Legend:
1 Flue gas non-return valve
2 Modulating Fan
3 Gas valve
4 Ionization and ignition electrode
5 Primary heat exchanger
6 BoilerowsensorNTC1
7 Boiler return sensor NTC2
8 Water pressure sensor P1
9 High-eciencypump
10 Siphon
11 Heater dirt trap
12 3-way valve
13 Automatic ventilator
14 3 bar safety valve
15 Reserve tank heat exchanger for
warm water
16 Warm water sensor NTC3
17 Mixing valve thermostat
18 Flow-through limiter
g Gas connection
v Boilerowconnection
r Boiler return connection
c Condensate drain
a Expansion vessel connection (C 34)
k Cold water connection
w Warm water connection
Illustration: THISION S PLUS Combi 34