7
CF2500/CF3500
Burner Manual
Table 2 - Air Tube Capacity Versus Firebox Pressure
Maximum Firing Rate GPH
Model
Tube
Firebox
Pressure
(In W.C.)
No
Reserve
Air
10% Turndown
(GPH)
CF2500 &
CF2500A
KP
0.0
25.0
22.5
0.2
24.8
22.3
0.4
24.6
22.3
0.6
24.5
22.1
0.8
24.3
21.9
1.0
24.1
21.7
CF3500A
KM/
KR
0.0
35.0
31.5
0.2
33.5
30.2
0.4
32.0
28.8
0.6
30.2
27.2
0.8
28.8
25.9
1.0
27.1
24.4
Note:
10% turndown indicates suf
fi
cient reserve air to reduce
the CO
2
in the
fl
ue to 90% of its value.
Note:
The above ratings may vary 5% due to variations in
actual job conditions.
Dust and Moisture
Mount the Burner
Mount Flange(s) on Air Tube
This section does not apply to burners with welded
fl
anges.
Do not install air tube on burner.
For non-pressure
fi
ring
fl
ange, refer to
Figure 4
:
Install gasket (item
a
) and
fl
ange (item
c
). Ignore the
next paragraph.
For pressure-
fi
ring
fl
ange, refer to
Figure 4
: Slide
gasket (item
a
) onto the air tube, making sure the
top of the air tube is up. Predrill holes in the pressure
fi
ring plate (item
b
) to match the appliance studs.
Slide the pressure
fi
ring plate (item
b
) and
fl
ange
(item
c
) onto the air tube as shown. Wrap ceramic
fi
ber rope (not shown) around the air tube and press
tightly into the inside diameter of the
fl
ange (item
c
).
Slide the air tube (item
d
) into position in the
appliance front. Tighten the
fl
ange-mounting-stud
nuts. Set the insertion of the air tube so dimension
G
is
1/4”
nominal.
Pitch the air tube at 2° from horizontal as shown and
secure the
fl
ange to the air tube.
○
○
○
○
○
Figure 4 – Mount Flange(s) on Air Tube
Stray Light
Protect Against Stray Light
Lockout. Failure to follow
these instructions could cause loss of burner
operation resulting in no heat, an unplanned
process interruption, work stoppage and the
potential for frozen plumbing or other cold
weather property damage.
The control must detect a dark, no-
fl
ame condition
in order to start the burner or it will hold in the stray
light lockout mode.
Shield the burner view window from direct exposure
to intense light.
○
○
Protect Against Dust and
Moisture
Wet, dusty environments could lead to blocked air
passages, corrosion damage to components, impaired
combustion performance and result in asphyxiation,
explosion or
fi
re.
This burner is designed for clean, dry installations.
Electrical controls are not protected against rain or sprayed
water.
Keep the installation clear of dust, dirt, corrosive vapors,
and moisture.
Protective covers and more frequent maintenance may be
required.
y
y
y
y
Section: Mount the Burner
Protect the Air Tube From
Overheating
Overheating could cause damage to the air tube and
other combustion components leading to equipment
malfunction and impaired combustion performance.
The end of the air tube must not extend into the
combustion chamber unprotected unless it has
been factory-tested and speci
fi
ed by the appliance
manufacturer.
Position the end of the air tube 1/4” back from
fl
ush with the refractory inside entry wall to prevent
damage from overheating.
y
y
