Napoleon Fireplaces BGD40-N Horizontal Termination, 45º H1, Definitions, Elbow Vent Length Values

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		DEFINITIONS		ELBOW VENT LENGTH VALUES
for the following symbols used in the venting calcula-					feet	inches
tions and examples are:
			1°		0.03	0.5
>	-	greater than
			15°		0.45	6.0
>	-	equal to or greater than	30°		0.9	11.0
<	-	less than	45°*		1.35	16.0
<	-	equal to or less than	90°*		2.7	32.0
HT	-	total of both horizontal vent lengths (HR) and off-
sets (HO) in feet				* the first 45º and 90° offset has a zero value and is
H -		combined horizontal vent lengths in feet
HRO -		offset factor: .03(total degrees of offset - 135°*) in		shown in the formula as -45°and -90ºrespectively or
VT -		feet		-135ºwhen combined.
		combined vertical vent lengths in feet

HORIZONTAL TERMINATION

when (HT) < (VT)

Simple venting configuration (only one 45º and 90° elbow)

90°

FIGURE5

For vent configurations requiring more than one 45º and 90° elbow, the following formulas apply:

Formula 1: HT < VT

Formula 2: HT + VT < 40 feet

Example 1:	H2
	90°

		V1
45º
	FIGURE6

45º

H1 90°

HT - total of both horizontal vent lengths (HR) and offsets (HO) in feet

REQUIRED

VERTICAL RISEINFEET (VT)

CALCULATED HORIZONTAL VENT RUN PLUS OFFSETS IN FEET (HT)

The shaded area within the lines represents acceptable values for HT and VT .

V1	=	8 ft
VT	= V1 = 8 ft
H1	=	2.5 ft
H2	=	2 ft
HR	= H1 + H2 = 2.5 + 2 = 4.5 ft
HO	= .03(one 45º elbow + two 90º elbows - 135º)
=0.3(225-135º) = 2.7ft
HT	= HR + HO = 4.5 + 2.7 = 7.2 ft
HT + VT = 7.2 +8 =15.2ft
Formula 1:			HT < VT
			7.2 < 8
Formula 2:			HT + VT < 40 feet
			15.2 < 40

Since both formulas are met, this vent configuration is ac- ceptable.

W415-0299/C/03.12.03