Lenox Lennox Merit Series Gas Furnace Upflow/Horizontal air discharge, ML180UHE 130

TABLE 7

Vent Connector Capacity

Type B Double−Wall Vents with Single−Wall Metal Connectors

Serving Two or More Category I Appliances

					Vent and Connector Diameter − D (inches)
Height	Lateral
			3 Inch		4 Inch			5 Inch			6 Inch
H	L
					Appliance Input Rating in Thousands of Btu Per Hour
(feet)	(feet)
		MIN		MAX	MIN	MAX	MIN		MAX	MIN		MAX
	1	NA		NA	NA	NA	NA		NA	NA		NA
6	2	NA		NA	NA	NA	NA		NA	168		182
	3	NA		NA	NA	NA	121		131	175		198
	1	NA		NA	NA	NA	NA		NA	NA		NA
8	2	NA		NA	NA	NA	125		126	184		193
	3	NA		NA	NA	NA	130		138	191		208
	1	NA		NA	NA	NA	119		121	182		186
10	2	NA		NA	84	85	124		134	189		203
	3	NA		NA	89	91	129		144	197		217
	1	NA		NA	79	87	116		138	177		214
15	2	NA		NA	83	94	121		150	185		230
	3	NA		NA	87	100	127		160	193		243
	1	49		56	78	97	115		152	175		238
20	2	52		59	82	103	120		163	182		252
	3	55		62	87	107	125		172	190		264
	1	47		60	77	110	112		175	169		278
30	2	51		62	81	115	117		185	177		290
	3	54		64	85	119	122		193	185		300

NOTE − Single appliance venting configurations with zero lateral lengths are assumed to have no elbows in the vent system. For all other vent configurations, the vent system is assumed to have two 90° elbows. For each additional 90° elbow or equivalent (for example two 45° elbows equal one 90° elbow) beyond two, the maximum capacity listed in the venting table should be reduced by 10 percent (0.90 x maxi- mum listed capacity).

TABLE 8

Common Vent Capacity

Type B Double−Wall Vents with Single−Wall Metal Connectors

Serving Two or More Category I Appliances

Vent				Common Vent Diameter − D (inches)
Height	4 Inch		5 Inch			6 Inch		7 Inch
H			Appliance Input Rating in Thousands of Btu Per Hour
(feet)
	FAN + FAN	FAN + NAT	FAN + FAN		FAN + NAT	FAN + FAN	FAN + NAT	FAN + FAN	FAN + NAT
6	NA	78	NA		113	200	158	304	244
8	NA	87	NA		126	218	173	331	269
10	NA	94	163		137	237	189	357	292
15	121	108	189		159	275	221	416	343
20	131	118	208		177	305	247	463	383
30	145	132	236		202	350	286	533	446

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