GAS CONNECTION
The system must be equipped with all the accessories required by current regulations.
We recommend the following:
always include a filter, do not apply mechanical strain to the components and, therefo-
re install a flexible joint as well as a pressure stabilizer and an interception cock at the
heating system inlet. The pipes must be laid using rigid pipes. Any flexible pipes must
be type approved.
Also bear in mind the necessary space required for carrying out maintenance opera-
tions on the burner and the boiler. After fitting the valve unit on the burner, check that
there are no gas leaks during the first ignition stage.
ADJUSTMENTS
AIR ADJUSTMENT (EM 12-E / EM 18-E)
The easily accessible micrometric screw device (A) al-
lows fine, stable, precise adjustment of delivery air. After
loosening the crown (B) turn the screw clockwise to re-
duce throttle valve aperture: turn anticlockwise to incre-
ase it.
GEARED MOTOR CONTROLLING AIR DELIVERY (EM 18/2-E)
The geared motor limit switch and auxiliary contacts are triggered by easily accessible
adjustable cams, which can be set against o graduated scale.
SETTING THE CONTACT TRIGGERING POINT
General information:
CAM V (2nd stage) - Cam controlling air valve fully open position (maz. firing rate with
both stages in operation).
CAM IV (1nd stage) - Cam controlling minimum air flow condition (min. firing rate 1st
stage only in operation).
CAM II-III (MV1-MV2) - Auxiliari cam activating the 2nd stage valve.
RECOMMENDATIONS TO PROPERLY SET THE GEARED MOTOR
The geared motor is set upon testing as follows:
CAM V (2nd stage) : is set on approx 100°-110°
CAM IV (1nd stage) : is set on approx 35°÷45°.
CAM II-III (MV1-MV2): is set in such a way that the 2nd stage valve opens when the air
shut-off valve is at 80°÷90°.
Changes to this calibration during installation are legible even when the burner is in
operation by acting on the adjusting screws of the cams.
Tightening the screws increases the angle and positioning of the cams.
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