W415-0381 / H / 12.07.07

13

VERTICAL TERMINATION

when (HT) > (VT)

Simple venting confi gurations

FIGURE 12

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

REQUIRED

VERTICAL

R I S E I N

FEET (VT)

Example 4:

V1

=1 ft

V2

=1.5 ft

VT

= V1 + V2 = 1 + 1.5 = 2.5 ft

H1

=6 ft

H2

=2 ft

HR

= H1 + H2 = 6 + 2 = 8 ft

HO

= .03(one 45º elbow + three 90º elbow - 135º)

 

= .03(45 + 90 + 90 + 90 - 135) = 5.4 ft

HT

=HR + HO = 8 + 5.4 = 13.4 ft

HT + VT

= 13.4 + 2.5 = 15.9 ft

Formula 1: HT < 3VT

3VT = 3 x 2.5 = 7.5 ft

13.4 > 7.5

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

Formula 2: HT + VT < 40 feet 15.9 < 40

Since only formula 2 is met, this vent configuration is unacceptable and a new fi replace location or vent con-

guration will need to be established to satisfy both formulas.

HORIZONTAL VENT RUN PLUS OFFSET IN FEET (HT)

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

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

Formula 1: HT < 3VT

Formula 2: HT + VT < 40 feet

90°

 

H2

 

V2

 

45°

 

H3

 

 

 

 

 

 

 

 

 

 

 

H1

V1

45°

90°

 

 

 

 

FIGURE 14

90°

45°

90° V2

H1H2

V1

90° 90°

FIGURE 13

Example 5:

V1

=1.5 ft

V2

=8 ft

VT

= V1 + V2 = 1.5 + 8= 9.5 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 + two 45° elbows - 135°)

 

= .03(90 + 90 + 90 + 45 + 45 - 135) = 6.75 ft

HT

=HR + HO = 12.75 + 6.75 = 19.5 ft

HT + VT = 19.5 + 4.5= 24 ft

Formula 1: HT < 3VT

3VT = 3 x 9.5 = 28.5 ft

19.5< 28.5

Formula 2: HT + VT < 40 feet

24 < 40

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

Page 13
Image 13
Napoleon Fireplaces BGP42, BGD42 manual Formula 1 HT 3VT Formula 2 HT + VT 40 feet