Beckett CF 2500/ 3500 instruction manual Verify firing rate, Verify air tube, C. Codes

Instruction Manual – Model CF2500/CF3500 Oil Burner

❏Verify firing rate

Figure 2 – Air tube mounting dimensions

•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

	T
G	2°
D

EInsertion depth

GAir tube to inside of chamber

– 0.25" ± 0.125"

1T Air tube length

DTube diameter

•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.

Figure 1 – Min. combustion chamber dimensions

L

A

3501

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"

F

E 3502

①Install the burner with a 2° pitch as shown.

A.T.C. Codes

(A.T.C. = Air Tube Combination)

CF2500A/					CF3500A
CF2500
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

Table 2 – Air tube capacity vs. firebox pressure

	Tube KP			Tube KM/KR
Firebox	No		10%	No	10%
pressure	reserve			reserve
			turndown		turndown
(In. W.C.)	air			air
		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 CO2 in the flue to 90% of its value.

Note: The above ratings may vary 5% due to variations in actual job conditions.

Form 6104 BCF-35-R0699 5