Burnham 1100-H4 manual Main Burners and Firebox, Differential Pressure Switch Settings

E.Main Burners and Firebox.

1.Vacuum firebox. Exercise care - do not damage base insulation.

2.Clean main burners. Brush top of burners with soft bristle brush. See Figure 44. Vacuum to remove any dirt and lint.

3.Vacuum tip of pilot burner.

4.Check gas orifices for lint and dirt. Clean as necessary.

5.Install main burners by reversing procedure to remove burners.

a.Pilot burner must be installed in original location. See Table 14.

b.Main burners must be properly secured in burner tray slot at rear of firebox and over gas orifice.

See Figure 44.

c.Pilot gas supply and pilot lead wires must be reconnected.

d.Burner access panel must be securely in place.

e.Reinstall air diffuser screen.

f.Reconnect Flame Roll-out wires.

g.Air Intake Box Front Door must be installed.

F.Check operation. Follow steps G through P from Section VIII: System Start-up.

G.Procedure for Measuring Differential Pressure (See Figure 45).

1.With boiler off, remove Gray and Black Hoses at differential pressure switch.

2.With tees and ¼ inch aluminum stubs, connect water manometer as shown with additional tubing.

3.Start boiler and read Pressure on Manometer when boiler water temperature reaches operating temperature. Refer to Table 15 for minimum readings.

Table 15: Differential Pressure Switch Settings

NOTE: If switch drops-out before boiler reaches temperature or if pressure differential readings are below minimums shown in Table 15, check for cracks in hose or contact your nearest Burnham representative.

4.Stop boiler, remove manometer and reconnect hoses to differential pressure switch. See Figures 42 and 45.

Figure 45: Differential Pressure Measurement

Boiler Model	Minimum Differential Pressure
	Sea Level to 4,999 Ft.	5,000 - 10,000 Ft. Elevation
SCG-3	1.32” w.c.	.80” w.c.
SCG-4	1.17” w.c.	.65” w.c.
SCG-5	1.17” w.c.	.65” w.c.
SCG-6	.88” w.c.	.35” w.c.
SCG-7	.80” w.c.	.30” w.c.
SCG-8	.88” w.c.	.35” w.c.
SCG-9	.88” w.c.	.35” w.c.

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