1-12
The air/gas mixture is properly adjusted when the burner manifold pressure is in accordance with the
applicable table on page 1-7 and the burners display a bright orange-red glow. If a blue flame is
observed, or if there are dark spots on a burner face, the air/gas mixture requires adjustment.
Adjusting Air/Gas Mixture
Non-CE Units and CE Units Built After April 1999
On the side of the blower housing opposite the motor is a plate with one or two locking nuts.
Loosen the nut(s) enough to allow the plate to be moved, then adjust the position of the plate to open
or close the air intake opening until a bright orange-red glow is obtained. Carefully hold the plate in
position and tighten the locking nut(s).
TYPICAL NON-CE BLOWER ASSEMBLY TYPICAL CE BLOWER ASSEMBLY
ON UNITS BUILT AFTER APRIL 1999
Right
Viewing
Port
Left Viewing
Port is Behind
Motor
(NOTE: Blower
shield omitted
for clarity.)