Osburn 1100 User manual

READ AND KEEP THIS MANUAL FOR REFERENCE
45127A
Printed in Canada 20-02-2012
OWNER`S MANUAL
1100 MODEL STOVE
US ENVIRONMENTAL PROTECTION AGENCY PHASE II CERTIFIED WOODSTOVE

STOVE BUILDER INTERNATIONAL INC.
250, de Copenhague,
Saint-Augustin-de-Desmaures
(Quebec), Canada G3A 2H3
Tel: [phone]
Fax: [phone]
Verified and tested following
ULC S627 and UL 1482 Standards by:
www.osburn-mfg.com
This manual is available for free download onthe manufacturer’sweb site. It is a copyrighted
document. Re-sale is strictly prohibited. The manufacturer may update thismanual from time
to time and cannot be responsible for problems, injuries, or damages arising out of the use of
information contained in any manual obtained from unauthorized sources.

2
INTRODUCTION
SBI INC., one of the most important wood stove and fireplace manufacturers in Canada,
congratulates you on your purchase and wishes to help you get maximum satisfaction from your wood
stove. In the pages that follow, we will give you advice on wood heating and controlled combustion as
well as technical specifications regarding installation, operation and maintenance of the model you
have chosen.
The instructions pertaining to the installation of your wood stove comply with ULC-S627 and UL-1482
standards.
We recommend that our wood burning hearth products be installed and serviced by professionals who
are certified in the United States by NFI (National Fireplace Institute®) or in Canada by WETT (Wood
Energy Technical Training) or in Quebec by APC (Association des Professionnels du Chauffage).
Read this entire manual before you install and use your new stove. If this stove is not properly
installed, a house fire may result. To reduce the risk of fire, follow the installation instructions.
Failure to follow instructions may result in property damage, bodily injury, or even death.
Consult your municipal building department or fire officials about restrictions and installations
requirements in your area and the need to obtain a permit.
Keep this instructions manual for future references.
CAUTIONS:
THE INFORMATION GIVEN ON THE CERTIFICATION LABEL AFFIXED TO THE APPLIANCE ALWAYS OVERRIDES THE
INFORMATION PUBLISHED,IN ANY OTHER MEDIA (OWNER’S MANUAL,CATALOGUES,FLYERS,MAGAZINES
AND/OR WEB SITES).
HOT WHILE IN OPERATION.KEEP CHILDREN,CLOTHING AND FURNITURE AWAY.CONTACT MAY CAUSE SKIN
BURNS.
DO NOT USE CHEMICALS OR FLUIDS TO IGNITE THE FIRE.
DO NOT LEAVE THE STOVE UNATTENDED WHEN THE DOOR IS SLIGHTLY OPENED.
DO NOT BURN WASTES,FLAMMABLE FLUID SUCH AS GASOLINE,NAPHTHA OR MOTOR OIL.
DO NOT CONNECT TO ANY AIR DISTRIBUTION DUCT OR SYSTEM.
ALWAYS CLOSE THE DOOR AFTER THE IGNITION.
REGISTER YOU WARRANTY ONLINE
To receive full warranty coverage, you will need to show evidence of the
date you purchased your stove. Keep your sales invoice. We also
recommend that you register your warranty online at
www.osburn-mfg.com/warranty-registration.aspx
Registering your warranty online will help us track rapidly the information
we need on your stove

3
TABLE OF CONTENTS
INTRODUCTION............................................................................................................................................ 2
OVERALL STOVE DIMENSIONS.................................................................................................... 4
INSTALLATION REQUIREMENTS............................................................................................................ 5
RESIDENTIAL INSTALLATION INSTRUCTIONS ......................................................................................... 5
MANUFACTURED (MOBILE)HOME INSTALLATIONS –ADDITIONAL REQUIREMENTS ............................ 6
INSTALLATION............................................................................................................................................. 7
GENERAL INSTALLATION ....................................................................................................................... 7
DOOR OVERLAY INSTALLATION ............................................................................................................. 8
CLEARANCES TO COMBUSTIBLES AND FLOOR PROTECTOR ................................................................ 9
CHIMNEY SYSTEM..................................................................................................................................... 16
DEFINITIONS ........................................................................................................................................ 16
COMPONENTS ..................................................................................................................................... 16
FACTORY BUILT CHIMNEY SYSTEM .................................................................................................... 16
RESIDENTIAL CLOSE CLEARANCES CHIMNEY SYSTEM ...................................................................... 17
GENERAL INSTALLATION REQUIREMENTS .......................................................................................... 17
CHIMNEY CONNECTOR........................................................................................................................ 17
CHIMNEY SYSTEMS ............................................................................................................................. 19
EXTERIOR CHIMNEY ............................................................................................................................ 20
DRAFT.................................................................................................................................................. 20
TYPICAL TYPES OF CHIMNEY SYSTEMS ............................................................................................. 21
FIGURE 1.9 CONNECTION TO A FACTORY BUILT CHIMNEY (EXTERIOR
SHOWN)OPERATION................................................................................................................................ 22
OPERATION................................................................................................................................................. 23
SAFETY INFORMATION......................................................................................................................... 23
FUEL .................................................................................................................................................... 24
SIMPLE WOOD MOISTURE TEST ......................................................................................................... 25
NOTES ABOUT FIRST FIRING .............................................................................................................. 25
LIGHTING AFIRE ................................................................................................................................. 25
MAINTAINING THE FIRE ....................................................................................................................... 27
(OPTIONAL)FAN INSTALLATION AND OPERATION .............................................................................. 28
MAINTENANCE........................................................................................................................................... 29
CARE AND CLEANING.......................................................................................................................... 29
GLASS CLEANING ................................................................................................................................ 29
ASH REMOVAL USING ASH DRAWER.................................................................................................. 29
CHIMNEY CLEANING ............................................................................................................................ 31
BAFFLE INSTALLATION AND BRICK NOTES.......................................................................................... 32
BRICK LAYOUT..................................................................................................................................... 33
SECONDARY AIR TUBE REPLACEMENT .............................................................................................. 33
TROUBLESHOOTING................................................................................................................................ 34
SPECIFICATIONS....................................................................................................................................... 35
OSBURN LIMITED LIFETIME WARRANTY .......................................................................................... 36

4
OVERALL STOVE DIMENSIONS
Figure 1

5
INSTALLATION REQUIREMENTS
In Canada the CSA B365 Installation Code for Solid Fuel Burning Appliances and Equipment and
the CSA C22.1 Canadian National Electrical Code are to be followed in the absence of local code
requirements. In the USA the ANSI NFPA 70 National Electrical Code and NFPA 211 Standard
for Chimneys, Fireplaces, Vents and Solid Fuel-Burning Appliances are to be followed in the
absence of local code requirements.
In addition to the national installation codes, local building and/or fire officials (or otherauthorities
having jurisdiction) should be contacted to determine what restrictions and installation
requirements might locally apply.
When installed and operated as described in these instructions, the 1100 is intended to be
used as the following:
 as a residential freestanding stove with vertical or horizontal connector.
 in a mobile home*.
 in an alcove.
 as a Hearth mount stove for masonry or zero clearance fireplaces.
The 1100 is not intended for installation in a sleeping room.
* The 1100 wood stove is ‘mobile home approved’ only with the pedestal option and with
optional OA10500 and AC02090.
RESIDENTIAL INSTALLATION INSTRUCTIONS
Choose a location for the unit which meets the minimum clearances to combustibles (see Figure
1.3). For other than masonry chimneys determine if the factory built chimney will pass between
the ceiling joists; if not, choose a new location so that it will, while still maintaining the minimum
clearances.
Mark the location for the floor protection (if required) as noted in Figure 1.3.
Note: If outside air for combustion is to be used it should be provided for at this time. This
requires that the Osburn Fresh Air Kit Wood (#OA10500) be installed (refer to the installation
instructions which are provided in the outside air kit). Install the unit.

6
MANUFACTURED (MOBILE) HOME INSTALLATIONS – ADDITIONAL
REQUIREMENTS
1. The stove must be bolted to the floor (secure the unit by prying out the two plastic
plugs in the pedestal, and installing the two 3/8" x 3-1/2" (9.8mm x 88.9mm) lag bolts
through the holes provided).
2. The unit
must be provided with outside combustion air.
3. Clearance from the top of stove to an unprotected ceiling should be a minimum of 52”
(1321mm).
4. The stove must be used connected to the chimney with listed double wall connector of
6" (152 mm) diameter.
5. The chimney system must be a minimum of 12' (3658 mm) in height from the hearth
pad to the top of the chimney assembly.
Figure1.1 Necessary installation components.
Note: For manufactured home installations in the USA, the stove must be grounded to the frame
of the home using a # 8 ground wire with approved terminations and star lock washers.
CAUTION: THE STRUCTURAL INTEGRITY OF THE MANUFACTURED HOME FLOOR,WALL,CEILING /ROOF
MUST BE MAINTAINED.
CAUTION:DO NOT INSTALL IN ASLEEPING ROOM.
TYPICAL MOBILE
HOME INSTALLATION
RAINCAP
FACTORY BUILT CHIMNEY
STORM COLLAR
ROOF FLASHING
SUPPORT/SHIELD
CHIMNEY ADAPTOR
DOUBLE WALL CONNECTOR
DOUBLE WALL 45° ELBOW
OSBURN 1100

7
INSTALLATION
When installed and operated as described in these instructions, the Osburn 2000 wood stove is
suitable for use as a freestanding wood stove in residential installations. The E.P.A Osburn wood
stove is not intended for installation in a bedroom.
In Canada, the CSA B365 Installation Code for Solid Fuel Burning Appliances and Equipment
and the CSA C22.1 Canadian National Electrical Code are to be followed in the absence of local
code requirements. In the USA, the ANSI NFPA 70 National Electrical Code and NFPA 211
Standard for Chimneys, Fireplaces, Vents and Solid Fuel-Burning Appliances are to be followed
in the absence of local code requirements.
In addition to the national installation and/or local building codes, fire officials (or other authorities
having jurisdiction) should be contacted to determine what restrictions and installation
requirements might apply locally.
GENERAL INSTALLATION
CAUTION:
MIXING OF APPLIANCE OR FLUE SYSTEM COMPONENTS FROM DIFFERENT SOURCES OR MODIFYING THE
DIMENSIONAL SPECIFICATION OF COMPONENTS MAY RESULT IN HAZARDOUS CONDITIONS.WHERE SUCH
ACTION IS CONSIDERED,THE MANUFACTURER SHOULD BE CONSULTED IN THE FIRST INSTANCE.
DO NOT CONNECT THIS UNIT TO ANY AIR DISTRIBUTION SYSTEM.
CRACKED AND BROKEN COMPONENTS,e.g. GLASS PANELS OR CERAMIC TILES,MAY RENDER THIS
INSTALLATION UNSAFE.
ASOURCE OF FRESH AIR INTO THE ROOM OR SPACE HEATED SHALL BE PROVIDED WHEN REQUIRED.
INSTALL A SMOKE DETECTOR IN THE ROOM WHERE THE STOVE IS LOCATED
CONNECT THE STOVE ONLY TO A LINED MASONRY CHIMNEY CONFORMING TO NATIONAL AND LOCAL BUILDING
CODES FOR USE WITH SOLID FUEL,OR TO A LISTED FACTORY BUILT CHIMNEY SUITABLE FOR USE WITH SOLID
FUEL.
This heating unit must serve as a supplementary heat source. An alternative heat source
should be available in the home if needed. The manufacturer cannot be responsible for
additional heating costs associated with the use of an alternative heat source.
It is highly recommended that the user buys this product from a retailer who can provide
installation and maintenance advices.

8
DOOR OVERLAY INSTALLATION
In order to complete the assembly of your freestanding Osburn 1100 wood stove, you need to
install the door overlay. See Figure 1.2 below for installation instructions :
1- Position the overlay on the door frame and fix it in place from behind using the 4
screws.
Note: It is not necessary to remove the glass or any other component to install the overlay.
Figure 1.2 Door overlay installation

9
CLEARANCES TO COMBUSTIBLES AND FLOOR PROTECTOR
To install your appliance correctly, it is extremely important to respect all clearances to any
combustibles as indicated on your stove’s certification label.
Clearances to combustible materials
(see figure 1.3 to match each letter to a clearance)
CLEARANCES (SINGLE WALL PIPE)
CANADA USA
A 20" (508 mm) 20" (508 mm)
B 16" (406 mm) 16" (406 mm)
C 14" (356 mm) 14" (356 mm)
D 21" (533 mm) 21" (533 mm)
E 25" (635 mm) 25" (635 mm)
F 19" (482 mm) 19" (482 mm)
K 48" (1220 mm) 48" (1220 mm)
L 84" (213 cm) 84" (213 cm)
CLEARANCES (DOUBLE WALL PIPE)
CANADA USA ALCOVE
CANADA / USA MOBILE HOME CANADA / USA
A 12" (305 mm) 12" (305 mm) 13" (330 mm) 12" (305 mm)
B 17" (432 mm) 17" (432 mm) 13" (330 mm) 17" (432 mm)
C 6" (152 mm) 6" (152 mm) - 6" (152 mm)
D 13" (330 mm) 13" (330 mm) 14" (356 mm) 13" (330 mm)
E 26" (660 mm) 26" (660 mm) 22" (559 mm) 26" (660 mm)
F 11" (279 mm) 11" (279 mm) - 11" (279 mm)
K 48" (1220 mm) 48" (1220 mm) 48" (1220 mm) 48" (1220 mm)
L 84" (213 cm) 84" (213 cm) 84" (213 cm) 84" (213 cm)

10
FIGURE 1.3 Clearances to combustible materials and floor protection

11
Floor protector
If the stove is to be installed on top of a combustible floor, it must be guarded by a non
combustible material as shown on figure 1.3 (see the dotted line area).
FLOOR PROTECTOR*
CANADA USA
G 8’’ (203 mm) – Note 1 N/A (Canada only)
H 8’’ (203 mm) N/A (Canada only)
I 18’’ (457 mm)
From door opening
16’’ (406 mm)
From door opening
J N/A (USA only) 8’’ (203 mm)
M 8’’ (203 mm) N/A (Canada only)
N N/A (USA only) Note 2
*Steel with a minimum thickness of 0.015’’ (0.38 mm) or ceramic tiles sealed together with
grout. No protection is required if the unit is installed on a non-combustible floor (ex:
concrete).
Note 1 : The floor protection at the back of the stove is limited to the stove’s required
clearance if such clearance is smaller than 8 inches (203 mm).
Note 2 : Only required under the horizontal section of the connector. Must exceed each
side of the connector by at least 2 inches (51 mm).
Reduced clearances using shielding
You may decrease the clearances by installing heat radiation shields between the walls or the
ceiling and the stove. These heat radiation shields must be installed permanently, and can
include sheet metal, a rigid non-combustible sheet or a masonry wall.
Clearances of not less than 1" (25 mm) and not more than 3" (76 mm) between the bottom of the
shield and the floor and not less than 3" (76 mm) between the top of the shield and the ceiling
must be respected to allow vertical air circulation behind the shield. The shield must extend 20"
(500 mm) above the stove top and 18" (450mm) to each side of the stove (see graphic 1).
Following the installation of such a heat radiation shield, the clearances mentioned on the stove
certification plate may be reduced as stated in the following table.

12
TYPE OF PROTECTION
Reducing Clearances
With Shielding
Sides and
Rear/Back Top
Sheet metal, a minimum of 0,024" (0,61mm) spaced out
at least 1" (25mm) by non-combustible spacers
(see graphic 2).
67% 50%
Ceramic tiles, or an equivalent non-combustible material
on fire-proof supports spaced out at least 1" (25 mm) by
non-combustible spacers (see graphic 3).
50% 33%
Ceramic tiles, or an equivalent non-combustible material
on fire-proof supports with a minimum of 0,024" (0,61
mm) sheet metal backing spaced out at least 1" (25 mm)
by non-combustible spacers (see graphic 4)
67% 50%
Brick spaced out at least 1" (25 mm) by non-combustible
spacers (see graphic 5) 50% N/A
Brick with a minimum of 0,024" (0,61 mm) sheet metal
backing spaced out at least 1" (25 mm) by non-
combustible spacers (see graphic 6).
67% N/A

13
Graphic 1
A- Minimum clearance required between the appliance and an unshielded combustible
ceiling.
B- 20 in. (500 mm) minimum;
C- 1 in. (25 mm) minimum;
D- Between 1 in. and 3 in. (25 mm and 75 mm);
E- 3 in.(75 mm) minimum;
F- 18 in. (457 mm) minimum.
1- Shielding;
2- Non-combustible spacers;
3- Ceiling protector;
4- Combustible wall;
5- Ceiling;
6- Appliance (side view);
7- Appliance (top view).

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Graphic 2
A- 1 in.(25 mm) minimum;
1- Combustible wall;
2- Non-combustible spacers;
3- 0.024’’ (0.61mm) sheet metal.
Graphic 3
A- 1 in. (25 mm) minimum;
1- Combustible wall;
2- Non-combustible spacers;
3- Non-combustible support;
4- Ceramic tile or non-combustible material.
Graphic 4
A- 1 in. (25 mm) minimum;
1- Combustible wall;
2- Non-combustible spacer;
3- 0.024’’ (0.61 mm) thick sheet metal;
4- Non-combustible support;
5- Ceramic tile or non-combustible material.

15
Graphic 5
A- 1 in. (25 mm) minimum;
1- Combustible wall;
2- Non-combustible spacers;
3- Brick.
Graphique 6
A- 1 in. (25 mm) minimum;
1- Combustible wall;
2- Non-combustible spacers;
3- 0.024’’ (0.61 mm) thick sheet metal;
4- Brick.

16
CHIMNEY SYSTEM
DEFINITIONS
For clarity, the following definitions should be used with respect to these instructions:
A chimney system consists of the connector off the top of the stove, and a chimney, which
joins to the connector and terminates outside the building envelope.
A chimney can be a masonry chimney (of masonry construction with an inside liner), or a
factory built chimney.
A factory built chimney can be a double walled chimney (two concentric pipes with
insulation sometimes referred to as an insulated solid pack, or an air cooled chimney
(three concentric pipes, with insulation between the first and second pipes, and air
between the second and third pipes).
A single walled connector is a single pipe.
A double walled connector has two concentric pipes, no insulation, and is an air cooled
connector.
COMPONENTS
NOTE:All connector and manufactured chimney components must be LISTED COMPONENTS.
Masonry Chimneys must be Code Complying, and have a listed solid fuel burning liner (of
stainless steel or clay refractory construction).
FACTORY BUILT CHIMNEY SYSTEM
The following are the generic components required for a factory built chimney system for
residential installations:
Chimney – in the USA use a 6” diameter (152 mm) listed UL 103 HT chimney system and
components
Chimney – in Canada use 6” diameter (152 mm) listed ULC S629 chimney system and
components
MANUFACTURED (MOBILE)HOME CHIMNEY SYSTEM
In addition to the requirements of section 1.6.2 the following components are required for
manufactured (mobile) home installations:
A spark arrestor must be employed with the rain cap
Double walled connectors must be used instead of single walled connectors
For manufactured (mobile) home installations in the USA only and where the chimney
system has employed a solid pack chimney, a vented roof flashing must also be used.

17
RESIDENTIAL CLOSE CLEARANCES CHIMNEY SYSTEM
In addition to the requirements of section 1.6.2.1 the following components are required
for residential close clearances installations:
Double walled connectors must be used instead of single walled connectors
GENERAL INSTALLATION REQUIREMENTS
CAUTION:DO NOT FILL ANY FRAMED SPACE AROUND THE FACTORY-BUILT CHIMNEY WITH
INSULATION OR ANY OTHER MATERIAL.INSULATION PLACED IN THIS AREA COULD CAUSE ADJACENT
COMBUSTIBLES TO OVERHEAT.
DO NOT USE MAKESHIFT COMPROMISES DURING INSTALLATION AS THEY MAY BE SAFETY HAZARDS,
AND AFIRE COULD RESULT.
DO NOT CONNECT THIS UNIT TO ACHIMNEY SYSTEM SERVING ANOTHER APPLIANCE.
DO NOT CUT RAFTERS OR CEILING JOISTS WITHOUT FIRST CONSULTING ABUILDING OFFICIAL TO
ENSURE STRUCTURAL INTEGRITY IS NOT COMPROMISED.
CHIMNEY CONNECTOR
Your chimney connector (commonly called stove pipe) and chimney must have the same
diameter as the stove’s exhaust outlet. The stove pipe must be made of aluminized or cold roll
steel with a minimum 24-gauge thickness (0.021" or 0.53 mm). It is strictly forbidden to use
galvanized steel.
The following recommendations may be useful for the installation of your chimney connector:
Your chimney connector should be assembled in such a way that the male end (crimped)
faces down to prevent creosote dripping outside the joints. Attach each of the sections to
one another with three equidistant metal screws. Also use three equidistant metal screws
to attach the connector to the stove’s exhaust collar. See Figure 2.3 (A) and Figure 2.3
(B).
The pipe must be short and straight. All sections installed horizontally must slope at least
¼ inch per foot, with the upper end of the section toward the chimney. See Figure 2.3
Detail B.
To insure a good draft, the total horizontal length of the connector should never exceed 8'
to 10' (2.4 to 3.04 m). In the case of vertical installation, the total length of the connector
can be much longer and connected without problem to the chimney at the ceiling level.
There should never be more than two 90 degrees elbows in the whole connector and
chimney system. Never start with a 90oelbow. Always go up vertically for at least 2 feet
from the flue spigot before using a 90oelbow.

18
The connector must not pass through any combustible material, nor may it pass through a
concealed space (such as an attic, roof space, or closet). If passing through a wall, ceiling,
or into a masonry chimney, use either chimney components listed for that specific use, or
means acceptable to local authorities having jurisdiction over the installation.
Installation of a "barometric draft stabiliser" (fireplace register) on a connector is not
recommended.
FIGURE 2.3 (A) Connecting Sections
FIGURE 2.3 (B) Minimum Slope

19
The assembly should be as short and direct as possible between the stove and chimney
(See figure 2.4 (A)). The use of two 45 degree elbows (See figure 2.4 (C)) is often
preferable to a single 90 degree elbow (See figure 2.4 (B)) because less turbulence is
created in the exhaust flow and they result in less horizontal run.
(A) (B) (C)
FIGURE 2.4 The use of elbows
CHIMNEY SYSTEMS
The minimum chimney size is 6" (152 mm) in diameter. The minimum overall height of the
chimney system, measured from the base of the appliance is 12' (3.66m). Existing masonry and
metal chimneys should be inspected to check for deterioration and to determine if they meet the
minimum installation requirements; they should be upgraded if necessary. In Canada, masonry
chimneys must have or use a ULC S635 listed Class III liner in chimney systems that are not
ULC S629 listed. Similarly in the USA a UL 1777 listed refractory or metallic liner must be used.
At the point of penetration through the roof to the outside of the building envelope, the chimney
must extend at least 3' (914 mm) above the roof and at least 2' (610 mm) above the highest point
within an area of 10' (3 m) of the chimney (see Figure 1.6).
Follow CSA Standard B365-M91 for methods and precautions to be employed when connecting
the stove to a masonry chimney, and for installing thimbles (wall penetration assemblies) when
the connection from the stove to the masonry chimney is made through a combustible wall.
When connecting to a factory built chimney, ensure that it is installed according to the
manufacturer's listed instructions. If using an existing chimney, inspect and clean the chimney if
required (this should be done by a licensed chimney sweep or a qualified professional).

20
Figure 1.6 – Chimney height
EXTERIOR CHIMNEY
Chimneys constructed outside of the home on an exterior wall should be avoided if possible,
especially in colder climates. Exterior chimneys may not draft well and in fact may down draft
(reverse flow) due to the difficulty in heating them up to operating temperature while trying to
evacuate the stack gases. All else being equal, cooler chimneys will have less draft than hotter
ones; this may lead to creosoting and poor performance. If an exterior chimney is used to remove
the stack gases the best results will be obtained by using a connector vertically off the unit to the
highest possible point before elbowing off horizontally to the chimney. For efficiency and safety
reasons the stove must not be installed with an insulated chimney connected directly to the
appliance.
DRAFT
Your E.P.A Drolet stove’s performance will be optimised if it is installed with a chimney (flue)
system that provides an adequate draft. The draft is the force that moves air from the appliance
up through the chimney and is predominantly affected by the height and diameter of the chimney,
as well as the stack temperatures of the stove. If you test the draft using a pressure gauge, the
reading should be between .05 - .07 inches of water column (w.c.) at a medium-high fire. A draft
measure of less than .03" w.c. will cause operational difficulties while too much draft (greater than
.10" w.c.) will result in over-firing of the stove. This can result in excessive operating
temperatures. In this case, the installation of elbows totaling no more than 180° (ex.: 2 x 30°
elbows, 2 x 45° elbows or 2 x 90° elbows) can be installed to help reduce excessive draft. If the
addition of elbows is not sufficient, a manual damper can be installed in the vertical flue pipe.