Lennox Hearth MPD-33 Series Vertical Termination Systems Roof, Vent Section Length Chart

VERTICAL TERMINATION SYSTEMS (ROOF)

Figure 16, and Figures 26 through 30 on pages 14 and 15 and their associated Vertical Vent Tables illustrate the various verti- cal venting configurations that are possible for use with these appliances. Secure Vent pipe applications are shown in these figures; Secure Flex pipe may also be used. A Vertical Vent Table summarizes each system’s minimum and maximum vertical and horizontal length values that can be used to design and install the vent components in a variety of applications.

Both these vertical vent systems terminate through the roof. The minimum vent height above the roof and/or adjacent walls is speci- fied in ANSI Z223.1-(latest edition) (In Canada, the current CAN-1 B149 installation code) by major building codes. Always consult your local codes for specific requirements. A general guide to follow is the Gas Vent Rule (refer to

Figure 4 on page 5).

Vertical (Straight) Installation

Determine the number of straight vent sections required. 4-1/2" (114 mm), 10-1/2" (267 mm), 22-1/2" (572 mm), 34-1/2" (876 mm) and 46- 1/2" (1181 mm) net section lengths are avail- able. Plan the vent lengths so that a joint does not occur at the intersection of ceiling or roof joists. Refer to the Vent Section Length Chart.

SV4.5CGV-1	SV4.5FA OR
Termination
	SV4.5FB Flashing
	AND SV4.5SC
	STORM COLLAR

			1" (25.4 mm)
			Minimum
			Clearance to
			Combustibles
			*SV4.5VF
			Firestop/Spacer
40'	Max		SV4.5L6/12/24/36/48
(12.2		M)
			Vent Sections
			*When using Secure Flex,
			use Firestop/Spacer
			SF4.5VF

VENT SECTION LENGTH CHART

Nominal		6		12	24	36		48	T
Section Length									O
(inches)									T
Net Section		4-1/2		10-1/2	22-1/2	34-1/2	46-1/2		A
Length (inches)									L
Height of Vent			Number of Vent Sections						Q
									T
inches	ft
									Y
4.5	0.375	1		0	0	0		0	1
9	0.75	2		0	0	0		0	2
10.5	0.875	0		1	0	0		0	1
15	1.25	1		1	0	0		0	2
19.5	1.625	2		1	0	0		0	3
21	1.75	0		2	0	0		0	2
22.5	1.875	0		0	1	0		0	1
25.5	2.125	1		2	0	0		0	3
31.5	2.625	0		3	0	0		0	3
34.5	2.875	0		0	0	1		0	1
37.5	3.125	1		1	1	0		0	3
43.5	3.625	0		2	1	0		0	3
45	3.75	0		0	2	0		0	2
46.5	3.875	0		0	0	0		1	1
49.5	4.125	1		0	2	0		0	3
51	4.25	1		0	0	0		1	2
55.5	4.625	0		1	2	0		0	3
57	4.75	0		0	1	1		0	2
66	5.25	0		2	2	0		0	4
67.5	5.625	0		0	3	0		0	3
69	5.75	0		0	0	2		0	2
72	6	1		0	3	0		0	4
73.5	6.125	1		0	0	2		0	3
79.5	6.625	0		1	0	2		0	3
81	6.75	0		0	0	1		1	2
90	7.5	0		2	1	0		1	4
91.5	7.625	0		0	2	0		1	3
93	7.75	0		0	0	0		2	2
96	8	1		0	1	2		0	4
97.5	8.125	1		0	0	0		2	3
102	8.5	2		0	0	0		2	4
103.5	8.625	0		0	0	3		0	3
108	9	1		0	0	3		0	4
114	9.5	0		2	0	0		2	4
117	9.75	1		0	5	0		0	6
118.5	9.875	1		1	0	3		0	5
126	10.5	0		0	1	3		0	4
130.5	10.875	1		0	1	3		0	5
135	11.25	0		0	6	0		0	6
138	11.5	0		0	0	4		0	4
139.5	11.625	0		0	0	0		3	3
142.5	11.875	1		0	0	4		0	5

		VENT SECTION LENGTH CHART
Nominal Section			6		12	24	36	48	T
Length (inches)									O
									T
Net	Section
			4-1/2		10-1/2	22-1/2	34-1/2	46-1/2	A
Length (inches)
									L
Height of Vent				Number of Vent Sections					Q
inches		ft							T
									Y
144		12	1		0	0	0	3	4
150		12.5	0		1	0	0	3	4
154.5		12.875	1		1	0	0	3	5
160.5		13.375	0		2	0	0	3	5
172.5		14.375	0		0	0	5	0	5
177		14.75	1		0	0	5	0	6
183		15.25	0		1	0	5	0	6
186		15.5	0		0	0	0	4	4
190.5		15.875	1		0	0	0	4	5
196.5		16.375	0		1	0	0	4	5
205.5		17.125	0		1	1	5	0	7
207		17.25	0		0	0	6	0	6
211.5		17.625	1		0	0	6	0	7
217.5		18.125	0		1	0	6	0	7
229.5		19.125	0		0	1	6	0	7
232.5		19.375	0		0	0	0	5	5
237		19.75	1		0	0	0	5	6
241.5		20.125	0		0	0	7	0	7
246		20.5	1		0	0	7	0	8
252		21	0		1	0	7	0	8
264		22	0		0	1	7	0	8
276		23	0		0	0	8	0	8
279		23.25	0		0	0	0	6	6
280.5		23.375	1		0	0	8	0	9
283.5		23.625	1		0	0	0	6	7
289.5		24.125	0		1	0	0	6	7
301.5		25.125	0		0	1	0	6	7
310.5		25.875	0		0	0	9	0	9
315		26.5	1		0	0	9	0	10
325.5		27.125	0		0	0	0	7	7
330		27.5	1		0	0	0	7	8
336		28	0		1	0	0	7	8
345		28.75	0		0	0	10	0	10
349.5		29.125	1		0	0	10	0	11
372		31	0		0	0	0	8	8
376.5		31.375	1		0	0	0	8	9
379.5		31.625	0		0	0	11	0	11
418.5		34.875	0		0	0	0	9	9
423		35.25	1		0	0	0	9	10
465		38.75	0		0	0	0	10	10

Figure 16

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

11