Viessmann VITOLIGNO 300-C Installation And Service Instructions Manual page 136

Maintenance
Sensors
(cont.)
Further sensors
1.20
1.15
1.10
1.05
1.00
0.95
0.90
0.85
-30 -20 -10
Temperature in °C
Fig. 83
1. Pull out corresponding plug.
2. Check the sensor resistance at the plug.
Lambda probe
The Lambda probe measures the residual oxygen con-
tent in the flue gas.
Make of Lambda probe: NTK wideband probe
Checking the Lambda probe
1. Check the Lambda probe for contamination and
damage. See page 87.
2. Check the connecting cable for damage.
Calibrating the Lambda probe
Note
The Lambda probe can only be calibrated manually.
!
Please note
A hot Lambda probe may cause burns
Wear safety gloves.
Requirements:
■ Boiler not in operation
■ Flue gas temperature < 50 °C
1. Disconnect the Lambda probe plug. Remove the
Lambda probe from the flue pipe. Insert the probe
again.
136
0 10 20 30 40 50
3. Compare the result with the actual temperature (for
scanning, see chapter "Diagnosis").
In the case of severe deviation, check sensor
installation and replace the sensor if required.
Notes
■ Do not paint, wax or treat the probe with any other
such substance. Only use special grease recommen-
ded for Lambda probes to grease the threads.
The Lambda probe receives reference air via the
■
connecting cable. For this reason, ensure that the
connection plugs are kept clean and dry and do not
treat them with contact spray, anti-corrosion agents,
etc.
■ Do not solder the connecting cable; it must be crim-
ped, clamped or secured with screws.
2. Check the Lambda probe for contamination and
damage. Clean if necessary.
3. Call up the service menu on the control unit.
Probe heating is activated automatically.
4. Hang the Lambda probe for at least 15 minutes
outside the boiler in the installation room without
any earth contact.
5. Press + simultaneously for approx.
d
å
4 seconds.
6. Press / to select "Service functions".
| ~
Confirm with .
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