Buhler GAS 222 Series, Installation And Operation Instruction Manual

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Bedienungs- und Installationsanleitung
Installation- and Operation Instruction
Gasentnahmesonden /
sample
gas
probe
Baureihe
/ Series
222.20-HT / 222.20-HT-OW-OR
26 BX460026, 01/2011 Art. Nr. 90 31 181
7.2 Basic functions of the controller for GAS 222.20-HT
After turning the device on, the probe is heated up. At the controller, the display shows the actual
temperature. As long as the preset working range (see section 7.4 for parameter setting) is not reached, the
display blinks and the alarm output is set. If the working range is reached, the alarm output is reset and the
display stops blinking.
The nominal temperature, the working range and the temperature unit (°C/°F) are set with three keys at the
controller. Section 7.4 describes setting the parameters.
Default settings at delivery are: Unit: °C; nominal temperature: 260 °C; working range: ±10 °C
7.3 Maintenance of the filter element
The sample gas tube is equipped with a particulate filter that has to be replaced depending on the amount
of dust and particles.
7.3.1 Replacing the downstream filter for GAS 222.20-HT-OW-OR
 Stop gas flow, if necessary, shut down process.

Press and push slightly the handle on the rear of the probe, turn it by 90° (the handle must be now
in horizontal position) and pull the handle with the filter out.
 Remove the exhausted filter element and check proper conditions of the sealing surfaces.
 Before installing the new filter element always replace the O-ring (included in the delivery) on the
handle plug carefully, put a new filter element onto it and insert the handle into the probe.

If necessary, the sample tube may now be cleaned with a cleaning tool or by purging it with air.
 Push to the very end and turn handle by 90° (handle is vertical now).
NOTE
Ceramic filter elements
are very brittle by nature. Handle them with care, don’t drop them.
Filter elements made out of sintered stainless steel can be cleaned in an ultrasonic bath
and be used several times as long as both seals are still in proper conditions.