Справочник Пользователя для Vermont Casting 20DVT

10

The vent chart should be read in conjunction with the 
following vent installation instructions to determine the 
relationship of the vertical and horizontal dimensions of 
the vent system.
1.  Determine the height of the center of the horizontal 

vent pipe exiting through the outer wall.  Using this 
dimension on the Sidewall Vent Graph (Fig. 10) 
locate the point intersecting with slanted graph line. 

2.  From the point of this intersection, draw a vertical 

line to the bottom of the graph.

3.  Select the indicated dimension, and position the 

fireplace in accordance with same. 

  Example A:
  If the vertical dimension from the floor of the    

fireplace is 11’ (3.4 m) the horizontal run to the face  
of the outer wall must not exceed 14’ (4.3 m).

  Example B:
  If the vertical dimension from the floor of the unit is  

7’ (2.14 m), the horizontal run to the face of the outer  
wall must not exceed 8¹⁄₂’ (2.6 m).

Horizontal dimension from the outside face of the 

wall to the center of the fireplace vent flange

Sidewall vent graph showing the relationship between vertical        

and horizontal dimensions for a Direct Vent flue system.

V

ertical dimension from the fl

oor of the unit

to the center of the horizontal vent pipe

Fig. 10  Sidewall venting graph. (Dimensions in feet)

TWL100
Twist Lock Pipe
3/12/99   djt

Male End

Female End

Screw Holes

TWL100

Fig. 9   Twist-lock pipe joints.

When using CFM Corporation twist-lock pipe it is not 
necessary to use sealant on the joints. The only areas 
of the venting system that need to be sealed with high 
temperature silicone sealant are the sliding joints of any 
telescopic vent section used in the system.
To join the twist lock pipes together, simply align the 
beads of the male end with the grooves of the female 
end, then while bringing the pipe together, twist the pipe 
until the flange on the female end contacts the external 
flange on the male end. It is recommended that you 
secure the joints with three (3) sheet metal screws, 
however this is not mandatory with twist lock pipe.
To make it easier to assemble the joints we suggest 
putting a lubricant (Vaseline or similar) on the male end 
of the twist lock pipe prior to assembly. 

Since it is very important that the venting system 
maintain its balance between the combustion air 
intake and the flue gas exhaust, certain limitations 
as to vent configurations apply and must be strictly 
adhered to.
The Vent Graph shows the relationship between vertical 
and horizontal side wall venting and will help to deter-
mine the various dimensions allowable. 
Minimum clearance between vent pipes and com-
bustible materials is 1”(25 mm) on top, bottom and 
sides unless otherwise noted.
When vent termination exits through foundations less 
than 20” below siding outcrop, the vent pipe must 
flush up with the siding. It is always best to locate the 
fireplace in such a way that minimizes the number of 
offsets and horizontal vent length.
The horizontal vent run refers to the total length of vent 
pipe from the flue collar of the fireplace to the face of 
the outer wall.