Napoleon Fireplaces GD19N, GD19P manual Ht Vt

(HT) > (VT)

Simple venting configurations

FIGURE 17

See graph to determine the required vertical rise VT for the required horizontal run HT.

REQUIRED

VERTICAL

RISE IN

FEET VT

HORIZONTAL VENT RUN PLUS OFFSET IN FEET HT

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

For vent configurations requiring more than two 90° elbow (top exit) or one 90° elbow (rear exit), the following formulas apply:

Formula 1: HT < 3VT

Formula 2: HT + VT < 35 feet

90°			90°		V3
V		H1		H
	1		V2		2
				90°	90°

FIGURE 18

15

Example 7:

V1		=2 ft
V2		=1 ft
V3		=1.5 ft
VT		= V1 + V2 + V3 = 2 + 1 + 1.5 = 4.5 ft
H1		=6 ft
H2		=2 ft
HR		= H1	+ H2 = 6 + 2 = 8 ft
HO		= .03(four 90° elbows - 90°)
		= .03(90 + 90 + 90 + 90 - 90) = 8.1 ft
HT	+ VT	=HR + HO = 8 + 8.1 = 16.1 ft
HT		= 16.1 + 4.5 = 20.6 ft
Formula 1:			HT	<	3VT
					3VT = 3 x 4.5 = 13.5 ft
			16.1 > 13.5

Since this formula is not met, this vent configuration is unacceptable.

Formula 2: HT + VT < 35 feet 20.6 < 35

Since only formula 2 is met, this vent configuration is unacceptable and a new fireplace location or vent configuration will need to be established to satisfy both formulas.

Example 8:

			90°		H2 45°		V2
			H1	V1		H3	90°
					90°
						FIGURE 19
V1		=1.5 ft
V2		=5 ft
VT		= V1 + V2 = 1.5 + 5 = 6.5 ft
H1		=1 ft
H2		=1 ft
H3		=10.75 ft
HR		= H1	+ H2	+ H3		= 1 + 1 + 10.75 = 12.75 ft
HO		= .03(three 90° elbows + one 45° elbow - 90°)
		= .03(90 + 90 + 90 + 45 - 90) = 6.75 ft
HT		=HR + HO			= 12.75 + 6.75 = 19.5 ft
HT	+ VT	= 19.5 + 6.5 = 26 ft
Formula 1:			HT < 3VT
				3VT		= 3 x 6.5 = 19.5 ft
			19.5 = 19.5

Formula 2: HT + VT < 35 feet 26 < 35

Since both formulas are met, this vent configuration is acceptable.

W415-0612 / C / 01.25.08