Rear Vent Vertical Venting Runs - Montigo M40DV-CR Installation Operation & Maintenance

Vertical Vent Installations
Vertical Installations with a rise greater than 12' can be reduced

from 5/8 to 4/7 venting.
• minimum 2' (two feet) above the highest point where
vent passes through the roof.
• minimum 6' (six feet) from a mechanical air inlet
• minimum 18" (1 1/2 feet) from a parapet wall.
Maximum vent height is 30 feet above fireplace.

Note: Flame characteristics will change if the maximum vent
height is used.
Minimum clearance to combustible construction around the

vent pipe is 1" on all sides must be maintained, except on hori-
zontal venting where the top of the pipe must have a clearance of
at least 2".
1. Straight Vertical Installation
Figure 9. Straight, vertical venting. When the vent run is not reduced
use a PEL-90F/F elbow, which is connected directly to the
fireplace flue collar. In this case, the PXT-10 adaptor is not
needed. * If reducing to 4"/7" venting see figure 19.
2. Offset Vertical Installations
A maximum of two offsets (each offset has two 90° bends) may be

made if the length of the offsets does not exceed 25% of the vertical
vent height, when measured center to center of piping.
Example: Typical vent installation.
30' vertical vent
2 - 2' offsets required
25% of 30' = 7-1/2' max. offset allowed
This venting configuration meets requirements.
P/N XG0206
Installation
Figure 10a. Vertical venting with 1 offset (1 offset= two 90° bends).
* If reducing to 4"/7" venting see figure 19.
Figure 10b. Vertical venting with 2 offsets (1 offset= two 90° bends).
* If reducing to 4"/7" venting see figure 19.
M40DV-CR/CL Corner Gas Fireplace
Rear Vent
Page 9