Mendota FV46, Инструкция по установке и эксплуатации

Страница: 63 / 96

85-03-01108 FV46 Page 63
Maximum Horizontal Run
• Maximum Horizontal Run allowed is 20 feet if a vertical starter section of 4 feet to 30 feet is connected directly to the
fireplace’s flue starter collar, and no more than three 90-degree elbows are used.
•
18” maximum horizontal run allowed with the minimum 12” vertical rise.
Maximum Vent System Length
Combined total length of all straight pipe sections in the vent system shall be less than or equal to 54 feet.
How to Calculate the Vent Lengths
For calculation purposes and usage of charts in this manual, simply add the lengths of all individual straight pipe sections. For
example: if you use two 2-foot lengths and one 4-foot length, the total vent system length will be 2+2+4 = 8 feet.
Using 90
0
Elbows in Zone “B”
The fireplace allows maximum flexibility in the use of 90 o elbows in the vent system. The length of the first straight vertical
section directly connected to the fireplace’s starter collar determines the maximum horizontal run and the number of 90 0 elbows
allowed for this fireplace.
For vent systems with a starting vertical section that is 4 feet to 30 feet long, you may connect up to 20 feet of horizontal pipe
and up to three 90 0 elbows within the 20 feet run in any configuration and terminate the vent horizontally. Four 90 0 elbows can
be used if terminated vertically. No reduction in horizontal run is required for the elbows used.
Using 90 0 elbows In Zone “A”.
For vent systems that provide a starting vertical section less than 4 feet, the following rules apply:
a. You must use the Master Venting Chart. See Zone “A” below the 4’ vertical run line.
b. A single 90
º
vertical-to-horizontal elbow is already calculated into the allowable maximum 20' horizontal run. The Venting
Requirements Chart assumes that for all horizontal runs calculated, one 90 0 elbows is used within the venting system. Each
additional 90
º
elbow reduces the maximum horizontal distance by 3'.
c. If you plan to use more than one 90 0 elbows within the vent system, first use the Master Venting Chart and calculate the
maximum horizontal run you are allowed based on the first vertical section connected directly to the fireplace. From this
maximum horizontal run calculated, subtract 3 feet for each additional 90
0
elbow you will use.
Example 1: Assume you are using a 3 feet long starter vertical section. This should allow, per Master Venting Chart, 13’-4” of
horizontal run. If you want to use three 90 0 elbows, subtract 6 feet for two elbows from the 13’-4” maximum allowed [3 feet for
each elbow after the first elbow]. This yields 7’-4”as the maximum horizontal run that you are allowed to install using the 3-foot
vertical starter section.
CAUTION: If a vertical-to-horizontal discharge elbow or a horizontal-to-horizontal discharge elbow is enclosed within a wall,
floor or ceiling, a top air space clearance of 3" must be maintained.
Using 45-Degree Elbows
Two 45-degree elbows may be used in place of one 90-degree elbow. On 45-degree runs, one foot of diagonal pipe is equal to 8-
1/2 inches horizontal run and 8-1/2 inches vertical run.
Two 45-degree elbows may be connected directly to the top of this fireplace to create a horizontal offset. 20 feet maximum
horizontal run allowed with this offset configuration only if the first vertical section connected directly to the last 45-degree
elbow is more than 4 feet long. For maximum allowable horizontal distances with the 45-degree offsets, see the Master Venting
Configuration Chart.
Note: Each horizontally positioned 45
º
elbow reduces the maximum horizontal distance by 1½ '.
SUPPORT: Horizontal runs of pipe will require one vent support for every 3 ft. of pipe.