Bard WG3S1, WG4S1, WG5S1 Natural Gas Orifice and Altitude Tables, Bard Part No, Orifice Diameter

Natural Gas Orifice and Altitude Tables

			6,001 to 8,000 Feet	8,001 to 10,000 Feet
			Requires Pressure Switch	Requires Pressure Switch
Factory	Gas Heat*	Up to 6,000 Feet No	Change and Orifice	Change and Orifice
Standard	Value	Changes Except	Change	Change
Input	BTU/Cu. Ft.	for BTU Content	Based on BTU Content	Based on BTU Content
25000 BTU	700-749	2.90	2.80	2.70
Per Burner
	750-799	2.80	2.70	2.60
	800-849	2.70	2.60	2.50
	850-899	2.60	2.50	2.45
	900-949	2.50	2.45	(2.40)
	950-999	2.45	(2.40)	2.35
	1000-1049**	(2.40)	2.35	[2.30]
	1050-1100	[2.30]	2.25	2.20
	Pressure Switch	Standard (.55)	Order 8620-189 High Altitude Pressure Switch Kit (.42)
(2.40) is the standard factory installed orifice size			[2.30] orifices are shipped with the unit for field installed
			optional 10% derate
			6,001 to 8,000 Feet	8,001 to 10,000 Feet
Optional			Requires Pressure Switch	Requires Pressure Switch
10% Field	Gas Heat*	Up to 6,000 Feet No	Change and Orifice	Change and Orifice
Converted	Value	Changes Except	Change	Change
Derate	BTU/Cu. Ft.	for BTU Content	Based on BTU Content	Based on BTU Content
22500 BTU	700-749	2.75	2.70	2.60
Per Burner
	750-799	2.70	2.60	2.50
	800-849	2.60	2.50
	850-899	2.50	2.45	(2.40)
	900-949	(2.40)	2.35	[2.30]
	950-999	2.35	[2.30]	2.25
	1000-1049**	[2.30]	2.25	2.20
	1050-1100	2.25	2.25	2.20
	Pressure Switch	Standard (.55)	Order 8620-189 High Altitude Pressure Switch Kit (.42)
[2.30] orifices are shipped with the unit for field			(2.40) is the factory installed orifice size for full rated input
installed optional 10% input rate.

*At standard conditions: 30.00 inches Mercury, 60F, saturated, .60 specific gravity.

**All Natural Gas factory orifice sizing and standard input ratings based on nominal 1025 BTU/cu ft gas and sea level conditions

All other orifice sizes shown are available as individual items. See Orifice charts below for part numbers and number required.

Bard Part No.	Orifice Size (mm)	Orifice Diameter
9010-092	2.10	0.0826
9010-088	2.15	0.0846
9010-087	2.20	0.0866
9010-086	2.25	0.0885
9010-082	2.30	0.0905
9010-085	2.35	0.0925
9010-079	2.40	0.0945
9010-084	2.45	0.0964
9010-093	2.50	0.0984
9010-094	2.60	0.1024
9010-095	2.70	0.1063
9010-096	2.75	0.1082
9010-097	2.80	0.1102
9010-098	2.90	0.1142

No. of Orifices Required

Based on Unit Input Rating

45,000 (2)

50,000 (2)

68,000 (3)

75,000 (3)

90,000 (4)

100,000 (4)

113,000 (5)

125,000 (5)

Form No.	S3396-1112
Supersedes	S3396-212
Page	8 of 12