Vermont Casting 43LDVT 사용자 설명서

13

FP1012

Top vent max run

1/25/00   djt

20' (6m)

7.5' (2.3m)

Pipe Straps 

Every 3’ (914mm)

Firestop/Zero 

Clearance Sleeve

Pipe 

Straps Every 

3’ (914mm)

FP1012

Fig. 14  Support straps for horizontal runs.

• 

If a 90° elbow is used in the horizontal vent run 
(level height maintained) the maximum horizontal 
vent length is reduced by 36” (914mm). This does  
not apply if the 90° elbows are used to increase or 
redirect a vertical rise.

  Example: According to the chart the maximum  

horizontal vent length in a system with a 7.5’ (2.3 m) 
vertical rise  is 20’ (6m) and if a 90° is required in the 
horizontal vent it must be reduced to 17’ (5.2 m).

  In Figure 16, Dimension A plus B must not be 

greater than 17’ (5.2 m).

Horizontal plane means no vertical rise exists on this 
portion of the vent assembly. 

• 

The maximum number of 90° elbows per side wall 
installations is three (3).

• 

If a 90° elbow is fitted directly onto the fireplace  
flange the maximum horizontal vent run before the 
termination or a vertical rise is 36” (914mm).

3'

(914mm)

FP1237

horizontal plane

12/02

FP1237

Fig. 15  Maximum horizontal vent run.

7.5'

(2.3m)

A

B

A + B = 17' (5.2m) Max.

1 x 90° elbow in horizontal plane = 3’ (914mm)

FP1238

Fig. 16  Maximum vent run with elbows.

• 

The maximum number of 45° elbows permitted per 
side wall installation is two (2). These elbows can be 
installed in either the vertical or horizontal run.

• 

For each 45° elbow installed in the horizontal run, 
the length of the horizontal run MUST be reduced by 
18” (457 mm). This does not apply if the 45° elbows 
are installed on the vertical part of the vent system.

• 

The maximum number of elbow degrees in a system 
is 270°. (Fig. 17)

Example: 
 

Elbow 1  =  90°

 

Elbow 2  =  45° 

 

Elbow 3  =  45°

 

Elbow 4  =  90°

  Total angular variation  =  270°

1 + 2 + 3 + 4 = 270°

FP1239

Fig. 17  Maximum number of elbow degrees.

1

2

3

4