Lennox Hearth MN54-VDLPM, MN04-VDLPM Horizontal Vent FIGURES/TABLES, Exterior Wall Thickness

HORIZONTAL VENT FIGURES/TABLES

Note: Secure Vent components (rigid vent pipe and terminal) are shown in the figures; Secure Flex components (flexible vent pipe and terminal) may also be used.

Note: Two 45 degree elbows may be used in place of one 90 degree elbow. The same rise to run ratios, as shown in the venting figures for 90 degree elbows, must be followed if 45 degree elbows are used.

Note: It is very important that the horizontal/inclined run be main- tained in a straight (no dips) and recommended to be in a slightly elevated plane, in a direction away from the fireplace of 1/4" rise per foot (20 mm per meter) which is ideal, though rise per foot run ratios that are smaller are acceptable all the way down to at or near level.

Note: SV4.5VF (Secure Vent), SF4.5VF (Secure Flex) firestop/spacer must be used anytime vent pipe passes through a combustible floor or ceiling. Lennox MPLDV35"/40" & 45" models require 5" clearances to combustibles above horizontal vent runs when the centerline of the horizontal vent run is at or below 48" (1219 mm) above the fireplace top wrapper. In all other instances, with these three models and with the MPLDV30 in all instances, the clearance to combustibles above horizon- tal vent runs is 3". Please note that to facilitate the 5" clearance when required, we have two 5" clearance firestops. The SV4.5HF5 is for use with rigid (Secure Vent™ ) and the SF4.5HF5 is for use with (Secure Flex™ ). These firestops should be used whenever horizontal vent runs meeting the use requirements detailed above, penetrate walls separating occupied rooms in a house.

Each of our horizontal terminations are shipped with a standard 3" clearance horizontal firestop. In ALL cases this firestop may be used at the exterior wall regardless of any circumstances that may require the 5" clearance to combustibles above the horizontal vent component. The firestop provided with the termination is not specific for use with any particular clearance height.

The SV4.5HF or SF4.5HF firestop provided with each termination can be used as shown in Figure 29 when fitted at the exterior wall adjacent to the termination.

WARNING: UNDER NO CIRCUMSTANCES MAY SEPA- RATE SECTIONS OF CONCENTRIC FLEXIBLE VENT PIPE BE JOINED TOGETHER.

TABLE 3

Venting Components Required for Various Exterior Wall

Thicknesses, When Using The Square Termination (SV4.5HT-2)

Venting Components Required	Exterior Wall Thickness
	inches (mm)
Termination Kit Only	6 to 9-1/4 (152 to 235)
Termination Kit and 6 in. Vent	10-1/2 to 13-3/4 (267 to 349)
Section (SV4.5L6)
Termination Kit and 12 in. Vent	16-1/2 to 19-3/4 (419 to 502)
Section (SV4.5L12)
Termination Kit and Telescopic
Section (SV4.5LA 2 to 7-12 in.)	11 to 19-3/4 (279 to 502)
& 6 in. vent section (SV4.5L6)

	SV4.5HF/SF4.5HF
	Firestop
3”	1”
1”	1”
	3” Clearance

Stud Framing

Top Spacer

SV4.5HF/SF4.5HF

Firestop

5”

1”

1”

1”

5” Clearance

Stud Framing

Top Spacer

18

Figure 29

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.