SUPREME Astra 24 User manual

Astra 24
Owner’s Manual
Model Number: 24SFC
This product is proudly manufactured in North America by SUPREME FIREPLACES INC.
3594 Jarry East, Montreal, QC H1Z 2G4
T: 877-593-4722, F: 514-593-4424
www.supremem.com
Revised: July 2020
IMPORTANT: Keep the owner’s manual for future use.

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CONTENTS
1SAFETY ......................................................................................................................................................1
2GENERAL INFORMATION..........................................................................................................................2
2.1 Overall Dimensions.............................................................................................................................2
2.2 Specifications......................................................................................................................................3
2.3 Combustion Air Control .......................................................................................................................4
2.4 Cold Hand Key....................................................................................................................................4
2.5 Chimney Sweeping Cap......................................................................................................................4
2.6 Door....................................................................................................................................................4
2.7 Certification Label................................................................................................................................5
2.8 Removable Ash Lip.............................................................................................................................5
2.9 Blower Kit............................................................................................................................................6
2.10 Optional Hot Air Kit..............................................................................................................................6
2.11 Optional Fresh Air Kit ..........................................................................................................................6
3INSTALLATION INSTRUCTIONS................................................................................................................7
3.1 Location...............................................................................................................................................7
3.2 Chimney Installation............................................................................................................................8
3.2.1 General Rules and Guidelines......................................................................................................8
3.2.2 Listed UL 103 / ULC S629 Approved Chimney Models (Reference Table)...................................9
3.2.3 Chimney Installation Instructions..................................................................................................9
3.2.4 Offset Installation........................................................................................................................10
3.2.5 Angled Wall Radiation Shield .....................................................................................................10
3.2.6 Connecting to a Masonry Chimney.............................................................................................10
3.3 Surround Installation..........................................................................................................................12
3.3.1 Traditional Surround...................................................................................................................12
3.3.2 Clean Face Surround.................................................................................................................13
3.4 Gravity Kit Installation........................................................................................................................15
3.5 Framing.............................................................................................................................................17
3.6 Hearth Extension...............................................................................................................................17
3.6.1 Calculating R-Value....................................................................................................................18

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3.7 Chase Installation..............................................................................................................................19
3.8 Clearances to Combustibles..............................................................................................................20
3.9 Blower Kit..........................................................................................................................................21
4 OPTIONS..................................................................................................................................................23
4.1 Hot Air Kit..........................................................................................................................................23
4.2 Fresh Air Kit ......................................................................................................................................24
5OPERATION INSTRUCTIONS..................................................................................................................26
5.1 Fuel...................................................................................................................................................26
5.2 First Fires..........................................................................................................................................26
5.3 Operating the Combustion Air Control...............................................................................................26
5.4 Starting a Fire....................................................................................................................................27
5.5 Adding a New Load of Wood.............................................................................................................28
5.6 Blower Operation...............................................................................................................................28
6TROUBLESHOOTING...............................................................................................................................29
6.1 Backdraft / Smoking ..........................................................................................................................29
6.2 Over Firing ........................................................................................................................................29
7MAINTENANCE.........................................................................................................................................30
7.1 Disposal of Ashes..............................................................................................................................30
7.2 Chimney Maintenance.......................................................................................................................30
7.3 Cleaning of Glass..............................................................................................................................31
7.4 Replacing Cast Iron Panel.................................................................................................................31
7.5 Replacement of Door Gasket ............................................................................................................31
7.6 Replacement of Glass.......................................................................................................................32
7.7 Door Latch Maintenance ...................................................................................................................33
7.8Paint..................................................................................................................................................33
8PARTS LIST..............................................................................................................................................34
9WARRANTY..............................................................................................................................................35

1
1 SAFETY
SUPREME FIREPLACES INC. congratulates you on purchasing an Astra 24 wood burning fireplace. This
manual describes the installation and operation of the Astra 24 non-catalytic wood heater. This heater meets the
2020 U.S. Environmental Protection Agency’s crib wood emission limits for wood heaters sold after May 15,
2015. Under specific test conditions this heater has been shown to deliver heat at rates ranging from 10,125 to
25,944 Btu/hr. In addition, this fireplace complies with the ULC-S610 and UL-127 standards.
SAFETY NOTICE: Carefully read this manual before installation and operation of this fireplace. A house
fire may result if not properly installed. To reduce the risk of a fire, follow the installation instructions.
Failure to follow instructions presented in this manual can lead to property damage, bodily injury or even
death. Alterations or modifications made on the unit or the installation is strictly forbidden as it may
predispose the user to hazardous risks. Contact your local building or fire officials for restrictions and
installation inspection requirements in your area and the need to obtain a permit.
WARNING: This unit is hot during operation; keep children, pets, flammable liquids, or combustible
materials at a safe distance. Ensure that all clearances to combustible materials are respected. Contact
with the unit during operation may cause severe harm. Install a safety screen to keep children and pets
away.
CAUTION:
•Do not connect this unit to a chimney flue serving another appliance.
•Do not connect to any air distribution duct or system.
•Never use chemicals to ignite the fire.
•Never burn waste or flammable fluids (such as gasoline, naphtha, or engine oil).
•Only burn dry natural cordwood.
•Never leave the unit unattended with the door open or unlatched.
•Only refuel this unit when the wood is reduced to embers.
•Always keep the door closed during operation.
•Do not operate this unit with a fireplace grate.
•Do not install an unvented gas log set into the firebox.
•Do not install this unit in a mobile home.
•Do not clean or service the unit while it is hot.
•Allow proper air flow by keeping the louvers/openings clear of any obtrusions.
Note: Failure to respect the above cautions may cause damages to the unit, damages to personal property,
bodily harm and will void the warranty. “This wood heater needs periodic inspection and repair for proper
operation. It is against federal regulations to operate this wood heater in a manner inconsistent with operating
instructions in this manual.”
This product can expose you to chemicals including carbon monoxide, which is known to
the State of California to cause cancer, birth defects or other reproductive harm. For more
information go to www.P65warnings.ca.gov/

2
2 GENERAL INFORMATION
2.1 Overall Dimensions
Figure 2-2: Astra 24 Clean Face Dimensions
Figure 2-1: Astra 24 Traditional Dimensions

3
2.2 Specifications
Appliance Type:
Adjustable Burn Rate Wood Heater –Non-Catalytic
Fuel Type:
Dry Cordwood
Maximum Log Length:
24 in (60.9 cm)
Burn Time1:
6 to 10 hrs
Firebox Volume:
2.4 ft3 (0.069 m3)
Heating Area:
500 to 2,000 ft2(45 to 185 m2)
Average Particulate Emissions Rate2:
1.91 g/hr
Average CO Emissions Rate3:
1.71 g/min
EPA Protocol:
Method 28R, ASTM2780-10, and ASTM2515-11
Efficiency (Crib Wood):
HHV4: 67.9% | LHV5: ***
Heat Output (Crib Wood):
12,237 to 23,872 BTU/hr (3,586 to 6,996 W)
Optimum Efficiency:
75%
Optimum Heat Output:
75,000 BTU (21.9 kWh)
Efficiency Protocol:
CSA B415.1-10
1
Depending on combustion air control setting (see Section 5.3 for further details).
2
Officially tested and certified by an independent.
3
Note that rate is smaller for low to medium/low burn rates.
4
Higher Heating Value.
5
Lower Heating Value.
WARRANTY REGISTRATION
Please register your SUPREME product online at http://www.supremem.com/warranty.php to ensure full
warranty coverage. Proof of purchase is required for all warranty claims.

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2.3 Combustion Air Control
The Combustion Air Control is a patented mechanism (Patent No: US
7,325,541 B2) that regulates the air flow into the firebox based on the
temperature of the unit. It is located on the top of the firebox, at the front
center of the unit. The combustion air control of the Astra 24 has two
components: the Activator and the Burn Rate Selector (see Figure 2-3). The
left combustion control lever is the Activator. When starting a fire or adding
a new load of wood, the Activator must be pushed in to allow a primary
source of air to enter the firebox. The Activator will retract automatically with
heat. The right combustion control lever is the Burn Rate Selector. The Burn
Rate Selector can slide sideways to achieve different burn rates. When the
Burn Rate Selector is positioned to the left, a maximum burn rate is achieved
and when it is positioned to the right, a minimum burn rate is set.
WARNING: Never manipulate the Combustion Air Control with bare
hands as it gets hot when the Astra 24 is in operation. Use the Cold
Hand Key (see Section 2.4) to adjust the Combustion Air Control.
2.4 Cold Hand Key
The Cold Hand Key is anaccessory that comes standard withthe Astra 24 fireplace
(Figure 2-4). The Cold Hand Key is a tool used to manipulate the Combustion Air
Control Levers when they are hot.
2.5 Chimney Sweeping Cap
The chimney sweeping cap found at the baffle of the Astra 24 allows easy access
for chimney sweeping without having to remove any components of the firebox
(Figure 2-5).
WARNING: The chimney sweeping cap should be blocking
the access to the chimney at all times during combustion.
A chimney sweeping cap that is not blocking the baffle hole
during combustion is a safety hazard, will overheat the
fireplace and void the warranty.
2.6 Door
The Astra 24 wood burning fireplace comes with a Pyroceramic
glass panel door. Pyroceramic is the highest grade available for
fireplaces and stoves and can withstand temperatures up to
1300oF. To remove the door, open the door, lift it and pull it
towards the bottom until the rod exits from the hinge holes.
Figure 2-3: Combustion Air Control’s
Activator and Burn Rate Selector
Figure 2-4: Cold Hand Key
Figure 2-5: Chimney Sweeping Cap

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2.7 Certification Label
The certification label contains important information regarding
the installation and operation of the Astra 24fireplace. In addition,
the serial number of the unit is permanently embossed onto the
top right corner. See Figure 2-6 for the location of the certification
label.
2.8 Removable Ash Lip
The Ash Lip is a removable accessory that comes standard with
the Astra 24 fireplace (Figure 2-8). It is installed on the door
holder (under the two small angled tags below the door) and
prevents ashes from falling onto the front of the hearth. The Ash
Lip can be installed with the door open or closed. It is safe to
operate the unit without the Ash Lip.
NOTE: The door of the Astra 24 must remain closed at all
times during operation.
2.9 Baffle Secondary Burn Technology
An innovative baffle design comprises of carefully engineered perforations that allow the introduction of
secondary air to increase the efficiency and heat output while offering an uncompromising view of the fire (Figure
2-7).
2.10 Cast Iron Interior
The Astra’s stainless steel firebox is lined with cast iron panels for an extra layer of durability and strength.
Designed to provide long-lasting heat and thermal protection, these industry-first, decoratively stamped panels
also provide the added benefit of the timeless beauty of cast iron. Forged in fire, tempered with time, the Astra
offers a lifetime of warmth.
Figure 2-6: Location of Certification Label with
Product Serial Number
Figure 2-7: Baffle Secondary Burn Technology

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2.11 Blower Kit
An AC tangential blower (electrical rating: 115V, 60Hz, and 56W) with a
variable speed control comes with the Astra 24 wood burning fireplace to
maximize efficiency (kit number BLK130CFM). Refer to Section 3.9 for
installation instructions.
WARNING: Make certain that the fireplace in not in operation and the
blower is unplugged (breaker off) before accessing the electrical wiring
of the blower kit.
CAUTION: Only a blower provided by SUPREME FIREPLACES INC. can
be installed into the fireplace. Substituting the blower kit may result in
overheating, will void the warranty and can be hazardous.
2.12 Optional Hot Air Kit
The Optional Hot Air Kit (kit number SU250) allows heat to be drawn from
the unit by a thermostatically controlled blower (electrical rating: 115 V and
60 Hz) and dispersed to different areas of the house. This option is
recommended when the fireplace is installed in an area below the maximum
heating space. A total of three kits can be installed onto one unit with a
maximum distance of 25 feet each. Note that a 5 inch insulated duct (part
number UCAC5) is required for the installation (item ordered separately).
Refer to Section 4.1for installation instructions.
WARNING: Make certain that the fireplace in not in operation and that hot air blower is not powered
(breaker off) before accessing the electrical wiring of the hot air kit.
CAUTION: Only a hot air kit provided by SUPREME FIREPLACES INC. can be installed onto the fireplace.
Substituting the hot air kit may result in overheating, will void the warranty and can be hazardous.
2.13 Optional Fresh Air Kit
The Optional Fresh Air Kit (kit number UPEA4) allows for exterior air (outdoors) to be drawn into the fireplace
during operation of the unit. Note that a 4 inch insulated duct is required for the installation (item ordered
separately). Refer to Section 4.2for installation instructions. Contact your local building official regarding
mandatory fresh air kit installations within your area.
CAUTION: Only a fresh air kit provided by SUPREME FIREPLACES INC. can be installed onto the
fireplace. Substituting the fresh air kit may result in overheating and will void the warranty.
Figure 2-8: Removable Ash Lip

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3 INSTALLATION INSTRUCTIONS
Before installing the unit, consult an authority having jurisdiction (such as
your municipal building department, your fire department, your fire
prevention department...) for any local codes and whether a permit is
required. In the absence of local codes, refer to the CSA B365 Installation
Code for Solid Burning Appliances and Equipment (Canada) or the ANSI
NFPA 211 Standard for Chimneys, Fireplaces, Vents and Solid Fuel-
Burning Appliances (USA). CAUTION: Modifications/alterations to the
unit/installation without written authorization from SUPREME
FIREPLACES INC. are strictly forbidden and will void the warranty.
Refer to Section 1 for further safety information. Carefully read the
instructions below before installing your Astra 24.
3.1 Location
Determine the location of the Astra 24 by taking into consideration the
following criteria:
•The size of the room with respect to the heat output of the fireplace.
•The proximity of windows, doors, and traffic flow.
•The necessary amount of space in front of the unit for the hearth
extension and mantel.
•The clearances to combustible materials.
•The passage of the chimney.
If possible, select a location for the fireplace that will minimize
the number of offsets in the chimney course. Offsets will reduce
the draft, complicate the chimney sweeper’s work, and increase
installation costs. Do not install an offset directly onto the
unit/anchor plate. Technical drawings outlining the chimney
route should be prepared prior to the installation. NOTE: The
cutting of joists and rafters for floor, ceiling, and roof chimney
penetrations will affect the load bearing capacities of the
dwelling structure. To determine whether additional support is
required, consult your local building codes. Improper cutting of
chimney openings inthe attic and roof willaffect the bearing and
thermal insulating capacity, as well as the weather tightness of
the dwelling. Avoid incorrect workmanship by consulting a
professional engineer or a certified installer.
Through examination of the floor construction, ensure that the
fireplace and chimney system is resting on a surface capable of
withstanding its weight. Consult your building codes to see
whether additional structural supports are required (applicable
for rare and isolated cases).
Avoid having the chimney outlet near any obstructions (such as
trees and roof offsets) as the draft of the chimney may be
affected by wind turbulence. Ideally position the outlet of the
chimney at the highest area of the roof.
NOTE: It is strongly recommended to install a carbon
monoxide (CO) and smoke detector near the location of the
unit.
Figure 3-1: Straight Wall Installation
Figure 3-2: Corner Installation
Figure 3-4: Space Required for Fresh Air Kit Installations
Refer to Section 4.3
Figure 3-3: Space Required for Forced Hot Air System
Installations
Refer to Section 4.2

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3.2 Chimney Installation
The Astra 24 is approved with a 6” chimney that is listed under the UL 103 /
ULC S629 standards (refer to Table 3-1). WARNING: Mixing chimney
components from different brands is a safety hazard and will void the
warranty on the unit. When connecting the unit to an existing chimney,
thoroughly inspect the condition of the chimney and that the installation
conforms with the requirements of the chimney manufacturer and the building
codes. Note that to avoid any unnecessary risk, it is often recommended
to replace the chimney system. Always respect the clearances to
combustibles from the chimney manufacturers; a minimum of two inch
clearance is usually required for prefabricated chimneys.
3.2.1 General Rules and Guidelines
1. Carefully read the instructions from the chimney manufacturer prior to
installation (manuals can be obtained from the chimney manufacturer’s
website or from the vendor). Unless specified, follow the chimney
manufacturer’s instructions for proper installation.
2. For optimal performance of the unit, it is recommended to install the
chimney system in an interior setting. To prevent drafting issues and
creosote buildups, avoid exterior installations of the chimney system in
regions that experience extreme cold conditions.
3. The minimum and the maximum height of the chimney from the base of the
unit are 15’ and 35’ respectively.
4. A minimum length of 12 inches of straight chimney is required from the top
of the unit before having an offset.
5. Do not install an elbow/offset directly onto the unit.
6. Only chimneys approved under the UL 103 / ULC S629 standards can be
installed onto the unit (refer to Table 3-1).
7. A 6” anchor plate is required to connect the fireplace to the chimney system.
The anchor plate can be secured onto the unit with 4 self-tapping screws.
8. The chimney installed onto the unit cannot be connected to another
appliance.
9. Enclose any portion of the chimney that extends to accessible spaces.
10. The clearance of the chimney to any combustible material cannot be less
than 2”; the 2” clearance cannot be filled with insulation or any non-
combustible material.
11. At least one support is to be incorporated in any chimney installation.
12. A firestop is required in the joists/frames where the chimney goes through
(ceilings, floors, walls, and roof).
13. To prevent drafting issues, avoid deviations wherever possible.
14. The chimney shall extend at least 3’ above its point of contact with the roof
and at least 2’ higher than wall, roof, or adjacent building within a 10’ radius.
15. A secure brace is to be installed if the chimney extends a minimum of 5’
above the contact point with the roof.
16. A rain cap must be installed on top of the chimney to avoid internal damage
and/or corrosion.
17. Consult the chimney manufacturer for clearances to combustibles when
installing a combustible chimney enclosure above the roof.
Figure 3-5: Straight Interior Installation
Figure 3-6: Exterior Installation

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3.2.2 Listed UL 103 / ULC S629 Approved Chimney Models (Reference Table)
Note that only chimney models listed in Table 3-1 can be installed for the Astra 24.
Table 3-1: List of Approved Chimney Models
Manufacturer
Models
American Metal
•HS, AC Triple Wall, 6” inner diameter
•HSS, AC Triple Wall, 6” inner diameter
FMI (US only)
•AC, AC Triple Wall, 6” inner diameter
ICC
•Excel 2100, 1” Solid Pack, 6” inner diameter
Metal Fab
•Temp Guard, 1” Solid Pack, 6” inner diameter
Olympia Chimney
•Ventis, 1” Solid Pack, 6” inner diameter
Security Chimney
•ASHT+, 1” Solid Pack, 6” inner diameter
•S-2100+, 2” Solid Pack, 6” inner diameter
Selkirk
•Super Pro (SPR), 1” Solid Pack, 6” inner diameter
•Super Pro 2100 (ALT), 2” Solid Pack, 6” inner diameter
•Hart & Cooley (TLC), 1” Solid Pack, 6” inner diameter
•Sure-Temp (ST), 1” Solid Pack, 6” inner diameter
•Super Vent (JSC), 1” Solid Pack, 6” inner diameter
•Super Vent 2100 (JM), 2” Solid Pack, 6” inner diameter
•Ultra-Temp (UT), 1” Solid Pack, 6” inner diameter
•UltimateOne, 1” Solid Pack, 6” inner diameter
•CF Sentinel (CF), 2” Solid Pack, 6” inner diameter
Simpson Dura-Vent
•Dura Tech, 1” Solid Pack, 6” inner diameter
•Dura Plus HTC, 2” Solid Pack, 6” inner diameter
•Dura Plus, AC Triple Wall, 6” inner diameter
3.2.3 Chimney Installation Instructions
1. Cut and frame square openings in the floors, ceilings, and roof where the chimney will pass through while
taking into consideration the minimum clearance to combustibles.
2. In the ceiling/floor openings, install a chimney manufacturer’s firestop from below. Install the chimney
manufacturer’s attic radiation shield from above in the chimney opening to the attic. Ensure to install the
appropriate firestop for ceilings and walls.
3. Install the chimney manufacture’s anchor plate onto the unit.
4. Install the chimney lengths according the manufacturer’s instructions and ensure proper fastening/locking of
the joints.
5. Install the roof support once the desired height has been reached.
6. Position the roof flashing. Note that for sloping roofs, position the upper portion of the flashing under the
shingles and position the lower portion of the flashing above the shingles. Seal the joint between the roof
and the flashing with roofing cement or silicone. Secure the flashing to the roof with roofing nails.
7. Install the storm collar over the flashing by tightening the supplied bolt or through the flange mechanism
(depends on chimney brand). Seal the joint between the storm collar and the chimney using a silicone
caulking. WARNING: Do not seal, caulk, or obstruct the ventilation openings when installing a
ventilated flashing.
8. Install the chimney rain cap.
Refer to Figure 3-5 and Figure 3-6 for typical chimney installations.

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3.2.4 Offset Installation
An offset installation (Figure 3-7) consists of the use of elbows to deviate from
unavoidable obstacles or to extend the chimney outside. The following list is a few
general rules to take note when installing offsets:
•A maximum of 2 offsets (2 elbows per offset) is permitted per installation.
•The maximum deviation is 45oin Canada and 30oin the US.
•Secure the elbows and the chimney components according the instructions
from the chimney manufacturer.
•A support strap, a wall support, or a roof support must be installed above each
offset to allow adequate support to the vertical chimney lengths.
•Never install an elbow in an opening of a floor, wall, ceiling, or roof. In
addition, only vertical chimney sections can be installed within ceiling/floor
openings.
•A minimum length of 12 inches of straight chimney is required from the top of
the unit before having an offset.
•Install a support for the first 15’ of chimney.
The following are instructions for offset installations:
1. Rotate the elbow in the required direction and secure it to the adjacent
chimney section according to the chimney manufacturer’s instructions.
2. Follow the chimney manufacturer’s instructions to install the chimneylength(s)
necessary for the offset.
3. Once the desired offset length has been achieved, install the second elbow to
redirect the venting to the vertical position.
4. Cut an opening in the floor/ceiling to allow the chimney to pass through.
5. Install the appropriate firestop.
CAUTION: For offset installations, always install a ventilated flashing and a
roof firestop unless otherwise specified by the chimney manufacturer.
Never install an elbow directly onto the unit.
3.2.5 Angled Wall Radiation Shield
For chimney installations requiring to pass through a combustible wall at a 30o(Canada) or 45o(Canada and
US) angle, an angled firestop or an angled wall radiation shield from the chimney manufacturermust be installed
within the wall opening. Install the angled firestop and angled wall radiation shield according to the
manufacturer’s instructions. It is recommended to use an insulated angled wall radiation shield in areas that
experience cold climates.
3.2.6 Connecting to a Masonry Chimney
The Astra 24fireplace can be connected to a masonry chimney that complies with current
national and municipal building codes. A 6 inch chimney liner that complies with ULC
S635 M2000 (Canada) or UL 1777 (US) standards must be installed within the existing
masonry chimney. Note that the 6CON connector (manufactured by SUPREME
FIREPLACES INC.) must be installed to connect the prefabricated chimney to the liner
(6CON sold separately). Refer to Figure 3-8.
Note that priorto installation, an inspection from anauthority having jurisdiction is required
to determine whether the masonry chimney:
•Is constructed in accordance with national and municipal building codes.
•Is in good condition. Note that repairs must be performed on any cracked or
missing bricks.
Figure 3-7: Offset Installation
Figure 3-8: 6CON Liner
Connector

11
•Is thoroughly cleaned of any soot or creosote.
•Is not connected to another appliance such as a furnace, hot water heater, or another fireplace.
•Has a flue of adequate size for proper installation of the venting.
•Respects minimum clearances to combustibles.
It is recommended to position the fireplace asclose aspossibleto themasonry chimney to ensure proper venting.
The prefabricated chimney must penetrate at least 3 inches within the masonry chimney before connecting the
liner. Elbows can be used within the masonry chimney, with a maximum deviation of 30oin US and 45oin the
Canada. Note: A minimum length of 12 inches of straight chimney is required from the top of the unit
before having an offset.
The installation of the prefabricated chimney and the liner must comply with the manufacturer’s instructions. The
following are instructions in installing the venting of the Astra 24 running through a masonry chimney:
1. Install the anchor plate onto the unit.
2. Position the fireplace to the recommended location.
3. Install the initial prefabricated chimney lengths and elbows.
4. Mark the area where the prefabricated chimney will penetrate the masonry chimney.
5. Remove the fireplace to allow for sufficient space to work.
6. Make a hole tothe requiredsize to allow for the prefabricated chimney tobe insertedfreely in themasonry
chimney. Note that the appropriate firestops need to be installed if running the prefabricated chimney
through a combustible wall.
7. Install the remaining prefabricated chimney components center with the masonry chimney.
8. Align the flange holder of the 6CON connector with the studs facing upwards to the center of the
prefabricated chimney section (elbow or tee) and secure it with three self-tapping screws.
9. Reposition the fireplace to its initial position.
10. Overlap by 1” the lower end of the liner in the expanded portion of the 6CON connector and secure the
joint with 3 #8 stainless steel self-tapping screws.
11. From the roof, slide the liner down the masonry chimney until itreaches theupper end ofthe prefabricated
chimney.
12. Install the upper portion of the 6CON liner connector to the flange holder by aligning the threaded studs
to the holes and complete the connection by tightening the wing nuts.
13. Seal any openings around the prefabricated chimney and the 6CON connector with refractory cement
resistant to high temperatures.
Figure 3-9: (A) Connection into a masonry chimney through an elbow/liner; (B) connection into a masonry chimney through a
tee/liner; (C) detailed drawing of masonry chimney connection.

12
3.3 Surround Installation
The Astra 24 can be installed with either the Traditional surround or the Clean Face surround.
3.3.1 Traditional Surround
The traditional surround comprises louvers below (intake) and above (outtake) the door. All components and
fasteners are included in the surround kit. Refer to Figure 3-12 Table 3-2 for the instructions below.
1. Remove the door of the unit and place it on a soft surface, such as a carpet or cardboard, to avoid any
scratches or damages.
2. Align the bottom front support bracket (Item 2) to the intake opening and fasten it in place (Figure 3-11).
3. Align the top front support bracket (Item 2) to the outtake opening and fasten it in place (Figure 3-11).
4. Place the surround (Item 3 in Figure 3-12) within the door holder and secure it in place with four black
screws (one on each corner). Make sure that the handles of the Combustion Air Control pass through
the slots of the surround.
5. Reinstall the door onto the unit.
6. Secure the Intake Swivel Covers on the bottom sides of the unit to the closed position (Figure 3-10).
WARNING: For traditional surround installations only.
Figure 3-10: Intake Swivel Cover Closed
WARNING: For Traditional Surround Installations Only
Figure 3-11: Top and Bottom Front Support Bracket
Installation for Traditional Surround

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3.3.2 Clean Face Surround
The Clean Face surround comprises no louvers; however, an intake into the chase and an outtake through
gravity ducts is required for this configuration. The instructions below describe the installation of the Clean Face
surround. Refer to Figure 3-15 Table 3-3 for the instructions below. Refer to Section 3.4 for Gravity Kit installation
instructions.
1. Remove the door of the unit and place it on a soft surface, such as a carpet or cardboard, to avoid any
scratches or damages.
2. Align the bottom Clean Face front cover (Item 1) and fasten it in place (Figure 3-14).
3. Align the top Clean Face front cover (Item 1) and fasten it in place (Figure 3-14).
4. Place the surround (Item 4 in Figure 3-15) within the door holder and secure it in place with 4 black
screws (one on each corner). Make sure that the handles of the Combustion Air Control pass through
the slots of the surround.
5. Reinstall the door onto the unit.
6. Secure the Intake Swivel Covers on the bottom sides of the unit to the open position (Figure 3-13).
Table 3-2: 24ATFA-11 Components
TRADITIONAL SURROUND
ITEM
DESCRIPTION
QTY
2
Front support bracket
2
3
Traditional surround
1
Figure 3-12: Traditional Surround Components

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Table 3-3: 24ATFA-12 Components
CLEAN FACE SURROUND
ITEM
DESCRIPTION
QTY
1
Clean Face front cover
2
4
Clean Face surround
1
7
Flange adapter
2
Figure 3-13: Intake Swivel Cover Kept Open for Clean Face
Installations
Figure 3-15: Clean Face Surround Components
Figure 3-14: Top and Bottom Front Cover Installation for
Clean Face Surround
Figure 3-16: 8 Inch Knockouts for Gravity Kit
Figure 3-17: Tabs Inside the 8 Inch Knockouts
Figure 3-18: Tabs Inside the 8 Inch Knockouts

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3.4 Gravity Kit Installation
The Clean Face surround comprises no louvers; however,
an intake into the chase and an outtake through gravity
ducts is required for this configuration. The instructions
below describe the installation of the intake openings, and
the gravity ducts/outtakes. Note that in order to connect
the gravity ducts to the sides of the chase, the sides of the
chase need to be constructed and the front of the chase
needs to remain open; to connect the gravity ducts to the
front of the chase, the sides need to remain open and the
front of the chase needs to be constructed (Figure 3-20).
Please note thatthe SUPREME KG540 kit and the UCAC8
semi-rigid insulated ducts are required for the Gravity Kit
installation (Figure 3-19).
1. Remove the two 8” knockouts (2) at the top of the
unit using a flat head screwdriver (Figure 3-16).
2. Using the knockout as a template, cut the exposed
insulation. Make sure to remove any pieces of
insulation that has fallen into the unit.
3. Bend the tabs inside the 8 inch knockouts (Figure
3-17) upwards.
4. Install the 8 inch duct adapters (Item 7 in Figure 3-
15) through the newly cut knockouts and screw
them to the bent tabs (Figure 3-18).
5. Determine the two locations of the air intakes on
the chase and cut a rectangular opening 10.5” (W)
X 9.5” (H). Note that a distance of 3 inches is
required from the floor.
6. Determine the two locations of the air outtakes on
the chase and cut a rectangular opening 10.5” (W)
X 9.5” (H). Note that a minimum distance of 64
inches is required from the floor and a minimum of
6 inches is required from the ceiling (Figure 3-25).
Please note that the air outtake grilles can be
installed in the same room or in different rooms
from each other. If the grilles are installed at
different heights, more heat will be distributed to
the highest one.
7. From the exterior of the chase, place the duct/louver adapter into the air outtake hole and secure it onto
the wall with screws. Repeat for the other outtake.
8. Within the chase, place the grooved end of the adjustable 45oelbow into the flange of the duct/louver
adapter and secure it using aluminum tape. Repeat for the other outtake.
9. Measure the distance between the flange adapter on top of the unit and the flange of the duct/louver
adapter and cut the 8 inch semi-rigid insulated duct (SUPREME part number UCAC8) to the necessary
length. Repeat for the other outtake.
10. Complete the connections by sliding the ducts over the flange adapters and the flanges of the duct/louver
adapters and tighten both ends with the worm gear clamps.
11. From the exterior of the chase, fasten the grilles over the intake and outtake openings with the beige
screws.
Table 3-4: KG540 Components
ITEM
DESCRIPTION
QTY
ILLUSTRATION
LW1021
11”x 12” grille
for intakes and
outtakes
4
LW1000
Duct/louver
adapter
2
4358C26
45° elbow, 8”
diameter
2
HAMGC-128
8” worm gear
clamp
4
Figure 3-19: KG540 Assembly Diagram

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WARNINGS:
•The gravity ducts must extend upwards from the top of the unit and cannot exceed 10 feet.
•The ducts should never extend downwards; only horizontally or upwards.
•The air outtakes must be installed at a minimum of 64 inches from the floor.
•The gravity ducts must not be connected to a central heating system.
•A clearance must be maintained between the gravity ducts and the chimney.
•The intake swivel covers at the bottom sides must remain open for all Clean Face installations. Refer to
Figure 3-13.
•Refer to Figure 3-25 for clearances to combustibles.
Figure 3-20: Gravity Kit Installation

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3.5 Framing
The Astra 24 can be placed directly onto or against
normal, combustible construction materials such as
lumber, plywood, millboard, particleboard, drywall and
decorative wood paneling. The fireplace should NOT be
placed directly against or be in contact with an insulation
material. A portion of the framing on the face of the chase
must be constructed with nominal 2" x 3" or 2” X 4” metal
studs and the remainder can be constructed with nominal
2” X 3” or 2” X 4” lumber. Refer to Figure 3-21 for framing
design. The framing must be nailed or screwed onto the
floor and to the ceiling.
CAUTION: Respect the framing design outlined in
Figure 3-21 as well as the chimney manufacturer’s
clearances to combustibles.
WARNING: Do not nail or screw framing components
onto the fireplace.
3.6 Hearth Extension
The hearth extension of the Astra 24 must comprise of a
non-combustible material, such as steel, cement or
mortar, bricks, or ceramic tiles. Note that unidentified
materials may be combustible; verify product
specifications prior to installation. In addition, the non-
combustible hearth extension must be constructed of
materials having a minimum R-Value of 0.390 (Refer to
Section 3.6.1). The hearth extension must extend a
minimum of 18 inches from the front of the door, 8 inches
from side of the outer frame of the door, and extended all
the way to the unit (see Figures 3-22 and 3-23 for
dimensions).
CAUTION: Make sure to remove any carpet or fabric
under the hearth extension.
Note: If the fireplace is raised a minimum of 4 inches from
the non-combsutible hearth extension, there is no
minimum required R-Value to respect.
Figure 3-21: Minimum Astra 24 Framing Dimensions
Figure 3-22: Hearth Extension