
24 - DHW heat exchanger
25 - Motorized 3-way valve
26 - System draining fitting
27 - By-pass
28 - 3 bar safety valve