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11. Maintenance
11.1 Battery replacement
All instruments manufactured after January 2017 have built-in rechargeable battery.
For the older models, which use a 9V alkaline battery of the 6F22 type, the battery is placed
under the cover on the bottom side of the analyzer. Use only alkaline batteries when replacing.
A no. 1 Philips screwdriver is suitable to remove the cover.
11.2 Oxygen sensor replacement
The oxygen sensor has a limited service life. The analyzer automatically checks the
sensor’s condition and, at the end of its life, the message “Oxygen sensor expired” is displayed
upon activating the instrument. In this case the sensor should be replaced as soon as possible,
as the accuracy of measuring the concentration of oxygen can no longer be guaranteed.
If you are not sure whether you are able to replace the sensor correctly, ask your supplier,
vendor or service technician to change it.
To replace the sensor, first remove the battery cover, then unscrew the three screws fastening
the cover of the instrument. Carefully lift the cover, remove the connector from the oxygen
sensor and remove the sensor and the attached aluminum inlet block.
Warning: The cover is connected to the instrument by several cables. When replacing the
sensor, take care not to put excessive tension on the cables or disconnect them. During the
replacement, the cables must remain bent by their own weight and flexibility; their full
tensioning by moving the cover too far from the instrument is not allowed.
Unscrew the old sensor and install the new one in such a way that the o-ring on the sensor
closely attaches to the inlet block. Do not use excessive strength to tight the sensor to avoid
damaging the thread.
Install the inlet block with the sensor in the lower half of the open instrument. The pins of
the block must easily fit into the holes in the body of the instrument. During the installation
Summary of Contents for HE/02
Page 1: ...MANUAL He O2 Analyzer ...
