Burnham 1100-H4 manual Gas Piping

V. Gas Piping

	3. Length of piping and number of fittings. Refer to
WARNING
	Table 7 for maximum capacity of Schedule 40 pipe.
	Table 8 lists equivalent pipe length for standard
Failure to properly pipe gas supply to boiler may
	fittings.
result in improper operation and damage to the	4. Corrections for the specific gravity of natural gas
boiler or structure. Always assure gas piping is
	can be found in Table 6.
absolutely leak free and of the proper size and
	For materials or conditions other than those listed
type for the connected load.
An additional gas pressure regulator may be	above, refer to National Fuel Gas Code, NFPA54/ANSI
	Z223.1, or size system using standard engineering
needed. Consult gas supplier.
	methods acceptable to authority having jurisdiction.
A. Size gas piping. Design system to provide adequate gas
	Table 6: Specific Gravity Correction
supply to boiler. Consider these factors:
		Factors for natural gas
1. Allowable pressure drop from point of delivery to
boiler. Maximum allowable system pressure is ½	Specific		Correction	Specific	Correction
psig. Actual point of delivery pressure may be less;	Gravity		Factor	Gravity	Factor
contact gas supplier for additional information.	---		---	0.85	0.81
Minimum gas valve inlet pressure is stamped on
	---		---	0.90	0.82
the rating label located in the boiler’s vestibule
	0.60		1.00	1.00	0.78
compartment.
	0.65		0.96	1.10	0.74
2. Maximum gas demand. Refer to the boiler’s input
	0.70		0.93	1.20	0.71
as printed on it’s rating label. Also consider existing
	0.75		0.90	1.30	0.68
and expected future gas utilization equipment (i.e.
water heater, cooking equipment).	0.80		0.87	1.40	0.66

Table 5: Gas Ratings

Boiler	Natural/LP	Minimum Natural	Minimum LP	Natural	LP
Model	Maximum	Gas Pressure	Gas Pressure	Manifold	Manifold
Number	Gas Pressure	(in. w.c.)	(in. w.c.)	Pressure	Pressure
	(in. w.c.)	Inlet to Gas Valve	Inlet to Gas Valve	(in. w.c.)	(in. w.c.)
SCG-3
SCG-4
SCG-5
SCG-6	14	4.5	11.5	3.5	10.5
SCG-7
SCG-8
SCG-9

NOTICE

SCG boilers built for altitudes greater than 4,999 feet above sea level need to be specially orificed to adjust for changes in atmospheric conditions. The SCG boiler “H” Model has been certified to operate in atmospheric conditions from 5,000 to 10,000 feet above sea level. Input is de-rated by 10% for applications at 5,000 feet above sea level, and 20% for applications at 10,000 feet above sea levels. De-rate is based on 2% reduction per 1000 feet.

The SCG boiler is available in two (2) altitude Models: The “S” Model 0 to 4,999 feet above sea level, and the “H” Model 5,000 to 10,000 feet above sea level.

For applications above 10,000 feet, consult the manufacturer.

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