Balancing The Oxygen Sensor - Viessmann Vitoflex 300-RF series Service And Maintenance Instructions

Vitoflex 300-RF Service & Maintenance

Balancing the Oxygen Sensor

The oxygen sensor is subject to ageing which can be compensated by a oxygen sensor compensation.
The oxygen sensor compensation is necessary if the residual oxygen to fresh air is <20%.
Balancing the oxygen sensor
Remove and clean
the oxygen sensor
Measure the oxygen
sensor signal
Boiler status "off"
Balance the oxygen sensor
Install the oxygen sensor
CAUTION
The oxygen sensor is constantly heated and is very hot.

Clean the oxygen sensor using a wire brush

Hold the oxygen sensor downwards and gently
tap out with a wire brush until no more dirt falls
out of the sensor

Let the oxygen sensor hang freely in the air
without contact to metal

The oxygen sensor must be supplied with a
heating voltage in the range between 13.0 and
13.8V (measured at the white/white wires)

The heating voltage can be adjusted on the main
board

The signal voltage must be in the range between
-6 and -11 mV (measured at the grey-/black+wires)

The boiler status must be "off" and the exhaust
gas temperature must be <122°F (50°C)

The oxygen sensor must be supplied with current
for min. 5 minutes

Carry out the oxygen sensor balancing in the
operating console
Press OK+F3 (simultaneously)parametercontrol
menu option 68

Wait for the confirmation"Active"

Install the oxygen sensor so it is leak tight

Check again with the flue
Troubleshooting
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