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4.17
FLUE GAS ANALYSIS
To perform complete flue gas analysis, follow the instructions below.
SOME IMPORTANT WARNINGS TO CONSIDER DURING THE
COMBUSTION ANALYSIS ARE LISTED BELOW:
FOR A CORRECT ANALYSIS NO AIR MUST FLOW INTO THE
PIPE FROM OUTSIDE DUE TO A BAD TIGHTENING OF THE
CONE OR A LEAK IN THE PIPELINE.
THE FUMES PIPE MUST BE CHECKED IN ORDER TO AVOID ANY
LEAKAGES OR OBSTRUCTIONS ALONG THE PATH.
THE CONNECTORS OF THE FUMES PROBE AND OF THE CONDENSATE
FILTER MUST BE WELL CONNECTED TO THE INSTRUMENT.
KEEP THE CONDENSATE TRAP IN THE VERTICAL POSITION DURING
THE ANALYSIS; A WRONG POSITIONING MAY CAUSE CONDENSATE
INFILTRATIONS IN THE INSTRUMENT AND THUS DAMAGE THE
SENSORS.
DO NOT PERFORM ANY MEASUREMENT WHEN THE FILTER IS
REMOVED OR DIRTY IN ORDER TO AVOID ANY RISK OF IRREVERSIBLE
DAMAGES ON SENSORS.
4.17.1 Switching on the instrument and auto-calibration
Press the On/Off key to switch on the instrument - an introductory screen will appear. After a couple of moments
the instrument will zero itself and will state that the sample probe should not be inserted in the stack.
In case the instrument is equipped with the electrovalve for automatic auto-zeroing, it will ask for the insertion of
the gas probe in the stack. On the other hand if the instrument has not the electrovalve, it will require not to
insert the gas probe in the stack. In the latter it is important that the sample probe is not inside the stack since,
during auto-calibration, the instrument draws fresh air from the environment and detects the zero value of the
O
, CO and NO sensors, the details of which are then memorised and used for reference during the analysis. It
2
is equally important that this phase is performed in a fresh-air environment.
The pressure sensor is also zeroed during auto-calibration.
4.17.2 Inserting the probe inside the stack
When auto-calibration is complete the instrument will
instruct the user to insert the sample probe that has
been previously connected to the relative input on the
instrument, and the analysis screen will appear
automatically.
In order for the probe to be inserted at the right point
within the stack, its distance from the boiler has to be
twice the diameter of the stack pipe itself or, if this is
not
possible,
must
manufacturer's instructions.
In order to position the probe correctly, a reliable
support must be provided by drilling a 13/16 mm hole
in the manifold (unless already present) and screwing
in the positioning cone provided with the probe - in this
way no air is drawn from the outside during sampling.
The screw on the cone allows the probe to be stopped at the right measuring depth - this usually corresponds to
the centre of the exhaust pipe. For greater positioning accuracy, the user may insert the probe gradually into the
pipe until the highest temperature is read. The exhaust pipe must be inspected before carrying out the test, so
as to ensure that no constrictions or losses are present in the piping or stack.
4.17.3 Flue Gas Analysis
After the sample probe has been inserted in the stack and the combustion air temperature probe (if used) has
been inserted in the relative sample manifold, if the instrument has not been configured during auto-calibration,
K900000000SE 022628A0 071013
comply
with
the
boiler
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