Viessmann Vitopend 100-W Installation And Service Instructions Manual page 44

Designs
Connection and wiring diagram
T8 Ignition transformer and ioni-
sation
§ Boiler water temperature sen-
sor
$ Outlet temperature sensor
(only gas combi boilers)
% Cylinder temperature sensor
(only gas system boilers)
44
(cont.)
sÖ Internal circulation pump
dG Gas solenoid valve
fJ Temperature limiter
aVL Flow switch
a-Ö/aBL Interlocking of extractors via
external extension H3
aNS Flue gas monitoring sensor
a:Ö Modulation coil