Beckett CF 2500/ 3500 - Manual (Page 5)

Instruction Manual – Model CF2500/CF3500 Oil Burner
5
Form 6104 BCF-35-R0699
3502
E
D
G
F
T
2° 1
Table 2 – Air tube capacity vs. firebox pressure
Figure 2 – Air tube mounting dimensions
E Insertion depth
G Air tube to inside of chamber
– 0.25" ± 0.125"
T Air tube length
D Tube diameter
Figure 1 – Min. combustion chamber dimensions
① Install the burner with a 2° pitch as shown.
❏
Verify firing rate
• Refer to appliance manufacturer’s instructions (if avail-
able) for firing rate and nozzle selection. Otherwise, the
maximum recommended firing rate for the burner depends
on the length of the firing chamber and the distance from
the burner center to the chamber floor. Verify that the cham-
ber dimensions are at least as large as the minimum values
given in
Figure 1 . If the appliance dimensions are smaller
than recommended, reduce the firing rate accordingly.
❏
Verify air tube
• The information in this section may be disregarded if the
air tube is supplied by the appliance manufacturer.
• The following tube arrangements are available:
Model CF2500A : Tube KP — 17.0 to 19.9 GPH
Model CF2500 : Tube KP — 17.0 to 25.0 GPH
Model CF3500A : Tube KM — 17.0 to 35.0 GPH or
Tube KR — 17.0 to 35.0 GPH
• Maximum firing capacity depends on the firebox pressure.
Use Table 2 to verify the correct air tube type for the firing
rate required. (Tube KR [ CF3500A ] is an optional air tube
combination for maximum capacity rate. It requires a larger
I.D. flange No. 51631.)
• See Figure 2 to verify the correct air tube length and air
tube combination code.
3501
A
L
Firing rate
Minimum dimensions
(all boilers)
A L
17 gph 10.5" 48.0"
22 gph 11.5" 58.0"
27 gph 12.5" 66.0"
32 gph 12.5" 73.0"
35 gph 13.0" 77.0"
A.T.C. Codes
(A.T.C. = Air Tube Combination)
CF2500A/
CF2500
CF3500A
Tube KP Tube KM Tube KR
Dimensions Dimensions Dimensions
T D F T D F T D F
All — 6 ½" 3¼" All — 8" 4 ½" All — 9 ¹⁵⁄₁₆ " 5 ¹⁄₈ "
6¾" CF 66 KP 8" CF 80 KM — —
— — 9 ¼" CF 92 KM — —
10¼" CF 102 KP 11 ½" CF 114 KM 11 ½" CF 114 KR
13¾" CF 136 KP 15" CF 150 KM 14" CF 140 KR
17¾" CF 176 KP 19" CF 190 KM 19" CF 190 KR
Firebox
pressure
(In. W.C.)
Tube KP Tube KM/KR
No
reserve
air
10%
turndown
No
reserve
air
10%
turndown
Maximum firing rate GPH
0.0 25.0 22.5 35.0 31.5
0.2 24.8 22.3 33.5 30.2
0.4 24.6 22.3 32.0 28.8
0.6 24.5 22.1 30.2 27.2
0.8 24.3 21.9 28.8 25.9
1.0 24.1 21.7 27.1 24.4
Note: 10% turndown indicates sufficient reserve air to reduce
the CO
2
in the flue to 90% of its value.
Note: The above ratings may vary 5% due to variations in actual job
conditions.