Vermont Casting DVBR36 Twist Lock Pipes, How to Use the Vent Graph, Rear Wall Vent Applications

Twist Lock Pipes

When using CFM Corporation twist-lock pipe, it is not necessary to use silicone to seal the twist-lock joints. The only areas that need silicone are the collars on the fireplace, the telescoping pipe (if used) and the hori- zontal termination connection (when necessary). The female (flared) end secures to the fireplace first with the male end away from the fireplace.

To join the pipes together, simply align the beads of the male end with the grooves of the female end, twisting the pipe until the flange on the female end touches the external bead on the male end. Secure the joints with three (3) sheet metal screws. (Fig. 17)

To make assembly easier, apply lubricant (vaseline or similar) on the male end of the twist-lock pipe.

Male End	Female
	End
Screw Holes	TWL100

Fig. 17 Twist-Lock pipe joints.

How to Use the Vent Graph

The Vent Graph should be read in conjunction with the following vent installation instructions to determine the relationship between the vertical and horizontal dimen- sions to 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. 18), locate the point intersecting with the 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 unit is 11 feet (3352 mm) the horizontal run to the face of the outer wall must not exceed 14’ (4267 mm).

EXAMPLE B:

If the vertical dimension from the floor of the unit is 7’ (2133mm), the horizontal run to the face of the outer wall must not exceed 8¹⁄₂’ (2590 mm).

DVBR Series Direct Vent Gas Fireplace

30
29
28
27
26
25
24
23	tothe	Vertical
22
21
20	CenteroftheHorizontalVentPipe	DimensionfromtheFlooroftheUnit
19
18
17
16
15
14
13
12	eg: A
11
10

9
8
7	eg: B
6
5
4
3

34 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Horizontal Dimension from the Outside Face of the Wall to the Center of the Fireplace Vent Flange

DV Graph

Fig. 18 Sidewall venting graph. (Dimensions in feet.)

Refer to Page 19 for venting requirements for snorkels.

Rear Wall Vent Applications

When installed as a rear vent unit this appliance may be vented directly to a termination located on the rear wall behind the appliance.

•Only CFM Corporation venting components are ap- proved to be used in these applications (See ‘Venting Components’ listed for different installation require- ments).

•The maximum horizontal distance between the rear of the appliance (or end of the transition elbow in a corner application) and the outside face of the rear wall is 20” (508mm). (Fig. 19, 20 )

•Only one 45° elbow is allowed in these installations.

•Minimum clearances between vent pipe and com- bustible materials are as follows:

Top - 2” (51 mm)

Sides - 1” (25 mm)

Bottom - 1” (25 mm)

20000584 13