Intake And Exhaust Pipe Venting Table; Gas Pipe Capacity - Lennox G26 series User Manual

Vent Pipe
Maximum Maximum
Equivalent Length
Feet Meters
15 4.6
20 6.1
25 7.6
30 9.1
40 12.2
50 15.2
55 16.8
60 18.3
70 21.3
80 24.4
90 27.4
100 30.5
110 33.5
120 36.6
130 39.6
MINIMUM PIPE LENGTHS FOR FURNACES
VENTING NOTES One 90_elbow is equivalent to 5 feet (1.5 m) of straight vent pipe.
Two 45_ elbows are equal to one 90_ elbow.
One 45_ elbow is equivalent to 2.5 feet (.75 m) of straight vent pipe.
One foot (305 mm) length of 2 in. (51 mm) diameter pipe is equivalent to 8 feet (2.4 m) of 3 in. (76 mm) diameter pipe.
Intake and Exhaust pipes must be the same diameter.
2 inch x 3 inch (51 mm x 76 mm) adaptor is furnished with -100 and -125 furnaces for exhaust pipe connection.
Exhaust pipe must terminate with 1-1/2 inch (38 mm) diameter pipe for furnaces using1-1/2 (38 mm) or 2 inch (51 mm) diameter pipe runs.
Exhaust pipe must terminate with 2 inch (51 mm) diameter pipe for furnaces using 3 inch (76 mm) diameter pipe runs.
See pages 10 thru 12 for Termination Kits available.
Nominal Nominal Internal Internal
Iron Pipe Size Diameter
−Inches(mm) −Inches(mm)
1/4 .364
(6.35) (9.246)
3/8 .493
(9.53) (12.522)
1/2 .622
(12.7) (17.799)
3/4 .824
(19.05) (20.930)
1 1.049
(25.4) (26.645)
1−1/4 1.380
(31.75) (35.052)
1−1/2 1.610
(38.1) (40.894)
2 2.067
(50.8) (52.502)
2−1/2 2.469
(63.5) (67.713)
3 3.068
(76.2) (77.927)
4 4.026
(101.6) (102.260)
NOTE−Capacity given in cubic feet of gas per hour (kilo liters of gas per hour) and based on 0.60 specific gravity gas.

INTAKE and EXHAUST PIPE VENTING TABLE

50,000 Btuh (14.7 kW) 75,000 Btuh (22.0 kW)
in. mm
1-1/2 38
2 51
2 51
2 51
2 51
2 51
2 51
3 76
3 76
3 76
3 76
3 76
3 76
3 76
3 76
G26-50 5 feet (1.5 m) with two 90_ elbows of 1-1/2 inch (38 mm) diameter pipe. (15 equivalent feet (4.6 m) total).
G26-75 5 feet (1.5 m) with two 90_ elbows of 2 inch (51 mm) diameter pipe. (15 equivalent feet (4.6 m) total).
G26-100 5 feet (1.5 m) with two 90_ elbows of 2 inch (51 mm) diameter pipe. (15 equivalent feet (4.6 m) total).
G26-125 5 feet (1.5 m) with two 90_ elbows of 2 inch (51 mm) diameter pipe. (15 equivalent feet (4.6 m) total).
GAS PIPE CAPACITY − FT
10 20 30
(3.048) (6.096) (9.144)
43 29 24
(1.13) (.82) (.68)
95 65 52
(2.69) (1.84) (1.47)
175 120 97
(4.96) (3.40) (2.75)
360 250 200
(10.19) (7.08) (5.66)
680 465 375
(19.25) (13.17) (10.62)
1400 950 770
(39.64) (26.90) (21.80)
2100 460 1180
(59.46) (41.34) (33.41)
3950 2750 2200
(111.85) (77.87) (62.30)
6300 4350 3520
(178.39) (123.17) (99.67)
11000 7700 6250
(311.48) (218.03) (176.98)
23000 15800 12800
(651.27) (447.39) (362.44)
Minimum Vent Pipe Diameter Required
100,000 Btuh (29.3 kW)
in. mm in.
2 51 2
2 51 2
2 51 2
2 51 3
2 51 3
2 51 3
2 51 3
3 76 3
3 76 3
3 76 3
3 76 3
3 76 3
3 76 3
3 76 3
3 76 3
3
/HR (kL/HR)
Length of Pipe−Feet(m)
40 50 60
(12.192) (15.240) (18.288)
20 18 16
(.57) (.51) (.45)
45 40 36
(1.27) (1.13) (1.02)
82 73 66
(2.32) (2.07) (1.87)
170 151 138
(4.81) (4.28) (3.91)
320 285 260
(9.06) (8.07) (7.36)
660 580 530
(18.69) (16.42) (15.01)
990 900 810
(28.03) (25.48) (22.94)
1900 1680 1520
(53.80) (47.57) (43.04)
3000 2650 2400
(84.95) (75.04) (67.96)
5300 4750 4300
(150.07) (134.50) (121.76)
10900 9700 8800
(308.64) (274.67) (249.18)
Page 7
125,000 Btuh (36.6 kW)
mm in.
51 2
51 3
51 3
51 3
51 3
51 3
76 3
76 3
76 3
76 3
76 3
76 3
76 3
76 3
76 - - - -
70 80 90
(21.336) (24.384) (27.432)
15 14 13
(.42) (.40) (.37)
33 31 29
(.73) (.88) (.82)
61 57 53
(1.73) (1.61) (1.50)
125 118 110
(3.54) (3.34) (3.11)
240 220 205
(6.80) (6.23) (5.80)
490 460 430
(13.87) (13.03) (12.18)
750 690 650
(21.24) (19.54) (18.41)
1400 1300 1220
(39.64) (36.81) (34.55)
2250 2050 1950
(63.71) (58.05) (55.22)
3900 3700 3450
(110.43) (104.77) (97.69)
8100 7500 7200
(229.36) (212.37) (203.88)
mm
51
76
76
76
76
76
76
76
76
76
76
76
76
76
- - - -
100
(30.480)
12
(.34)
27
(.76)
50
(1.42)
103
(2.92)
195
(5.52)
400
(11.33)
620
(17.56)
1150
(32.56)
1850
(52.38)
3250
(92.03)
6700
(189.72)