Unigas G400A - Attention! if it is necessary to change the head position; CAUTION: perform these adjustments once the burner is turned off and cooled.

PART III: OPERATION
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Only if necessary, change the combusiton head position: to let the burner operate at a lower output, loose the VB screw and move pro-
gressively back the combustion head towards the MIN position, by turning clockwise the VRT ring nut. Fasten VB screw when the
adjustment is accomplished.
Attention! if it is necessary to change the head position, repeat the air and fuel adjustments described above.
CAUTION: perform these adjustments once the burner is turned off and cooled.
VRT
VB
“MAX” head position
”MIN” head position