Unigas IDEA LG550, Manual Of Installation - Use - Maintenance

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PART I: INSTALLATION
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is towards the operator. As far as the reduced output operation, progressively move the combusiton head towards the “MIN” position,
rotating clockwise the
VRT screw (Fig. 33). The ID index shows how much the combustion head moved.
Calibration of air and gas pressure switches
The air pressure switch locks the control box if the air pressure is not the one requested. If it happens, unlock the burner by means of
the control box unlock pushbutton, placed on the burner control panel. The gas pressure switches check the pressure to avoid the
burner operate when the pressure value is not in the requested pressure range.
Calibration of air pressure switch (only for single stage burners)
Calibration is carried out as follows:

Remove the transparent plastic cap.

Once air and gas setting have been accomplished, startup the burner.

While the burner is operating, rotate slowly and clockwise the adjusting ring nut VR , until the burner locks; read the pressure value
on the scale of the pressure switch and set it again to a value reduced by the 15%.

Repeat the start-up cycle and check the burner runs properly.

Refit the transparent plastic cover on the pressure switch.
Calibration of air pressure switch (double-stage, progressive and fully-modulating)
To calibrate the air pressure switch, proceed as follows:

Remove the transparent plastic cap.

Once air and gas setting have been accomplished, startup the burner.

During the pre-purge phase o the operation, turn slowly the adjusting ring nut VR in the clockwise direction until the burner lockout,
then read the value on the pressure switch scale and set it to a value reduced by 15%.

Repeat the ignition cycle of the burner and check it runs properly.

Refit the transparent plastic cover on the pressure switch.
Calibration of low gas pressure switch
As for the gas pressure switch calibration, proceed as follows:

Be sure that the filter is clean.

Remove the transparent plastic cap.
Fig. 34 - Head in “fully-ahead position”
Fig. 35 - Head in “fully-backward position”
VRT
Fig. 33
ID