Bryant 355MAV instruction manual Maximum Allowable Pipe Length ft, Altitude FT

Table 7—Maximum Allowable Pipe Length (ft)

ALTITUDE (FT)	UNIT SIZE	TERMINATION	PIPE DIA			NUMBER OF 90° ELBOWS
		TYPE	(IN.)*	1	2		3	4	5	6
	042040	2 Pipe or 2-in	1-1/2	50	45		40	35	30	25
		Concentric	2	70	70		70	70	70	70
	042060	2 Pipe or 2-in	1-1/2	50	45		40	35	30	25
		Concentric	2	70	70		70	70	70	70
	042080	2 Pipe or 2-in	1-1/2	30	25		20	15	10	5
0 to 2000	060080	Concentric	2	70	70		70	70	70	70
	060100	2 Pipe or 2-in	2	45	40		35	30	25	20
		Concentric	2-1/2	70	70		70	70	70	70
		2 Pipe or 3-in.	2-1/2	10	NA		NA	NA	NA	NA
	060120		3	35	30		15	NA	NA	NA
		Concentric
			3†	70	70		70	70	70	70
ALTITUDE (FT)	UNIT SIZE	TERMINATION	PIPE DIA			NUMBER OF 90° ELBOWS
		TYPE	(IN.)*	1	2		3	4	5	6
	042040	2 Pipe or 2-in	1–1/2	45	40		35	30	25	20
		Concentric	2	70	70		70	70	70	70
	042060	2 Pipe or 2-in	1–1/2	45	40		35	30	25	20
		Concentric	2	70	70		70	70	70	70
2001 to 3000	042080	2 Pipe or 2-in	1–1/2	26	21		16	11	6	NA
	060080	Concentric	2	70	70		70	70	70	70
	060100	2 Pipe or 2-in	2	40	35		30	25	20	15
		Concentric	2–1/2	70	70		70	70	70	70
	060120	2 Pipe or 3-in.	3	31	26		12	NA	NA	NA
		Concentric	3†	63	62		62	61	61	61
ALTITUDE (FT)	UNIT SIZE	TERMINATION	PIPE DIA			NUMBER OF 90° ELBOWS
		TYPE	(IN.)*	1	2		3	4	5	6
	042040	2 Pipe or 2-in	1-1/2	42	37		32	27	22	17
		Concentric	2	70	70		70	70	70	70
	042060	2 Pipe or 2-in	1-1/2	42	37		32	27	22	17
		Concentric	2	70	70		70	70	70	70
3001 to 4000	042080	2 Pipe or 2-in	1-1/2	25	20		15	10	5	NA
	060080	Concentric	2	70	70		70	70	70	70
	060100	2 Pipe or 2-in	2	38	33		28	23	18	13
		Concentric	2-1/2	70	70		70	70	70	70
	060120	2 Pipe or 3-in.	3	29	24		10	NA	NA	NA
		Concentric	3†	59	59		58	57	57	56

See notes at end of table.

NOTE: Do not count elbows or pipe sections in terminations or within furnace. See shaded areas in Fig. 40, 41, 42, 43, and 44.

EXAMPLE: An 042080 size furnace located in Indianapolis, elevation 650 ft above sea level, could be installed in an application requiring 3 elbows and 17 ft of vent pipe, along with 5 elbows and 16 ft of combustion-air pipe. Table 7 indicates this application would allow a 1-1/2-in. diameter vent pipe, but require a 2-in. diameter combustion air pipe (1-1/2-in. pipe is good for 20 ft with 3 elbows, but only 10 ft with 5 elbows). Therefore, 2-in. diameter pipe must be used for both vent and combustion-air pipes since larger required diameter must always be used for both pipes. If same installation were in Albuquerque, elevation 5250 ft above sea level, installation would require 2-in. vent pipe and combustion-air pipe. At 5001- to 6000-ft elevation, 1-1/2-in. pipe is not allowed with 5 elbows, but 2-in. pipe is good for 68 ft with 5 elbows.

COMBUSTION-AIR AND VENT PIPE ATTACHMENT

NOTE: All pipe joints must be watertight except attachment of combustion-air pipe to inlet housing connection, since it may be necessary to remove pipe for servicing.

1.Attach combustion-air pipe to furnace as follows:

a.Determine location of combustion-air intake pipe connection to combustion-air intake housing as shown in Fig. 36 for application.

b.Reposition combustion-air intake housing plug fitting in appropriate unused intake housing connection.

c.If required, insert perforated disk assembly (factory-supplied in loose parts bag) in intake housing where combustion-air intake pipe will be connected. If half disk set is required, install with shoulder of disk against stop in combustion-air inlet.

d.Install pipe support (factory-supplied in loose parts bag) into selected furnace casing combustion-air pipe hole. Pipe support should be positioned at bottom of casing hole.

e.Insert 2-in. diameter pipe into intake housing.

f.Install casing hole filler cap (factory-supplied in loose parts bag) in unused combustion-air pipe casing hole.

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