Desa M36B Safety guide

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NATURAL GAS MODELS
M36(B,H), M42(B,H), VM36(B,H)
AND VM42(B,H)
PROPANE/LP GAS MODELS
M36P(B,H), M42P(B,H),
VM36P(B,H) AND VM42P(B,H)
B-VENT DECORATIVE GAS FIREPLACE
OWNER’S OPERATION AND INSTALLATION MANUAL
FOR YOUR SAFETY
— Donotstoreorusegasolineoranyotherammable
vapors or liquids in the vicinity of this or any other
appliance.
— WHAT TO DO IF YOU SMELL GAS :
• Donottrytolightanyappliance.
• Donottouchanyelectricalswitch;
• Donotuseanyphoneinyourbuilding.
• Immediatelycallyourgassupplierfromaneighbor’s
phone.Followthegassupplier’sinstructions.
• Ifyoucannotreachyourgassupplier,callthere
department.
— Installationandservicemustbeperformedbyaquali-
edinstaller,serviceagencyorthegassupplier.
INSTALLER:Leavethismanualwiththeappliance.
CONSUMER:Retainthismanualforfuturereference.
WARNING:Iftheinformationintheseinstructions
isnotfollowedexactly,areorexplosionmayresult
causingpropertydamage,personalinjuryordeath.
O-TL REPORT # 114-F-16-4

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 WARNING: Improper installation, adjustment, al-
teration, service or maintenance can cause injury or
propertydamage.Refertothismanualforcorrectin-
stallation and operational procedures. For assistance
or additional information consult a qualied installer,
service agency or the gas supplier.
NOT FOR USE WITH SOLID FUEL
CHECK LOCAL CODES PRIOR TO INSTALLATION
SAVE THIS BOOK
Thisbookisvaluable.Inadditiontoinstructingyouon
howtoinstallandmaintainyourappliance,italsocon-
tainsinformationthatwillenableyoutoobtainreplace-
mentpartsoroptionalaccessoryitemswhenneeded.
Keepitwithyourotherimportantpapers.
Thisappliancemaybeinstalledinanaftermarket*,per-
manentlylocated,manufactured(mobile)home,where
notprohibitedbystateorlocalcodes.
Thisapplianceisonlyforusewiththetypeofgasindi-
cated on the rating plate.
This appliance is not convertible for use with other
gases,unlessacertiedkitisused.
*Aftermarket:Completionofsale,notforpurposeofresale,fromthemanufacturer.
StateofMassachusetts:Theinstallationmustbemade
byalicensedplumberorgastterintheCommonwealth
of Massachusetts.
TABLE OF CONTENTS
Safety .................................................................. 3
Unpacking............................................................ 4
Introduction.......................................................... 4
Selecting Location ............................................... 5
Product Specications......................................... 6
Pre-Installation Preparation................................. 7
Venting Installation .............................................. 9
Installation ..........................................................11
Operation........................................................... 19
Inspecting Burners ............................................ 20
Cleaning and Maintenance................................ 21
Wiring Diagram.................................................. 22
Replacement Parts............................................ 22
Service Hints ..................................................... 22
Technical Service............................................... 22
Troubleshooting................................................. 23
Parts .................................................................. 26
Accessories ....................................................... 31
Warranty ..............................................Back Cover

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108795-01V 3
SAFETY
1. This appliance is only for use with the type
of gas indicated on the rating plate. This
appliance is not convertible for use with
other gases unless a certied kit is used.
2. For propane/LP replace, do not place
propane/LP supply tank(s) inside any
structure. Locate propane/LP supply
tank(s) outdoors. To prevent performance
problems, do not use propane/LP fuel tank
of less than 100 lbs. capacity.
3. If you smell gas
• shut off gas supply
• do not try to light any appliance
• do not touch any electrical switch; do not
use any phone in your building
• immediately call your gas supplier from
a neighbor’s phone. Follow the gas
supplier's instructions
• if you cannot reach you gas supplier, call
the re department.
4. Never install the replace
• in a recreational vehicle
• where curtains, furniture, clothing or
other ammable objects are less than
42" from front, top or sides of replace
• in high trafc areas
• in windy or drafty areas
5. This replace reaches high temperatures.
Keep children and adults away from hot
surfaces to avoid burns or clothing igni-
tion. Fireplace will remain hot for a time
after shutdown. Allow surfaces to cool
before touching.
6. Carefully supervise young children when
they are in the room with replace.
7. A hearth extension is not required with this
appliance. If one is installed, it is for aes-
thetic purposes only and does not have
to meet the standard requirements.
8. Turn replace off and let cool before ser-
vicing or repairing. Only a qualied service
person should install, service or repair
this replace. Have replace inspected
annually by a qualied service person.
9. You must keep control compartments,
burners and circulating air passages clean.
More frequent cleaning may be needed due
to excessive lint and dust from carpeting,
bedding material, etc. Turn off the gas valve
and pilot light before cleaning replace.
10. Have venting system inspected annually by
a qualied service person. If needed, have
venting system cleaned or repaired. See
Cleaning and Maintenance, page 21.
WARNING: This product con-
tainsand/orgenerateschemicals
knowntotheStateofCalifornia
tocausecancerorbirthdefects
orotherreproductiveharm.
IMPORTANT:Readthisowner’s
manualcarefullyandcompletely
before trying to assemble, op-
erate or service this replace.
Improper use of this replace
cancauseseriousinjuryordeath
from burns, re, explosions,
electrical shock and carbon
monoxidepoisoning.
DANGER:Carbonmonoxide
poisoningmayleadtodeath!
This replace is a vented product. This replace
will not produce any gas leakage into your home
if properly installed. This replace must be
properly installed by a qualied service person.
If this unit is not properly installed by a qualied
service person, gas leakage can occur.
CarbonMonoxidePoisoning: Early signs of
carbon monoxide poisoning resemble the u,
with headaches, dizziness or nausea. If you
have these signs, the replace may not have
been installed properly. Getfreshairatonce!
Have replace inspected and serviced by a
qualied service person. Some people are more
affected by carbon monoxide than others. These
include pregnant women, people with heart or
lung disease or anemia, those under the inu-
ence of alcohol and those at high altitudes.
Propane/LP gas and natural gas are both
odorless. An odor-making agent is added
to each of these gases. The odor helps you
detect a gas leak. However, the odor added
to these gases can fade. Gas may be present
even though no odor exists.
Make certain you read and understand all
warnings. Keep this manual for reference. It
is your guide to safe and proper operation of
this replace.
WARNING: Any change to
thisreplaceoritscontrolscan
bedangerous.

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11. Keep the area around your fireplace
clear of combustible materials, gasoline
and other ammable vapor and liquids.
Do not run fireplace where these are
used or stored. Do not place items such
as clothing or decorations on or around
replace.
12. Do not use this replace to cook food or
burn paper or other objects.
13. Do not use any solid fuels (wood, coal,
paper, cardboard, etc.) in this replace.
Use only the gas type indicated on re-
place nameplate.
14. This appliance, when installed, must be
electrically grounded in accordance with
local codes or, in the absence of local
codes, with the National Electrical Code,
ANSI/NFPA 70 or the Canadian Electrical
Code, CSA C22.1.
15. Do not obstruct the ow of combustion
and ventilation air in any way. Provide
SAFETY
Continued
INTRODUCTION
adequate clearances around air open-
ings into the combustion chamber along
with adequate accessibility clearance for
servicing and proper operation.
16. Do not install replace directly on carpet-
ing, vinyl tile or any combustible material
other than wood. The replace must set
on a metal or wood panel extending the
full width and depth of the replace.
17. Do not use replace if any part has been
exposed to or under water. Immediately
call a qualied service person to arrange
for replacement of the unit.
18. Do not operate fireplace if any log is
broken.
19. Do not use a blower insert, heat exchang-
er insert or other accessory not approved
for use with this replace.
20. Provide adequate clearances around air
openings.
UNPACKING
The following items are packed inside the
rebox. Remove before positioning rebox
into framing.
• Transition Collar - For vent connection
• Ceramic Log Pack - Shrink-wrapped on
cardboard
• Three (3) plastic bags containing lava rock,
pan and ember materials
• Rear Log - Remove the two plastic quick
ties from around the burner and grate
• Grate Stand - Lift off of burner pan
Check all items for any shipping damage. If
damaged, promptly inform dealer or distributor
where you bought the product.
Safely retain these items for later installation.
Models M36(P)(B,H), VM36(P)(B,H),
M42(P)(B,H) and VM42(P)(B,H) are vented
gas replaces that use a millivolt gas control
valve with a millivolt ignition system. A 6" B-
Type venting system and a listed type vent cap
are not supplied but are required for proper
operation. See venting instructions on pages
9 and 10.
WARNING: This gas appli-
ancemustnotbeconnectedto
achimneyueservicingasolid
fuelburningappliance.
BEFORE YOU BEGIN
Before beginning the installation of your
appliance, read these instructions through
completely.
This DESA Heating, LLC appliance and its
approved components are safe when installed
according to this installation manual and are
operated as recommended by DESA Heating,
LLC. Unless you use DESA Heating, LLC ap-
proved components tested for this appliance,
YOUMAYCAUSEAFIREHAZARD!
The DESA Heating, LLC warranty will be
voided by and DESA Heating, LLC disclaims
any responsibility for the following actions :
A) Modication of the appliance or any of the
components.
B) Use of any component part not approved
by DESA Heating, LLC in combination
with this appliance.
C) Installation and/or operation in a manner
other than instructed in this manual.
D) Burning of anything other than the type of
gas approved for use in this gas appliance.

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108795-01V 5
The installation must conform with local codes
or, in the absence of local codes, with the cur-
rent National Fuel Gas Code, ANSI Z223.1/
NFPA 54. This appliance complies with ANSI
Z21.50/CSA 2.22.
WARNING: Installation of
thisapplianceshould bedone
by a qualied service person
well trained in the installation
of such appliances. You will
alsoneedabuildingpermitfrom
your local Building and Safety
Commissionerbeforeinstalling
this appliance; otherwise your
insuranceco.maynotcoverthis
appliance.
NOTICE: This appliance is not
intendedtobeusedasaprimary
source of heat.
INTRODUCTION
Continued
Figure 1 - Possible Locations for
Installing Appliance
INTERNAL WALL
INSTALLATION
CORNER
INSTALLATION
FULL
PROJECTION
INSTALLATION
FLUSH
INSTALLATION
CAUTION: Do not connect
appliancebeforepressuretest-
inggaspiping.Damagetogas
valvemayresultandanunsafe
conditionmaybecaused.
The appliance and it’s individual shutoff valve
must be disconnected from gas supply piping
system during any pressure testing of that
system at test pressures in excess of 1/2
psig (3.5 kPa).
The appliance must be isolated from the gas
supply piping system by closing its individual
manual shutoff valve during any pressure testing
of the gas supply piping system at test pressures
equal to or less than 1/2 psig (3.5 kPa).
For the purpose of input adjustment two
pressure taps (for IN and OUT pressures)
are provided on the gas control valve for test
gauge connections to the appliance.
Flush installations are recommended where
living space is limited or at a premium and
since the space required to enclose the ap-
pliance would be located beyond an outside
wall, this would also reduce the cutting of
joists, roof rafters and such. Check local
codes for any restrictions.
Projected installations can extend any
distance into the room. A projection may
be ideal for a new addition on an existing,
nished wall.
Corner installations make use of space
that may not normally be used and provides
a wider and more efcient range for radiant
heat transference.
Internalwallinstallations provide a discreet
option for room separation and can also be
ideal as an addition to an existing wall.
SELECTING LOCATION
To determine the safest and most efcient
location for your appliance, you must take into
consideration the following guidelines:
1. The location must allow for proper clear-
ances (see Clearances, page 7).
2. Consider a location where heat output
would not be affected by drafts, air con-
ditioning ducts, windows or doors.
3. A location that avoids the cutting of joists
or roof rafters will make installation easier.
Figure 1 shows a plan view of a few com-
mon locations.

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PRODUCT SPECIFICATIONS
GAS RATING - NATURAL
M36(B,H),VM36(B,H) M42(B,H),VM42(B,H)
Max. Input Rating: 40,000 Btu/Hr 45,000 Btu/Hr
Manifold Pressure: 3.5" WC (.87 kPa) 3.5" WC (.87 kPa)
Minimum Supply Pressure: 4.5" WC (1.12 kPa) 4.5" WC (1.12 kPa)
Maximum Supply Pressure: 10.5" WC (2.66 kPa) 10.5" WC (2.66 kPa)
Orice Size: # 30 # 29
GAS RATING - PROPANE/LP
M36P(B,H),VM36P(B,H) M42P(B,H),VM42P(B,H)
Max. Input Rating: 40,000 Btu/Hr 45,000 Btu/Hr
Manifold Pressure: 10" WC (2.49 kPa) 10" WC (2.49 kPa)
Minimum Supply Pressure: 11" WC (2.74 kPa) 11" WC (2.74 kPa)
Maximum Supply Pressure: 13" WC (3.23 kPa) 13" WC (3.23 kPa)
Orice Size: # 52 # 51
S
T
P
Q
R
X
Outside Air
Kit Location
(Optional)
K
7"
J
I
M
LV
13.5"
1.5"
Glass Door
(Optional)
W
O
N
Alternate Gas
Supply Inlet
7"
G
H
F
A
Stand Off
Collar
For Use With
6"Ø Type B-1
Ve nt Pipe Only
B
E
D
C
DIMENSIONS
HEARTH AREA
7"
Figure 2 - Appliance Dimensions
Model 36 Model 42 Model 36 Model 42 Model 36 Model 42
A 29" 36" I 40 1/4" 44 1/4" Q 13 7/8" 14"
B5/8" 5/8" J 21" 24" R 10 1/2" 12 1/2"
C 41" 48" K 8" 9" S 2 1/2" 2 1/2"
D 12" 14" L 34 3/4" 42" T 8 1/8" 8 1/8"
E 21 1/4" 23" M 42" 49" U 11" 12 3/4"
F 22 1/4" (24" w/o Brick) 29 1/4" (31" w/o Brick) N 36" 40" V 7" 7"
G32 5/8" (34" w/o Brick) 39 1/2" (41 1/4" w/o Brick) O 37" 41" W 2 1/4" 2 1/4"
H 15 3/4" (16 3/4" w/o Brick) 17 3/4" (18 3/4" w/o Brick) P 8 5/8" 10 1/2" X 5" 4 1/2"

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108795-01V 7
PRE-INSTALLATION PREPARATION
Figure 3 - Minimum Clearances
(Top View)
0"
0" Clearance
Nailing
Flange
Front Face
Left Side
Surround
Back
Drywall
2 x 4 Stud
Figure 4 - Minimum Clearances
(Front View)
** **
42" (106.7 cm)
Min. Clearance
from Opening to
Ceiling 0" Clearance
Ceiling
1" (2.5 cm)
Min. Clearance
to "B" Vent's
Outer Pipe
Maintain 2" (5.1 cm)
Min. Clearance to
Transition Pipe as
Measured at Outer
Ve nt Collar
Required air
spaces are
indicated with
an "
*
". Do not
pack with
insulation or
any other
material.
DO NOT BLOCK
OR OBSTRUCT
OPENINGS
0" Clearance to
Combustible or
Noncombustible
Flooring
MANTEL CLEARANCES AND WALL
DETAILS
A combustible mantle shelf maybe installed
a maximum 12" (22.9 cm) from the wall.
Figures 5 and 6 show the minimum allow-
able distances from various combustible
mantle components in relation to fireplace
opening.
Spacer
3" (7.6 cm)
1
1
/
2
"
(3.8 cm) Max.
B
6" (15.2 cm)
A
12"
(22.9 cm)
Combustible
Materials
Header
Figure 5 - Mantel Clearances - Side View
(Cross Section)
M36(B,H),
M36P(B,H)
VM36(B,H),
VM36P(B,H)
M42(B,H),
M42P(B,H)
VM42(B,H),
VM42P(B,H)
A14" (35.6 cm) 15" (38 cm)
B 8" (20.3 cm) 9" (22.9 cm)
1
1
/
2
"
(3.8 cm)
Max. 3" (7.6 cm)
Max.
6" (15.2 cm)
Max. A
B
Outer Surround Combustible
Material May
Be Used
TOP VIEW
SAFE
ZONE
Perpendicular
Wall
Figure 6 - Side Clearances - Top View
(Cross Section)
CLEARANCES
Minimum clearances to combustibles are:
Back and Sides of Outer Surround 0" min.
Drywall to Sides of Front Face
(Nailing Flanges) 0" min.
“B” Vent Surfaces 1" min.
Ceiling to Opening 42" min.
Floor 0" min.
Perpendicular Wall See Figure 6
 CAUTION: Do not block
required air spaces with insu-
lationoranyothermaterial.Do
not obstruct effective opening
of appliance with any type of
facingmaterial.
M36(B,H),
M36P(B,H)
VM36(B,H),
VM36P(B,H)
M42(B,H),
M42P(B,H)
VM42(B,H),
VM42P(B,H)
A9" (22.9 cm) 6" (15.2 cm)
B 12" (30.5 cm) 9" (22.9 cm)

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PRE-INSTALLATION PREPARATION
Continued
FRAMING
1. Frame appliance enclosure as illustrated
in Figures 7 and 8.
Note: If a wall covering is used to line the
enclosure, then all measurements must
be from the surface of the covering.
2. Place the appliance into the framing and
secure it.
Note: If appliance is to be raised above
oor level, a platform must be built to
support the appliance.
3. Install the supply line to the appliance
using a 1/2" NPT black iron gas line ter-
minating 2 5/16" above the bottom of the
appliance. The gas line must be installed
through the lower left side access point or
alternate access hole in the bottom of the
appliance (see Figure 19, page 13).
4. Repack insulation around the gas line to
cover any remaining openings in the con-
duit sleeve. Prepare the incoming gas line
with teon tape or pipe joint compound
and hook-up incoming gas line to the
exible gas line.
Note: If 1/2" NPT black iron pipe does not
mate with tting at the end of exible gas
line, remove tting and replace with a 37°
are 3/4"-12, 1/2" NPT (female) tting.
 WARNING: When nishing
appliance,donotoverlapcom-
bustiblematerialontotheblack
front face. Brick, tile or other
noncombustiblematerialsmay
beappliedtothefaceprovided
that any gap is between the
material used and the face is
caulkedwithanoncombustible
caulking.
Figure 7 - Rough Opening for Installing
in Wall
B
C
A
M36(B,H),
M36P(B,H)
VM36(B,H),
VM36P(B,H)
M42(B,H),
M42P(B,H)
VM42(B,H),
VM42P(B,H)
A 40 3/8" (102 cm) 44 3/8" (112 cm)
B21 3/8" (54.3 cm) 23 1/8" (58.7 cm)
C 41 1/4" (104.8 cm) 48 1/4" (122.6 cm)
Figure 8 - Corner Installation Guidelines
A
B
C
D
M36(B,H),
M36P(B,H)
VM36(B,H),
VM36P(B,H)
M42(B,H),
M42P(B,H)
VM42(B,H),
VM42P(B,H)
A 24 1/2" (62.2 cm) 27 9/16" (70 cm)
B73 7/8" (187.6 cm) 83 7/8" (213 cm)
C 52 3/16" (132.6 cm) 59 5/16" (150.6 cm)
D 17 1/4" (43.8 cm) 19 1/2" (49.5 cm)
These Dimensions Allow for a 3/4"
Clearance at Sides and Back of Fireplace.
However, 0" Clearance is Permitted.
3/4" Clearance Not Required
at Nailing Flanges

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108795-01V 9
INSTALLING TRANSITION PIPE AND
STARTER COLLAR
The transition pipe and starter collar shown
in Figure 9 are supplied with the replace,
unattached and ready for installation. Re-
move starter collar and set aside. Slide
transition pipe over vent collar and attach
with a minimum of three screws. Replace
starter collar over transition pipe and attach
using four screws located on leg stands (ve
used on model M42). To install B-vent piping,
slide the rst piece of B-vent over transition
pipe and attach with either a minimum of two
screws or other means approved by the vent
manufacturer. Figure 9 - Installing Transition Pipe and
Starter Collar
B-Vent Piping
Transition Pipe
Starter Collar
Vent Collar
PRE-INSTALLATION PREPARATION
Continued
VENTING INSTALLATION
60° or greater. The total vertical height in this
example represents the minimum height of 8
feet and therefore the allowable lateral is 6
feet when the 75% rule applies. If the lateral
length must exceed 75% then the system
must be sized in accordance with Category I
venting tables.
Example2: Shows a multiple offset each at
45° of inclination. Multiple offsets are permit-
ted if they do not exceed 45° of inclination. The
total lengths of the two offsets are not required
to meet the 75% allowable rule.
Example3:Shows a single offset at 45° of
inclination and therefore the lateral length at
10 feet of offset does not have to meet the
75% rule.
In each case the offsets must be supported
and restops must be positioned wherever
the vent must pass through a sub-oor, ceil-
ing joist or an attic overhang. The vent pipe
must terminate vertically into a listed type vent
cap and extend a sufcient height through
an approved roof ashing, roof jack or a roof
thimble. At all points listed clearances must
be maintained.
Vent terminations must be located in ac-
cordance with height and proximity rules of
NFPA No. 54. These rules apply to vents at
12" diameter or less and require a minimum
height in accordance with the roof pitch and a
minimum of 8 ft. distance from a vertical wall
or obstruction (see Figure 11, page 10).
A B-type venting system must be connected
to the appliance for venting to the outside of
the building.
The following section is provided as a guide
to a standard B-type vent installation.
Standing codes requirements concerning B-
type vent installations may vary within your
state, province or local codes jurisdiction.
Therefore, it is recommended that you check
with your local building codes for specic
requirements or in absence of local codes,
follow Section 7.0 of the current National Fuel
Gas Code ANSI Z223.1/NFPA 54.
This gas appliance must be vented to the
outdoors only and may not be terminated into
an attic space or into a chimney ue servicing
a solid fuel burning appliance.
This appliance may be vented through a
manufactured chimney system or a masonry
chimney using a B-vent adapter or a chim-
ney liner system if all are listed, inspected
and approved by local codes and/or building
authorities.
The examples shown in Figure 10, page 10
are typical of most B-vent installations and
codes practices.
Example1: Shows the minimum allowable
system height and lateral offset for a 60° or
greater inclination. Code species that offsets
at 60° or greater are considered horizontal
and must follow the 75% rule for lateral to
total vertical system height. Codes also allow
only one offset in the total system when at

www.desatech.com 108795-01V10
Maintain
Listed
Clearance
Maintain
Listed
Clearance
12' Min.
12' Min. 45°
45°
6'
8'
12' Min.
60° 45°
Position
Firestop
Position
Firestop
Position
Firestop
Listed
Vent Cap
Listed
Vent Cap
Listed
Vent Cap
Maintain
Listed
Clearance
Maintain
Listed
Clearance
Maintain
Listed
Clearance
Maintain
Listed
Clearance
Support Each
Lateral At
Least Every
6 Feet
Maintain
Listed
Clearance
10'
EXAMPLE 3EXAMPLE 2
EXAMPLE 1
Figure 10 - Typical B-Vent Conguration
VENTING INSTALLATION
Continued
Some codes areas allow the use of existing
B-type vent systems if the system is at or
above the recommended diameter of the ue,
in this case 6".
The ue connection must be made using
listed B-type connectors and the existing
system must be code inspected for damage
and proper installation.
It is not recommended that this appliance be
common vented with an existing gas burning
appliance.
Note: Before connecting this appliance to an
existing vent system consult with your local
architect, planner or building ofcial.
WARNING: This appliance
must be properly connected
to a system and must not be
connected to a chimney ue
servicing a separate solid fuel
burningappliance.
Lowest
Discharge
Opening
Listed
Ve nt Cap
8 Ft. Min.
Roof Pitch x/12
Listed Clearance
12
x
Listed
Gas
Ve nt
H (Min)
Height
From Roof
Roof Pitch
H(Min.)
Feet Meter
Flat to 6/12 1.0 ax 0.30
6/12 to 7/12 1.25 0.38
Over 7/12 to 8/12 1.5 0.46
Over 8/12 to 9/12 2.0 0.61
Over 9/12 to 10/12 2.5 0.76
Over 10/12 to 11/12 3.25 0.99
Over 11/12 to 12/12 4.0 1.22
Over 12/12 to 14/12 5.0 1.52
Over 14/12 to 16/12 6.0 1.83
Over 16/12 to 18/12 7.0 2.13
Over 18/12 to 20/12 7.5 2.27
Over 20/12 to 21/12 8.0 2.44
Figure 11 - B-Vent Terminations