Viessmann Vitovalor PT2 Installation And Service Instructions For Contractors page 141

Repairs
(cont.)
Fig. 93
20
10
8
6
4
2
1
0.8
0.6
0.4
10 30 50 70 90 110
Temperature in °C
Fig. 94 Sensor type: NTC 10 k
1. Check the leads from the flue gas temperature
sensor.
2. Disconnect the leads from the flue gas temperature
sensor.
Fault during commissioning (fault message F.416)
During commissioning, the control unit checks for cor-
rect placement of the flue gas temperature sensor. If
fault message F.416 is displayed:
Ω
3. Rotate sensor (anti-clockwise) by
it (bayonet fitting).
4. Check the sensor resistance and compare it to the
curve.
5. In the event of severe deviation replace the sensor.
6. Rotate sensor (clockwise) by
Danger
Escaping flue gas can cause poisoning.
When restarting, check for leaks on the flue
gas side.
7. If the permissible flue gas temperature has been
exceeded, the flue gas temperature sensor locks
out the appliance. Reset the burner on the pro-
gramming unit once the flue system has cooled
down.
1. Check whether the flue gas temperature sensor is
correctly installed (bayonet fitting). See previous
diagram.
2. If required, correct the position of the flue gas tem-
perature sensor.
Troubleshooting
turn to remove
¼
turn to install it.
¼
141