Wayne P250AF-DI, P265-EP Combustion Chambers, Installation of Burner and Controls, PER Hour

COMBUSTION CHAMBERS

The combustion chamber sizes given in Figure 5 are based on the maximum rated BTU capacity. If the input is to be permanently set at a reduced rate, the combustion chamber floor area can be reduced proportionately to the proposed input, allowing 200,000 BTU (211000kJ) per square foot (.093m2) of combustion chamber floor area and proportioning the length about 70% greater than the width.

The height of the walls of the combustion chamber is generally determined by the grate line. The side and front walls should be built about 2” (50.8mm) above the grate line, covering the grate lugs and covering the bases of the water legs of boilers about 3” (76.2mm) or 4” (101.6mm) to avoid heating sections that may be filled with sediment. The back wall should be carried one or two courses higher and overhung to deflect hot gases from direct impingement on the rear heat exchanger surfaces. Hard firebrick should be used for the overhung section to prevent erosion of the brick at this point by the high velocity gases m9moving over it.

The remaining open spaces between the combustion chamber and ash pit walls should be filled with loose insulation. Since this insulation may not stand combustion chamber temperatures, the top course of the combustion chamber walls be laid flat, extending to, and fitting the contour of the firebox and covering the loose insulation.

Always use cement furnished by the brick manufacturer for cementing insulating firebrick. It should be thinned to the consistency of a very thick cream so that the brick can be dipped into it and set in place. The use of other cement or mortar may impair the insulating and radiating qualities of the brick.

Magnesia block insulation, common brick, hard fire brick, dry sand and/or expanded mica products such a “Vermiculite” or “Zonolite” can be used to back up the insulating firebrick. High temperature furnace cement can be used to seal the openings around the burner and furnace.

Approved insulating bricks are: Babcock & Wilcox No. K-23 and No. K-26, A. P. Grenn No. G-23 and No. G-26, Armstrong Cork No. A-23 and No. A-26 an Johns Manville No. JM-23 and No. JM-26.

INSTALLATION OF BURNER AND CONTROLS

The inshot power gas burner was designed especially for converting gun fired oil designed furnaces and boilers. Due consideration was given to making it as simple and easy to install and service as possible without weakening its durability or efficiency. The burner is supplied as a completely assembled package unit.

NOTE: The burner must be installed in such a manner that they unit and all controls will be readily accessible for inspection, cleaning, adjustment and repairs.

SIZING OF INPUT IN RELATION TO FURNACE

FIGURE 140,000 BTUs (147700KJ) per gal. of oil input. For example: Furnace rating 0.60 G.P.H. then 0.60 x 140,000 = 72,000 BTUs input rate

The orifice spud supplied with all burners is the size for the minimum BTU input of the burner for the type gas shown on the rating plate. Figure 6 shows the correct drill size for various inputs.

The correct manifold pressure for natural gas is 3.5” w.c(871.8 Pa). Only minor adjustments in the input rate should be made by adjusting the pressure regulator. The minimum manifold pressure should be 3.0” w.c. (747.2Pa) and the maximum pressure should be 3.5 w.c. (871.8 Pa) the next size larger or smaller orifice size should be used if the desired input rating cannot be obtained within the above manifold pressure adjustment range.

The correct manifold pressure for L.P. gas is 10” w.c. (2491Pa), only minor adjustments in the input rate should be made by adjusting the pressure regulator. The minimum manifold pressure should be 9.5” w.c. (2366 Pa), the maximum pressure 10.0” w.c. (2491 Pa). If the desired input rating cannot be obtained within the above manifold pressure and adjustment range then the next size larger or smaller drill should be used.

B.T.U. (kW)	NATURAL GAS	PROPANE GAS
INPUT	3 1/2” (871.8Pa) W.C.P.	10” (2491 Pa) W.C.P.
PER HOUR	Drill Size	Drill Size
50,000 (14.65)	#30 (3.264mm)	#45 (2.083mm)
75,000 (21.98)	5/32 (3.967mm)	#41 (2.438mm)
90,000 (26.38)	#17 (4.394mm)	#37 (2.642mm)
100,000 (29.31)	#14 (4.623mm)	#35 (2.794mm)
125,000 (36.63)	#5 (5.22mm)	1/8 (3.175mm)
130,000 (38.1)	#4 (5.309mm)	#30 (3.264mm)
150,000 (43.96)	#1 (5.791mm)	#29 (3.454mm)
160,000 (46.89)	15/64 (5.954mm)	#28 (3.569mm)
175,000 (51.29)	C (6.147mm)	#26 (3.734mm)
180,000 (52.75)	1/4 (6.35mm)	#25 (3.797mm)
200,000 (58.61)	G (6.629mm)	#22 (3.988mm)
225,000 (65.94)	J (7.036mm)	#19 (4.216mm)
242,000 (70.92)	L (7.366mm)	#17 (4.394mm)
250,000 (73.27)	M (7.493mm)	#16 (4.496mm)

FIGURE 6

5