HearthStone Stowe DV 8321 Troubleshooting guide

Stowe Model 8321
Manual: 6400-404220
Revision: 6 - 2/10/2011
Stowe DV
(Model 8321)
GAS-FIRED DIRECT-VENT HEATER
Owner’s Manual & Installation Guide
READ THIS OWNER’S MANUAL
Operate and Maintain This Gas Heater
According To This Instruction Manual.
Save These Instructions!
WARNING: IF THE INFORMATION IN THESE
INSTRUCTIONS IS NOT FOLLOWED EXACTLY, A
FIRE OR EXPLOSION CAN RESULT CAUSING
PROPERTY DAMAGE, PERSONAL INJURY OR
LOSS OF LIFE.
Do not store or use gasoline or other flammable vapors and
liquids near this or any other gas appliance.
WHAT TO DO IF YOU SMELL GAS:
Do not try to light any appliance.
Do not touch electrical switches; do not use the
phone in your building.
Immediately call your gas supplier from a
neighbor’s phone. Follow your gas supplier’s
instructions.
If you cannot reach your gas supplier, call the fire
department.
A qualified installer, service agency or gas supplier must
perform installation and service. The Commonwealth of
Massachusetts requires that a licensed gas fitter or licensed
plumber install all gas lines and gas fittings.
AVERTISSEMENT: ASSUREZ-VOUS DE BIEN
SUIVRE LES INSTRUCTIONS DONNÉ DANS CETTE
NOTICE POUR RÉDUIRE AU MINIMUM LE RISQUE
D’INCENDIE OU POUR ÉVITER TOUT DOMMAGE
MATÉERIEL, TOUTE BLESSURE OU LA MORT.
Ne pas entresposer ni utiliser d’essence ni d’autre vaperurs
ou liquides inflammables dans le voisinage de cet apprareil
ou de tout autre appareil.
QUE FAIRE SI VOUS SENTEZ UNE ODEUR
DE GAZ:
Ne pas tenter d’allumer d’appareil.
Ne touchez à aucun interrupteur. Ne pas vous
servir des téléphones se trouvant dans le batiment où
vous vous trouvez.
Appelez immédiatement votre fournisseur de gaz
depuis un voisin. Suivez les instructions du
fournisseur.
Si vous ne pouvez rejoindre le fournisseur de gaz,
appelez le service des incendies.
L’installation et service doit être exécuté par un installateur
qualifié, agence de service ou le fournisseur de gaz.

Intentionally Blank

Information Sheet
Use this page to record all relevant information concerning the purchase, installation, and maintenance of your
Stowe Model 8321 Direct -Vent heater. This information will facilitate servicing, purchase of replacement parts,
and warranty claims (if necessary). Keep your original receipt in a safe place as proof of purchase.
Serial Number:
Fuel type: Natural Gas Liquid Propane
Sold by: Date of Purchase:
Address:
Phone:
E-mail Website:
Installed by: Date of Installation:
Address:
Phone:
E-mail Website:
Gas Supplier:
Address:
Phone:
E-mail Website:
Read this Owner’s Manual before installing or operating your Stowe. Retain this manual for future reference.
SERVICE RECORD
Date Who Performed Work Work Performed Notes:
WHAT WHEN
Firebox Cleaning............. annually
Glass Cleaning................ as needed
Gaskets.................... Replacement as needed

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
Table of Contents
Introduction............................................................................................................................................................3
Safety & Good Practices.......................................................................................................................................4
Specifications........................................................................................................................................................6
Owner’s Information .............................................................................................................................................7
DAILY OPERATION ................................................................................................................................................................7
EFFICIENCY..........................................................................................................................................................................7
CONDENSATION....................................................................................................................................................................7
Installer’s Information...........................................................................................................................................8
CODES ................................................................................................................................................................................8
ITEMS REQUIRED FOR INSTALLATION.......................................................................................................................................8
PACKING LIST.......................................................................................................................................................................8
UNPACKING AND INSPECTION.................................................................................................................................................8
FIREBOX ACCESS .................................................................................................................................................................9
HEARTH &FLOOR PROTECTION .............................................................................................................................................9
CLEARANCE TO COMBUSTIBLES .............................................................................................................................................9
ACCEPTABLE DIRECT-VENT TERMINATION CAP LOCATIONS ....................................................................................................11
Venting Information ............................................................................................................................................12
VENTING CONNECTION........................................................................................................................................................12
VENTING COMPONENTS &CONFIGURATION...........................................................................................................................13
STANDARD HORIZONTAL TERMINATION MINIMUM VENTING KIT................................................................................................20
Electrical Connections........................................................................................................................................21
WIRING INSTRUCTIONS........................................................................................................................................................21
WIRING DIAGRAM................................................................................................................................................................22
Gas Supply & Connections................................................................................................................................23
GAS CONNECTIONS ............................................................................................................................................................23
GAS SUPPLY......................................................................................................................................................................23
GAS PRESSURE ADJUSTMENT..............................................................................................................................................24
Log Placement.....................................................................................................................................................25
INSTALLING THE LOG SET ....................................................................................................................................................25
REMOVAL OF LOG SET........................................................................................................................................................26
Initial Operation Preparation..............................................................................................................................27
Lighting Instructions & Initial Adjustments......................................................................................................28
LIGHTING INSTRUCTIONS .....................................................................................................................................................28
AIR SHUTTER ADJUSTMENTS ...............................................................................................................................................29
PILOT ADJUSTMENT ............................................................................................................................................................29
Routine Maintenance & Care..............................................................................................................................31
CLEANING THE UNIT ...........................................................................................................................................................31
GLASS CLEANING ...............................................................................................................................................................32
Parts List..............................................................................................................................................................33
Troubleshooting..................................................................................................................................................34
Rating Label.........................................................................................................................................................37
Limited Warranties..............................................................................................................................................38
2

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
3
INTRODUCTION
Congratulations on your purchase of a Stowe Gas-
Fired Direct-Vent heater. The Stowe, by
Hearthstone, incorporates the latest in balanced
vent gas technology, which will provide you with
clean, efficient heat for years to come. The cast iron
gives the Stowe a pleasing look that is maintained
with minimum care.
The Stowe will provide you with years of practical
and convenient service. However, as with any gas
appliance, the unit must be properly installed and
maintained by qualified service personnel to ensure
safe and trouble-free operation.
Your Stowe is equipped with a standing pilot which:
1. Generates a milli-volt signal that powers
(opens) the millivolt gas valve.
2. Lights the main burner when the thermostat
calls for heat.
This unit is equipped with an On/Off/T’stat switch
and a variable output control. The variable output
control is located on the gas control valve. It allows
you to vary the heat output, along with the flame
height to suit personal taste. Heat output can be
reduced {set to “LOW”} during the Fall and Spring,
when the need for heat is reduced and increased
{set to “HIGH” during Winter months, when the need
for heat is the greatest.
A wall-mounted thermostat is provided by
Hearthstone. Regardless of how you set the variable
output control, when the optional thermostat has
been installed and the On/Off/T’stat switch is set to
“T’stat”, the wall-mounted thermostat will control the
on/off cycling of the unit. At any time, you can
override the thermostat with the On/Off/T’stat switch
by setting it to “ON” or “OFF”.
The Unit can also be equipped with an optional
blower-fan kit, which operates independently of the
thermostat. The fan switch allows you to turn the fan
on or off and control the speed of the fan to suit your
needs. The fan will automatically turn on when the
stove is hot and cycle off when the unit is no longer
hot.
Also available are two different optional remote
controls. Both of the remote controls are capable of
turning the unit on and off. One of the optional
remotes also allows you to control the temperature
of the room from anywhere in the vicinity of the unit.
If “ON” & “OFF” are the only controls required; Kit #
90-56912 can be used. If you would like to control
the temperature via the remote control, use Kit # 90-
56914.
READ THIS OWNER’S MANUAL
Operate, and maintain, this gas heater according to
the instructions in this manual. For your safety, and
years of trouble free operation, read this manual in
its entirety.
THIS HEATER MUST BE INSTALLED AND
MAINTAINED BY QUALIFIED SERVICE
PERSONNEL
Verify the gas connections and venting systems with
requirements of local, regional or national installation
codes. Qualified service personnel must inspect the
gas heater before use, and at least annually.

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
SAFETY &GOOD PRACTICES
Your Stowe is an extremely efficient, durable
appliance utilizing today’s best technologies. By
following a few simple safety precautions and by
performing minimal maintenance, the unit will remain
appealing while providing years of quality
performance.
The installation must conform to local codes or, in
the absences of local codes, the current National
Fuel Gas Code, ANSI Z223.1 (NFPA 54) or
CAN/CGA B149 Installation Code. (Installer
l’appareil selon les codes ou réglements locaux, ou,
en l’absence de tells réglements, selon les Codes
d’installation CAN/CGA B149.)
Do not use this appliance if any gas control part was
under water. Immediately call a qualified service
technician to inspect the heater and to replace any
part of the control system and gas control that was
submerged. (Ne pas se servir de cet appareil s’il a
été plongé dans l’eau, complétement ou en partie.
Appeler un technicien qualifié pour inspector
l’appareil et remplacer toute partie du systéme de
contrôle et toute commande qui ont été plunges
dans l’lau.)
During the first few hours of operation, the appliance
may produce a slight smoke and/or odor. This is
normal during the first several burns. During the
initial burn, open a window(s) to assist in the
removal of the smoke/odor. If the logs appear to
smoke, turn the heater off and call a qualified
service technician.
You must disconnect the appliance and its individual
shutoff valve from the gas supply piping system
during any pressure testing of that supply system at
test pressures in excess of ½ psig. (3.5k Pa).
FIRE HAZARD
Do not store or use gasoline or other flammable
vapors or liquids in the vicinity of this appliance. The
Stowe should be located out of traffic and away from
furniture, draperies, clothing, and flammable
material.
SHOCK HAZARD
When equipped with an optional blower.
This appliance is equipped with a three-prong
(grounding) plug for protection against shock
hazard, and must be plugged directly into a properly
grounded three-prong receptacle. Do not cut, or
remove, the grounding prong from the plug.
VENT TO THE OUTSIDE
Never vent the gas heater to other rooms, or
buildings – always vent outside. This gas appliance
must not be connected to a chimney flue serving a
separate solid-fuel burning appliance.
SERVICE CAUTION
If you believe your Stowe is not performing properly,
in any way, immediately discontinue operation until
the unit is inspected, and approved for use by
qualified service personnel. Prior to servicing the
unit, turn the valve control knob clockwise to “OFF”.
The unit should be cool prior to servicing and
cleaning. Any safety screen, guard, or component
removed during servicing must be replaced before
operation. Use of any components not supplied by
Hearthstone voids all warranties. Do not substitute
components.
HOT SURFACES
Certain exposed surfaces of the Stowe will reach
high temperatures during normal operation.
Clearances to combustibles must be maintained, as
specified in the “Clearances To Combustibles”
section of this manual.
Due to high temperatures, the appliance must be
located out of traffic and away from furniture,
draperies, clothing, and flammable materials.
Alert children, and adults, to the hazards of high
surface temperatures, and to stay away to avoid
burns to skin or possible clothing ignition.
Carefully supervise young children when in the
same room as the appliance. Do not place
clothing, or other flammable material, on or near,
the appliance. (Surveille les enfants. Garder les
vêtements, les meubles, l’essence ou autres
liquides à vapeur inflammables lin de l’appareil.)
Clean the area around, under, and behind the unit
on a regular basis to prevent the accumulation of
dust and lint.
NEVER BURN PAPER,WOOD OR OTHER
MATERIALS
This gas heater is designed to burn natural gas, or
liquid propane (LP). Never burn any fuel not
intended for use with this unit.
WARNING! THIS GAS APPLIANCE MUST NOT BE
CONNECTED TO A CHIMNEY FLUE SERVING A
SEPARATE SOLID-FUEL BURNING APPLIANCE
WARNING! DO NOT OPERATE THE APPLIANCE
4

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
WITH THE FRONT GLASS REMOVED, CRACKED,
OR BROKEN.
WARNING! REPLACEMENT OF GLASS MUST BE
DONE BY A LICENSED OR QUALIFIED SERVICE
PERSON.
WARNING! ONLY OPEN FRONT DOOR FOR
ROUTINE SERVICE. DO NOT SLAM THE DOOR
OR STRIKE THE GLASS.
CERAMIC LOG SAFETY
If the decorative ceramic log materials supplied with
the Stowe are damaged, or missing, they must be
replaced with the same, approved replacement parts
supplied by Hearthstone. These components affect
the combustion quality, and safety of the heater. Do
not replace ceramic logs with unapproved ceramic
logs, or any other material.
Always wear gloves and safety goggles while
handling the log set and ember materials.
ELECTRICAL HAZARD!
When the optional blower kit is installed, the Stowe
must be electrically grounded in accordance with
local codes, or in the absence of local codes, with
the National Electrical Code, ANSI.NFPA 70 in the
U.S. or CSA C22.1 Canadian Electrical Code in
Canada. The three-prong grounded plug must be
plugged directly into a properly grounded three-
prong receptacle. Do not cut, or remove the
grounding prong from the plug or otherwise attempt
to circumvent the grounding protection provided with
the unit.
DO NOT LIGHT PILOT OR PAN BURNER BY
HAND
The standing pilot light on this gas heater is lit by
using a piezoelectric spark generator as described
elsewhere in this manual. Never attempt to light the
pilot, or main burner, by hand with a match or lighter.
If, after repeated attempts, the pilot light fails to light,
discontinue operation; turn off the gas at the gas
control valve, and immediately contact qualified
service personnel for assistance.
Certified for use by:
Board of State Examiners of Plumbers and
Gasfitters
100 Cambridge Street, Room 1511
Boston, Massachusetts 02202
MOBILE HOME INSTALLATIONS
This appliance may be installed in an aftermarket,
permanently located, manufactured mobile home,
where not prohibited by local codes.
This appliance is only for use with the type(s) of gas
indicated on the rating plate. This appliance is not
convertible for use with other gases, unless a
certified kit is used.
(Cet appareil peut être installé dans un maison
préfabriquée (mobile) déjá installée á demeure si les
réglements locaux le permettent.
Cet appareil doit être atilisé uniquement avec les
types de gas indiqués sur la plaque signalétique. Ne
pas l’utiliser avec d’autres gas sauf si un kited
conversion certifié est installé. )
SERVICE CAUTION
Replace any shield, door, or safety screen
component removed for servicing prior to operating
the stove. If you believe your Stowe is not
performing properly in any way what so ever;
immediately discontinue operation until qualified
service personnel have inspected the unit. Always
shut off the gas, and electricity (if equipped), to the
stove while servicing. Make sure the unit is not hot
when servicing, or cleaning. Use of any components
not supplied, or specified by Hearthstone on the
stove or vent system voids all warranties. Do not
substitute components.
5

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
SPECIFICATIONS
LISTED:Gas-Fired Direct-Vent Fireplace Heater
Model: Stowe Direct-Vent Gas Fireplace Heater (8321)
Testing Agency: Intertek Testing Services NA, Inc. (ITS)
Tested to: ANSI Z21.88-2002, CSA 2.33-M02, CAN/CGA2.17-M91
Certified for Canada, CSA P.4.1
Approved for Mobile Home Installation (see page 5)
Figure 1: Stowe 8321 Dimensions
SPECIFICATION: NG LP
INPUT RATING (Btu/hr) 0-2000 ft 26,000 26,000
INPUT RATING (Btu/hr) 2000-4500 ft 25,500 25,500
ORIFICE SIZE (DMS) 0-2000 ft 40 53
ORIFICE SIZE (DMS) 2000-4500 ft 41 54
MANIFOLD PRESSURE - LO SETTING (in. W.c./kpa) 1.2/0.3 3.3/0.8
MANIFOLD PRESSURE - HI SETTING (in. W.c./kpa) 3.5/0.87 10.0/2.48
INLET PRESSURE - LO (in.w.c./kpa) 5.0/1.24 11.0/2.88
INLET PRESSURE - HI (in.w.c./kpa) 7.0/1.74 13.0/3.22
MINIMUM INPUT RATING (btu/hr) 15,600 15,600
MAXIMUM OUTPUT (btu/hr) 0-2000 ft 18,100 18,100
6

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
OWNER’S INFORMATION
The installation must conform with local codes or, in
the absences of local codes, the current National
Fuel Gas Code, ANSI Z223.1 (NFPA 54) or
CAN/CGA B149 Installation Code. (Installer
l’appareil selon les codes ou règlements locaux, ou,
en l’absence de tels règlements, selon les Codes
d’installation CAN/CGA-B149.)
Do not use this appliance if any gas control
part was under water. Immediately call a
qualified service technician to inspect the
heater, and to replace any part of the control
system and gas control that was submerged.
(Ne pas se servir de cet appareil s’il a été
plongé dans l’eau, complètement ou en partie.
Appeler un technicien qualifié pour inspector
l’appareil et remplacer toute partie du système
de contrôle et toute commande qui ont été
plongés dans l’lau.)
DAILY OPERATION
The Stowe gas-fired heater is operated easily by the
homeowner once it is installed and adjusted by
qualified service personnel. The unit is controlled via
the wall-mounted thermostat during the heating
season. Set the thermostat to the desired room
temperature and the unit will cycle on and off as
required. By adjusting the variable output control
located on the gas control valve, the rate of heat
output can be varied to meet the heating
requirements of the season. Choosing a low flame
setting will result in longer burn cycles at a reduced
output, while choosing a high flame setting will result
in a shorter, hotter burn cycle. Through trial and
error, the homeowner can select the optimum flame
size for their setting, and application.
EFFICIENCY
During the summer non-heating season, switch the
wall thermostat to “OFF”, and turn off the pilot by
turning the gas control to “OFF”. This will improve
the overall efficiency of the unit as the heat from the
pilot is wasted. When putting the unit back into
service, follow the lighting instructions described on
page 28.
CONDENSATION
When burned, fuel gasses produce Carbon Dioxide
+ Carbon Monoxide + Carbon + Water. So, when the
unit is first lit, especially when cool, it is normal to
experience some water condensation on the inside
of the window glass. This condensation will
evaporate within the first few minutes of operation. If
continuous condensation is observed on the window
glass, or dripping water is seen coming from any
part of the unit or venting system (chimney),
immediately discontinue operation of the unit, and
contact qualified service personnel.
7

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
INSTALLER’S INFORMATION
CODES
Adhere to all local codes or, in their absence, the
latest edition of THE NATIONAL FUEL GAS CODE
ANSI Z223.1 (NFPA 54) or CAN/CGA B149
Installation Code that can be obtained from:
AMERICAN NATIONAL STANDARDS INSTITUTE, INC.
1430 BROADWAY
NEW YORK, NY 10018
www.ansi.org
OR
NATIONAL FIRE PROTECTION ASSOCIATION, INC.
BATTERY MARCH PARK
QUINCY, MA 02269
www.nfpa.org
The appliance when operated with a blower installed
must be electrically connected and grounded in
accordance with local codes or, in the absence of
local codes, with the current NFPA 70-National
Electrical Code or CSA C22.1-Canadian Electric
Code.
A manufactured home (mobile) OEM installation
must conform to the Manufactured Home
Construction and Safety Standard, Title 24 CFR,
Part 3280 (U.S.) or Standard for Manufactured
Home Installation, ANSI/NCBCS A225.1 or Standard
for Gas Equipped Recreational Vehicles and mobile
Housing, CSA Z240.4.CAN/SCA Z240 MH
(Canada). (Installer l’appareil selon les codes ou
règlements locaux, ou, en l’absence de tels
règlements, selon les Codes d’installation
CAN/CGA-B149.)
For installations from 610-1370 meters (2000-4500
ft.) the orifice sizes (DMS) for natural and propane
gas are 41 and 54 respectively. See data plate for
additional information. For high altitude installations
consult the local gas distributor or the authority
having jurisdiction for proper rating methods. If the
installer must convert the unit to adjust for varying
altitudes, the information sticker must be filled out by
the installer, and adhered to the appliance at the
same time of conversion. (Cet appareil est equipè
pour des altitudes compries entre 0 et 2000 pieds
(0-610 m) seulement.)
ITEMS REQUIRED FOR INSTALLATION
External regulator (for propane/L.P.G. only)
Piping which complies with local codes
Pipe sealant approved for use with
propane/L.P.G. (resistant to sulfur compounds)
Manual shutoff valve
Sediment trap (see page 23)
Tee joint
Pipe wrench
Phillips head screwdriver
7/16-inch wrench
Other parts as required by local code
Safety Glasses
Gloves
PACKING LIST
1-Stowe Gas-Fired Heater
4-Decorative Ceramic Logs
1-Bag Charcoal Embers Only
1-Bag Charcoal Embers
1-Bag Platinum Bright Embers
1-Owner’s Manual
1-Thermostat
1-40’ Thermostat wire
1-L.P. Fuel Conversion Kit
1-Warranty Validation Form
1-Exhaust Restrictor Plate with Mounting Screw
2- Decorative Caps
The two screws holding the top of the front
on are for shipping purposes only. Once the
stove has arrived at the final destination
remove these two screws and replace them
with the two decorative caps provided with
the unit.
Note: Vent kits and components are supplied
separately. Failure to use the venting
components suggested by Hearthstone will
void your warranty.
UNPACKING AND INSPECTION
The Stowe is packaged by Hearthstone to withstand
normal shipment without damage. However,
damage can still occur during transit; so take care to
inspect for damage when unpacking and installing
the unit. If any damage or missing parts are
detected, immediately contact your dealer.
DO NOT INSTALL, OR PUT INTO SERVICE, A
DAMAGED OR INCOMPLETE HEATER.
CAUTION: THE TOP GRILL IS NOT CEMENTED,
OR OTHERWISE PERMANENTLY FASTENED IN
PLACE!
We recommend your Stowe be moved into place,
venting attached, gas and electrical connections
8

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
made, and any accessory blower installed before
installing the top grille.
Inspect the Stowe for visible or concealed damage.
The unit should appear to be square and true. The
sheet metal parts should be smooth and free of
bends and dents. The enameled cast iron should be
free of chips or cracks. If visible or concealed
damage is found, or suspected, contact your dealer
for instructions.
With the accessory box removed and set aside,
undo the lag bolts that fasten the unit to the pallet.
Take care not to mar or chip the enameled legs.
Have someone help lift the stove off the pallet and
set it into place.
The decorative ceramic logs supplied with the Stowe
are contained within the firebox. Always use great
care when handling the decorative ceramic fire logs,
as they are fragile and subject to damage and
breakage if handled roughly. Open the firebox door
and inspect the logs for damage. If a broken log is
encountered, contact your dealer for replacement
logs. Otherwise, set the logs aside until called for
during the installation.
FIREBOX ACCESS
To open the firebox:
1. Remove the two upper front screws (located in
the grill of the front) that hold the cast façade
onto the unit. (These screws ship on the unit
for transit purposes only and are removed
during installation.)
2. Open the valve access door by pulling the ash
lip out off the magnet and down. Allow the door
to swing down completely.
Figure 2: Façade Spring Latch Detail
3. Grasp the handle of the spring latch, located in
the center of the opening, pull out towards you
and then move the handle to the right to
disengage the catch, then release tension on the
latch - be careful not to drop the front as the
latch is unfastened. Be careful not to chip the
enamel when handling the front façade.
4. Grasp the bottom of the façade, lift it up slightly
and out off the L-brackets. Lower the façade and
move it away from the unit - set aside
5. To remove the glass, reach over the firebox, and
under the front grill. With a flat screwdriver, pry
the retaining clips up. There are two separate
clips. Be careful, when you lift the last one, as it
will free the glass and frame from the unit.
Note: The two screws holding the top of the front
on are for shipping purposes only. Once the stove
has arrived at the final destination, remove these
two screws and replace them with the two
decorative caps provided with the unit.
6. To re-install – reverse the outlined steps above.
HEARTH &FLOOR PROTECTION
The Stowe may be placed on any non-combustible
surface or wood floor. For placement of the Stowe
on carpeting, vinyl tile or other combustible
materials, the appliance must be installed on a metal
or wood panel extending the full width and depth of
the appliance. Installations must meet local codes.
CLEARANCE TO COMBUSTIBLES
Due to high surface temperatures, the unit should be
located out of traffic, and away from furniture and
draperies. Clothing and other flammable material
should not be placed on or near the heater. When
positioning the unit always maintain adequate
clearances around air openings into the combustion
chamber and allow for adequate ventilation.
Minimum clearances to combustibles must be
maintained as shown in figures 3 through 7.
L-Bracket (2)
Catch
Note: The rear clearance to combustibles is
determined by either the unit’s, or the vent pipe’s
minimum clearance, depending on whether the
installation calls for vertical rise within the room
or a rear exit, through-the-wall vent pipe.
Latch Handle
Ensure you consider the need for access to the gas
control valve access door on the front of the unit as
well as full access for periodic cleaning and
servicing. Also consider the location of the Optional
Blower Fan.
9

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
10
CAUTION: THESE CLEARANCES REPRESENT
MINIMUM DISTANCES IN ALL CASES, WHICH,
THROUGH TESTING IN AN INDEPENDENT
LABORATORY TO ANSI AND CSA STANDARDS,
WILL PREVENT FIRE OR SPONTANEOUS
COMBUSTION. WE DO NOT CONTROL THE
COMBUSTIBLE MATERIALS EXPOSED TO HEAT
BY THIS PRODUCT; THEREFORE, AN
ASSESSMENT MUST BE MADE BY THE
INSTALLER TO PREVENT CONSEQUENTIAL
DAMAGE OF WALLS AND FLOORING.
THE CORNER CLEARANCE FOR THE STOWE IS
2”, TO BE MEASURED FROM THE EDGE OF THE
TOP CASTINGS, TO THE ADJACENT WALL.
Figure 5: Snorkel-Mantle Clearance to
Combustibles
Figure 3: Minimum Venting-Mantle Clearance to
Combustibles
Figure 6: Snorkel-Wall Clearance to
Combustibles
Figure 7: Minimum Alcove Dimensions
Figure 4: Minimum Venting-Wall Clearance to
Combustibles

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
Acceptable Direct-Vent TERMINATION CAP LOCATIONS
Figure 8
11

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
VENTING INFORMATION
VENTING CONNECTION
Note: Starter collar is installed by Hearthstone.
1. The Stowe Direct Vent is approved for
installation only with the vent connecting
components listed on this page and Simpson
Dura-Vent Direct Vent GS, AmeriVent Direct,
EXCELDirect or Secure Vent systems. Use the
following instructions along with the pipe
manufacturer’s instructions to complete the
installation.
2. To attach the Restrictor Plate; see instructions
included with it. It will attach from inside the
firebox, after removal of the brick patterned
baffle. The two screws required are included in
the appliance. Be sure you can see the screw
head for future adjustments.
Note: For minimum venting configurations,
discard the restriction plate- see section
“Approved Vertical Termination Venting
Configurations”
3. Install the rest of the vent system according to
the manufacturer’s instructions.
Figure 9: Gasket & Stove Adapter Installation
Figure 7: Key
1. Restriction Plate 5950-922
2. Gasket 4” 3160-155
3. Inner starter 924H1
4. Gasket 6” 3160-157
5. Outer Starter 924H1
Figure 9: Starter collar and Restriction Plate
assembly
12

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
RESTRICTION PLATE
The restriction plate is used to control the draft of the
heater. Controlling the draft also changes the
aesthetics of the flame. The restriction plate has
eight settings, one (1) being the lowest and eight (8)
being the highest. For a fast moving flame with lots
of action, use a low setting. For a slow, lazy flame, a
high setting should be used. See Figure 11 for
instructions on how to adjust the restriction plate
settings.
RESTRICTION PLATE POSITION
A vent restriction plate is available for the appliance
to adjust the flow rate of exhaust gases. This insures
proper flames for the wide variety of vent
configurations, and efficiency. The restriction plate
consists of a rotating shutter below the starter
section of pipe and an adjustment plate with index
holes used to hold the shutter in a fixed position.
Depending on the vent configuration, you may be
required to adjust the restriction plate position. Refer
to figures 12 - 15 for positioning of the restriction
plate.
ADJUSTMENT TO RESTRICTION PLATE
Remove the log set before adjusting the restriction
plate by following the log set removal instructions on
page 25. Make sure the unit is cool before touching
any part of the firebox and log set. Remove the
exhaust baffle by removing the one screw in the
center of the baffle (refer to Figure 8). The baffle will
come out once the screw is removed. Be careful not
to drop the baffle on the pan burner. Once the baffle
is set aside, check the restriction plate screw
location. There are eight locations that the restriction
plate can be positioned. (Refer to Venting
Configuration – Figures 14 – 16 for recommended
restriction plate positions) (Refer to Figure 11 for
proper adjustment plate index location) ‘A’ in Figure
11 shows the locating screw that determines the
position of the plate.
NOTE: These positions are based on lab
results and can have some variance.
Remove the screw and position the restriction plate
in the desired location. Fasten the screw into the
proper hole and tighten. Reinstall the exhaust baffle
by setting the back edge of the baffle into the baffle
clip attached to the back wall of the firebox. Then
push the baffle against the heat exchanger and
reinstall the screw. Reinstall the log set and ember
strip as described in the log set installation
procedure on page 25.
Figure 10: Baffle Removal
Figure 11: Restriction Plate Adjustments
VENTING COMPONENTS &
CONFIGURATION
The Stowe cannot be vented jointly with any other
solid fuel or gas appliance. It must be vented directly
to the outside of the building using a proper
termination as listed in the manual. The only type of
venting pipe approved for use with your Stowe
Direct-Vent stove is Simpson Dura-Vent’s GS,
AmeriVent Direct, EXCELDirect and Secure Vent
Direct-Vent Pipe. The venting configurations are
shown in Figures 12 - 17. After determining the
venting configuration for your stove, select the vent
system that will accommodate your installation.
CAUTION: ENSURE ALL STOVE AND
TERMINATION CAP CLEARANCES ARE
OBSERVED PER THE OWNER’S MANUAL.
13

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
14
CAUTION: ENSURE THERE IS NO WIRING OR
PLUMBING IN THE CHOSEN LOCATION.
CAUTION: VENTING TERMINALS SHALL NOT BE
RECESSED INTO A WALL OR SIDING.
Note: If further direction is needed for
installation, please refer to the venting
instructions, which are provided with the venting
components.
ACCEPTABLE DIRECT-VENT TERMINATION CAP
LOCATIONS
The vent/air intake termination clearances above the
high side of an angled roof are as follows:
Roof Pitch Feet Meters
Flat to 6/12 1 0.3
7/12 to 9/12 2 0.6
10/12 to 12/12 4 1.2
13/12 to 16/12 6 1.8
17/12 to 21/12 8 2.4
Listed are Simpson Dura-Vent, AmeriVent Direct,
EXCELDirect and Secure Vent components
acceptable for installation, along with the minimum
venting kit available. The venting system must be
comprised of the appropriate venting components as
specified.
APPROVED VENTING SYSTEM COMPONENTS
900 Elbow
450 Elbow
6" Straight
9" Straight (Simpson only)
12" Straight
24" Straight
36" Straight
48" Straight
11"-14 5/8" Adjustable Pipe Length
Horizontal Vent Cap
Vertical Vent Cap
14” Snorkel
Vinyl Siding Standoff 4 x 6 5/8"
Round Ceiling Support Wall
Thimble Covers
Wall thimble
CHIMNEY LINER SYSTEM
1. Direct-Vent Chimney Liner Termination Kit
2. Chimney Liner Flex
3. Co-Linear Flex Connector
4. Co-Axial to Co-Linear Appliance Connect
MINIMUM VENT KIT
*Hearthstone Stove Starter Collar
45º Elbow
90º Elbow
(2) 9” Straight
Round Ceiling Support
Wall Thimble Cover
Wall Thimble
Horizontal Vent Cap
*Supplied and pre-installed by Hearthstone

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
Any centerlines shown are approximate. Please dry fit your venting and take measurements. Pipe
dimensions will vary by manufacturer and supplier.
See installation instructions on page 20.
Figure 12: Components for a Typical Snorkel
Installation
Figure 13: Components for a Typical Minimum
Horizontal Venting Installation
APPROVED VERTICAL TERMINATION VENTING CONFIGURATIONS*
*With No Elbows or (2) 45º Offsets (Figure 14), and (2) 90º Elbows (Figure 15)
10’ minimum system height (with or without offsets)
35’ maximum system height
6’ maximum offset (refer to Figure 14)
12’ maximum offset (refer to Figure 15)
The termination must fall within the outline shown in Figures 14 & 15. Use the indicated restriction plate
position. The restriction Plate part # is 5950-922.
PIPE CLEARANCES TO COMBUSTIBLES
1” to vertical runs
1” below and to the side of horizontal runs
2” from the top of horizontal runs
15

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
Figure 14: Vertical Straight Pipe Terminations
16

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
17
Figure 15: Vertical Terminations Using (2) 90º Elbows

Hearthstone Quality Home Heating Products, Inc. Stowe Model 8321
APPROVED VENTING CONFIGURATION FOR
HORIZONTAL TERMINATION*
*(1) 90º Elbow
The termination must fall within the area outlined
by the shaded area shown in the illustration
below.
A minimum of a 9” rise is required directly off the
heater.
Use a vinyl siding standoff when installing
against vinyl siding.
Horizontal sections require a ¼” rise every 12” of
horizontal run.
NOTES:
1. The vent must terminate within one of the
regions outlined by the shaded area.
2. For each 90º elbow after 2, remove 5’ from
horizontal run.
3. For Canadian installations: remove 4’
from horizontal run.
4. At minimum vertical rise, maximum
horizontal run 14”.
5. Use with snorkel termination 14” maximum
horizontal run.
Figure 16: Horizontal Termination
18