Viessmann VITOTRONIC 200 Service Instructions Manual page 175

Controller and sensor PCB
Plug Sensor
F20 Boiler temperature sensor, external heat source
(X6.8/X6.9) (connection on site)
F21 Collector temperature sensor (with integral solar control
function)
(connection on site)
Curves, temperature sensors
Ni 500
640
600
560
520
480
440
400
-40 -20 0
Temperature in °C
(cont.)
40
20 60
PCBs and connection options
Pt 500
860
780
700
620
540
460
-20 20 60
Temperature in °C
Type
Pt500
(PTC)
Pt500
(PTC)
100 140 180
175