HearthStone Sterling-Ht 8532 Troubleshooting guide

Owner’s Manual & Installation Guide
for the Sterling-Ht(8532)
GAS-FIRED DIRECT VENT HEATER
READ THIS OWNER’S
MANUAL
Operate and maintain this gas heater according to
this instruction manual.
Read This Manual In Its Entirety.
WARNING: If the information in these instructions
is not followed exactly, a fire, or explosion may
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.
In the Commonwealth of Massachusetts, all
installation of gas lines and gas fitting shall only
be done by a licensed gas fitter or licensed
plumber.
AVERTISSEMENT: Assurez-vousdebiensuivre les
instructionsdonné dans cettenotice pourréduireau
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 dos incendies.
L’instal
lation et service doit être exécuté par un
qualifié installer, agence de service ou le
fournisseur de gaz.
01-04-2005 Model # 8532
317 Stafford Avenue,
Morrisville, Vermont 05661-8695
E-Mail: [email protected].

HearthStone Quality Home Heating Products, Inc STERLING-Ht Gas-Fired Direct Vent heater
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INFORMATION SHEET
Use this page to record all relevant information concerning the purchase, installation, and maintenance of your
STERLING Ht Gas-Fired 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 (check one) Natural Gas Liquid Propane
Sold by:
Phone: Date of Purchase:
Installed by:
Phone: Date of Installation:
Gas Supplier:
Phone:
Read this Owner’s Manual before installing, or operating the STERLING heater. Retain this manual for future
reference.
SERVICE RECORD
Date Who Performed Work Work Performed Notes:
WHAT WHEN
Firebox Cleaning............. annually
Glass Cleaning................ as needed
Door Gasket.................... Replacement as needed

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WELCOME
Congratulations on your purchase of HearthStone’s
Sterling Ht Gas-Fired Direct Vent heater. The
Sterling incorporates the latest in balanced vent gas
technology, which will provide you with clean,
efficient heat for years to come. Combustion air
comes directly from the outside of your home to the
sealed firebox system, eliminating the potential for
annoying back drafts or other problems associated
with home depressurization. The combination of
natural stones with cast iron gives the Sterling a
pleasing look, which can be maintained with
minimum care.
The Sterling will provide you with years of practical
and convenient service. However, as with any gas
appliance, the unit must be properly and safely
installed and maintained by qualified service
personnel to ensure safe and trouble-free operation.
READ THIS OWNER’S MANUAL
Operate and maintain this gas heater according to the
instructions in this manual. 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.
ALWAYS VENT TO THE OUTSIDE
Never vent the gas heater to other rooms, or
buildings. Do not connect this gas appliance to a
chimney flue serving a separate solid-fuel burning
appliance.
MANUFACTURED BY:
HearthStone Quality Home Heating Products, Inc.
317 Stafford Avenue
Morrisville, Vermont 05661-8695
USA
TABLE OF CONTENTS
WELCOME...................................................2
OWNER’S INFORMATION............................3
LIGHTING INSTRUCTIONS .................................4
DAILY OPERATIONS.........................................4
INSTALLER’S INFORMATION ......................5
UNPACKING AND INSPECTION ..........................5
STOVE DIMENSIONS & CLEARANCES TO
COMBUSTIBLES ................................................6
VENTING INFORMATION.............................9
ATTACHING YOUR VENTING..........................15
GAS CONNECTIONS ..................................16
LOG PLACEMENT ...........................................17
INSTALLATION OF THE LOG SET.....................17
REMOVAL OF THE LOG SET ............................18
LIGHTING THE UNIT FOR THE FIRST TIME19
INITIAL ADJUSTMENTS...................................19
GAS CONVERSIONS...................................20
ROUTINE MAINTENANCE AND CARE.......20
PARTS LISTS .............................................22
TROUBLESHOOTING GUIDE ..................24
LIMITED WARRANTIES............27

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SERVICE CAUTION
Any shield, door, or other component removed for
servicing must be replaced prior to operating. Any
components of the stove removed for servicing must
be replaced prior to operating. If you believe your
Sterling is not performing properly, immediately
discontinue operation until the unit has been
inspected and approved by qualified service
personnel. Prior to servicing the unit, turn the valve
control knob clockwise to “OFF”. Ensure the unit is
cool before servicing and cleaning. Any safety
screen, guard, or component removed during
servicing must be replaced before operation. Do
not use any components other than those approved
by HearthStone Quality Home Heating Products,
Inc., otherwise all warranties are void. Do not
substitute components!
FIRE HAZARD
Do not store or use gasoline, or other flammable
vapors or liquids near this appliance. The Sterling
should be located out of traffic, and away from
furniture, draperies, clothing, and other flammable
materials.
SHOCK HAZARD (IF EQUIPPED WITH ACCESSORY FAN) The
accessory blower 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.
HOT SURFACES
Certain exposed surfaces of the Sterling 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 should be located out of traffic and
away from furniture, draperies, clothing, and
other flammable materials. Children and adults
should be alerted to the hazards of high surface
temperatures and must stay away to avoid burns
to skin or possible clothing ignition. Ensure that
young children are carefully supervised when in
the same room as the appliance.Clothingorother
flammable material must not be placed 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.
•WARNING: do not operate the appliance
with the front glass removed, cracked, or
broken. Replacement of glass should be done
bya licensed or qualified service person. Only
open front for routine service. Do not slam, or
strike the glass.
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 part has been under
water. Immediately call a qualified service technician
to inspect the heater, and to replace any part of the
control system that has been under water. (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.)
Certified for use by:
Board of State Examiners of Plumbers and Gasfitters
100 Cambridge Street, Room 1511
Boston, Massachusetts 02202
WARNING!
A qualified service
technician should do
installation, and repair. A qualified service
technician must inspect the appliance before
use, and at least annually. More frequent
cleaning may be required due to excessive lint
from carpeting, bedding material, pets, etc. It
is impe
rative that the control compartments,
burners, and circulating air passages of the
appliance are kept clean and free of
obstructions.
(S’assurer que le brûleur et le
compartiment des commandes sont propres.
Voir les instructions d’installation et
d’utilisation qui accompagnent l’appareil.)

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LIGHTING INSTRUCTIONS
The gas control knob is located on the top of the
stove, in the rear, right-hand corner.
1. Set the on/off/T-stat switch or thermostat to the
off position.
2. Unplug the blower accessory, if so equipped
3. Push in and turn gas control knob clockwise to
“OFF”. (If not previously lit, the knob should be
in this position.)
4.Wait (5) five minutes to clear out any gas. If you
then smell gas, STOP! Smell all around the
appliance area for gas. Be sure to smell next to
the floor because some gases (LPG) are heavier
than air and will settle on the floor. If you smell
gas immediately follow the What To Do If You
Smell Gas! warning on the cover of this Manual.
If you do not smell gas, go to the next step.
5. Turn gas control knob counterclockwise to
“PILOT”.
6. Push in control knob all the way and hold
in.(You should hear the clicking of the piezo
ignitor in the firebox) Verify ignition of the pilot.
Continue to hold the control knob in for about 20
seconds after the pilot is lit. Release the knob
and it will pop back out. Pilot should remain lit.
If the pilot goes out, repeat the operation.
•If knob does not pop out when released, stop
and immediately call a qualified service
technician or gas supplier.
•If the pilot will not stay lit after several tries,
turn the gas control knob “OFF” and call a
qualified service technician or gas supplier.
7. Turn gas control knob counterclockwise to
“ON”.
8. Select “ON” or “T-STAT” position on the
on/off/t-stat switch.
9. Plug in the blower accessory, if so equipped.
10. Set thermostat to “ON” and set the desired
temperature setting.
Normally, if the “T-STAT” position was selected, the
main burner is cycled on and off by the Thermostat
or the “on”, “off” switch located on the bottom of the
Thermostat body.
TO TURN OFF THE GAS TO THE APPLIANCE
Turn the gas control knob clockwise to “OFF”
position. If shutting the unit off for the non-heating
season, this will improve the overall efficiency of the
unit as the heat from the pilot is wasted in the
summer. When putting the unit back into service
follow the lighting instructions described on this
page.
VARIABLE OUTPUT CONTROL
The gas control valve is equipped with a variable
output control. This control varies the rate of heat
produced by the unit by varying the gas pressure to
the ember burner.
DAILY OPERATIONS
The homeowner easily operates the Sterling gas-fired
heater. The unit comes with a standard thermostat.
Remote thermostats, or wall switches are available
for purchase from your local HearthStone dealer.
Once the thermostat is installed and properly
adjusted, the desired room temperature is maintained.
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. Also available is a variable speed blower.
(Kit# 95-57320)

HearthStone Quality Home Heating Products, Inc STERLING-Ht Gas-Fired Direct Vent heater
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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, which can be obtained from:
AMERICAN NATIONAL STANDARDS
INSTITUTE, INC.
1430 BROADWAY
NEW YORK, NY 10018
OR
NATIONAL FIRE PROTECTION
ASSOCIATION, INC.
BATTERY MARCH PARK
QUINCY, MA 02269
The appliance, when 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 with 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.)
CERAMIC FIBER LOG SAFETY INFORMATION
If the decorative ceramic logs supplied with the
Sterling are damaged, they must be replaced. The
manufacturer, through your local HearthStone dealer,
supplies replacement parts. Do not replace ceramic
logs with any materials not approved by HearthStone
Quality Home Heating Products, Inc.
UNPACKING AND INSPECTION
Unpack and Inspect for Damage
The Sterling is packaged by the manufacturer 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 a missing part, is
detected, immediately contact your dealer. Do not
install or put into service a damaged or incomplete
heater.
The unit should appear to be square and level. The
sheet metal parts should be smooth and free of bends
or dents. The enameled cast iron should be free of
chips or cracks. If visible or concealed damage is
found, contact your dealer.
The decorative ceramic fiber logs supplied with the
Sterling are located in the firebox. Always use great
care when handling the decorative ceramic logs, as
they are very fragile and subject to damage and
breakage. To open the front, grasp both sides of the
front cast facade, toward the bottom, and lift upward
and then outward. The bottom will slide up and out.
The whole piece is then easily removed. Set the front
aside taking care not to chip or scratch the enamel.
Next, locate the two rotating clips above the glass.
Rotate the clips out of the “locked” position and tilt
the top of the glass outward. Lift the entire glass up
and out. The log set can now be inspected for
damage. To take the unit off the pallet, remove the
lag bolts, which fasten the unit to the pallet. Take
care not to chip the enameled legs. Have someone
help lift the stove off the pallet, and set it into place.
Packing List
1-Sterling Gas-fired Heater containing:
3-Decorative Ceramic Fiber Logs
1-AA Battery
1-Owner’s Manual and Warranty
1-Thermastat and wire
1-LP Conversion kit

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•WARNING! Do not operate the stove with
the glass front removed, cracked, or
broken.
ITEMS REQUIRED FOR INSTALLATION
* External regulator (for propane/L.P.G. only)
* Piping which complies with all codes
* Pipe sealant approved for use with propane/L.P.G.
(resistant to sulfur compounds)
* Manual shutoff valve
* Sediment trap (page 16)
* Tee joint
* Pipe wrench
* Phillips head screwdriver
* Other parts as required by local code
*Safety Glasses
*Gloves
*Stone Set
AIR SUPPLY
The Sterling Direct-vent does not require additional
installer provided ventilation.
STOVE DIMENSIONS & CLEARANCES TO
COMBUSTIBLES
Always maintain clearances around the stove, as
shown in the Clearances to Combustibles figures.
This allows for adequate ventilation.
Sterling Dimensions
If this appliance is to be installed on carpeting, vinyl
tile or combustible material other than wood flooring,
it must be installed on a metal or wood panel extending
the full width and depth of the stove.

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18" (458mm)
3" (76mm)
14" (355mm)
3" (76mm)
Corner Installations
2" (51mm)
Floor Alcove or Mantel Installations
4" (102mm)
2" (51mm)
Parallel Installations 1" (26mm)
2" (51mm)
CLEARANCE TO COMBUSTIBLES
SPECIFICATIONS:
LISTED: DIRECT VENT GAS HEATER
Model: 8532-Sterling Ht DV
Testing Agency: Intertek Testing Services NA, Inc. (ITS)
Tested to: ANSI Z21.88-1998•CSA 2.33-M98 CAN/CGA 2.17
* You may keep your orifices the same if you wish to burn at the lower 33,000 btus with the top exit kit.
Venting Exit Type
Rear Exit –5”x8”
Pipe *Top Exit –4”x6” Pipe
Gas Type
NG LP NG LP
Input rating (Btu/hr) 0-
2000ft
33,000 33,000 38,000 38,000
Maximum output (Btu/hr) 0-2000ft 26,600 27,400 30,200 31,300
Minimum input rating (Btu/hr)
13,600 11,900 13,900 11,600
Orifice size DMS 0-2000ft 43,52 55,63 38,51 53,63
Man. pressure-HI setting (in.w.c./kPa) 3.5/0.87 10.0/2.48 3.5/0.87 10.0/2.48
Man. pressure-LO setting (in.w.c./kPa) 1.2/0.3 3.3/0.8 1.2/0.3 3.3/0.8
Minimum inlet pressure (in.w.c./kPa.) 5.0/1.24 11.0/2.88 5.0/1.24 11.0/2.88
Maximum inlet pressure (in.w.c.) 7.0 13 713

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VENTING INFORMATION
The Sterling is approved for installation only
with the following venting manuafcturers
products.
•Simpson Dura-vent Direct Vent GS
•AmeriVent Direct
•Secure Vent systems
•Selkirk Direct-Temp™
WARNING
This appliance must not be connected to a chimney
flue serving a separate solid-fuel burning appliance.
The Sterling can be vented two ways:
A) Straight out the back exit, using 5”x8” pipe.
B) Top exit, using kit #95-60320. If you want to
run your vent vertically, you must buy this
vertical vent kit which will convert the venting
pipe to 4"x6". The restrictor will be part of this
kit. No restrictor is needed for a horizontal
exit.
When referring to the rest of this section ensure
which way your unit is being vented.
APPROVED VENTING SYSTEM COMPONENTS
Component Description
900 Elbow
450 Elbow
6" Straight
9" Straight
12" Straight
24" Straight
36" Straight
48" Straight
11"-14 5/8" Adjustable Pipe Length
Horizontal Vent Cap
Vertical Vent Cap
Snorkel 36”
Vinyl Siding Standoff 4 x 65/8”
Round Ceiling Support Wall
Thimble Covers
Wall thimble
If the vent air intake system, for any reason, is
disassembled, it must be reinstalled per the
instructions provided for in the initial installation.
Allowable Venting Configuration Graphs
When determining the venting configuration, you
must consider the position of the termination cap.
There are 5 possible categories.
A) Fireplace & Existing chimney
installation
B) Horizontal termination for 5”x8” pipe
C) Horizontal termination for 4”x6” pipe
D) Vertical termination straight or 2 45O
elbows (4”x6” pipe only)
E) Vertical termination, 1 or 2 90O elbows
(4”x6” pipe only)
Every venting configuration must fall into one of
these categories.
The vent/air intake termination clearances above the
high side of an angled roof as follows:
The termination cap must not
be recessed into a wall or
ceiling
Note:
If the unit is vented vertically, 4”x6” pipe
must be used.
If using Top Exit Kit, a 24” section of pipe
must be used directly off of stove.
Roof Pitch
Feet
Meters
Flat to 6/12 10.3
7/12 to 9/12 20.6
10/12 to 12/12 41.2
13/12 to 16/12 61.8
17/12 to 21/12 82.4
TerminationClearances
Horizontal
Overhang
Termination
Cap
VerticalWall

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A. Fireplace & Existing Chimney Installation
The use of an existing chimney as an air intake is not covered under the ANSI Z21.88
-
1998•CSA
2.33-M98 test methods and the resulting ITS/WHI product certification. The code Authority
Having Jurisdiction must be consulted prior to proceeding with this installation method.

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B. Horizontal Terminations for 5"x 8" Pipe

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C. Horizontal Terminations for 4"x 6" Pipe (Requires the use of Top Exit Kit, # 95-60320)
Note: All top exit configurations require a minimum of a 24” section of pipe directly off the unit.
D. Vertical Terminations -Straight or (2) 45OElbows (4"x 6” Pipe Only)

HearthStone Quality Home Heating Products, Inc STERLING-Ht Gas-Fired Direct Vent heater
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E. Vertical Terminations -(1) or (2) 90OElbows (4"x 6" Pipe)

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ATTACHING YOUR VENTING
Follow the instructions in either of the 5”x8”
starter kits. If you are attaching the Top Exit kit,
(#95-60320) for vertical venting configurations,
the instructions will be provided with the kit.
INNER COLLAR:
Locate the 8 screw holes where the inner collar
attaches to the heat exchanger. Attach the inner
collar and gasket with the 8 screws provided
with the collar.
OUTER COLLAR:
Locate the 8 screw holes where the outer collar
attaches to the heat exchanger. Attach the outer
collar and gasket with the 8 screws provided
with the collar.
You are now ready to install your venting.
1. Gasket
2. Inner Starter
3. Gasket
4. Outer Starter
VENT RESTRICTOR
When converting the unit to a top exit, (4”x6”
pipe), a restrictor is supplied with the kit.
Instructions for installation of the restrictor are
supplied with the kit. To adjust your restrictor
for maximum flame appearance, first be sure the
unit is cool before touching any part of the stove
or venting. Refer to the Venting Configurations
for recommended restriction plate positions.
Loosen the Phillips head screw and rotate the
locator, found on the rear middle of the stove to
a position which corresponds to the appropriate
chart setting. Shown below are the approximate
locations of the settings 1-3, however it can be
set in any position. Tighten the screw in the
desired setting.
Note:
These positions are based on lab results and can
have some variance.
IF the vent-air intake system is disassembled for
any reason, reinstall per the instruction provided
for the initial installation.
The flow of combustion and ventilation air
must not be obstructed.
Restrictor Plate Setting
Locations

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Cet appareil peut être installé dans un maison
préfabriquée (mobile) déjà installée à demeure si les
règlements locaux le permettent.
Cet appareil doit être utilisé uniquement avec les
types de gas indiqués sur la plaque signalétique. Ne
pas l’utiliser avec d’autres gas sauf si un kitde
conversion certifié est installé
3"MIN.
Cap
Nipple
To Equipment
Inlet Tee Fitting
Gas Supply
Inlet
Sediment Trap is required
GAS CONNECTIONS
A top plate and a side cover must be removed to
access the gas control valve. First remove the gas
control valve knobs, by grasping the knobs firmly
and gently pulling straight up on the knobs. Next
remove the six screws holding the top plate on. Two
are located on the sides, and four are located on top.
To remove the side cover, loosen the two screws
which have holes in the side for accessing. Do not
remove these screws, just loosen them.. Slide the
side cover upward and remove. The gas supply line
connection is made to the Sterling’s gas control
valve, located on the back of the unit, in the lower
right corner, using a 3/8" NPT fitting. The pipe must
be sized to provide sufficient gas supply to meet the
maximum demand of the unit. The supply line must
include a manual shut-off valve and union so that the
unit can be disconnected for servicing.
Conditionally approved for purchased mobile
home installation. This appliance may be
installed in an aftermarket permanently
located, manufactured (mobile) home, where
prohibited by local codes.
This appliance is only for use with the type of
gas indicated on the rating plate. This
appliance is not convertible for use with other
gases, unless a certified kit is used, available
through your local HearthStone dealer.

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Use of a dedicated sediment trap is required by code,
and by Hearthstone. Damage to components caused
by the lack of a sediment trap is not covered by
warranty.
Once connected to the gas supply, the gas inlet
pressure, and manifold gas pressure, must be tested.
The gas control valve has built in pressure taps for
test gauge connections. The supply line pressure must
be tested to ensure it meets the minimum pressure for
the type of fuel in use (NG or LP).
Pressure Measurements: To measure the gas
pressures, connect a manometer to the gas inlet tap
(6) and manifold pressure tap (7) in the Valve
Description Figure.
GAS PRESSURE ADJUSTMENT
A qualified technician must connect the heater to the
gas supply, and leak test the unit before it is approved
for use. Consult all applicable codes. The appliance,
and its main gas valve, must be isolated from the gas
supply piping system by closing its individual manual
shutoff valve during any pressure testing of the gas
supply piping system at test pressures equal to or
greater than ½ psig (3.5kPa).
REPLACING THE GLASS
To replace the front glass, first shut the pilot light off.
Next remove the front cast and glass assembly, as
described in Installation of Log Set section. If the
glass is broken, pull the broken fragments of glass
away from the glass frame using heavy-duty gloves,
as the pieces will be very sharp. Carefully replace the
glass gasket as necessary, and replace the glass
assembly and front cast.
•WARNING! Do not use substitute materials.
Use only parts that have been supplied by
HearthStone, through an authorized
HearthStone dealer.
•CAUTION! Do not clean the glass while the
unit is hot. Allow approximately one hour
before attempting cleaning.
LOG PLACEMENT
Place only the decorative ceramic fiber log set
supplied with the unit in the firebox. This log set is
specifically designed to work with the provided
ember burner. Do not use any other type of ceramic
logs, wood logs, or other materials in the firebox. If
the original log set is damaged, or broken, contact
your HearthStone dealer for replacement. The
decorative ceramic fiber log set will last a long time,
however, they will break easily if subjected to rough
or improper handling.
Exact positioning of the log set is required in order to
obtain a pleasing flame pattern and efficient
combustion. Incorrect log placement can cause
carbon build-up; excess thermal stress on the log set
and stove parts, reduced efficiency, and high levels of
carbon monoxide. If the log set does not fit into the
firebox exactly as outlined, contact your dealer for
assistance.
INSTALLATION OF THE LOG SET
1) First remove the front cast and glass assembly.
To remove the front, grasp both sides of the
front cast facade, toward the bottom, and lift
upward and then outward. The bottom will slide
up and out. The whole piece is then easily
removed. Set the front aside taking care not to
chip or scratch the enamel. Next, locate the two
rotating clips above the glass. Rotate the clips
out of the “locked” position and tilt the top of
the glass outward. Lift the entire glass assembly
up and out.
2) Gently take the logs out of the firebox and
remove the bubble wrap from the log set. Be
careful not to damage the log set when
unpacking. There are three logs, a Right, a Left
and a “Twig”.
3) Gently place the Right Log (1) in the firebox, on
the ember burner. The right log has a portion of
twig on the top part of it. On the underside of
the log there is an “L-shaped” cutout that lines
up the log on the ember burner, in the
appropriate position. It should sit as shown.
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HearthStone Quality Home Heating Products Inc STERLING Ht Gas-Fired Direct Vent heater
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4) Gently place the Left Log (2) in the firebox, on
the ember burner. On the underside of the log
there is an “L-shaped” cutout that lines up the
log on the ember burner, in the appropriate
position. It should sit as shown.
5) Gently place the Twig Log (3) in the firebox, on
the ember burner and against the Right Log (1).
The twig sits in a recessed part of the ember
burner, which lines it up, in the appropriate
position. It should sit as shown.
6) Re-install the glass assembly by lining up the
three tabs on the bottom of the assembly with
the three slots on the firebox. Slide the lower
portion of the glass assembly into the slots and
push it flush against the firebox. Rotate the clips
into the “locked” position. Re-install the front
cast by sliding the upper portion under the lip of
the top and tilting the bottom in flush with the
glass assembly. It should then slide downward
and be snug in place. Make sure the glass
assembly is properly secured to the firebox
before turning the unit on. Be careful not to chip
the enamel when installing the glass assembly or
front cast.
REMOVAL OF THE LOG SET
To remove the log set, follow the Installation of
Log Set instructions in reverse. Place the logs and
in a safe area where they will not be damaged.
CAUTION
Fragile! Handle log set with care.
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LIGHTING THE UNIT FOR
THE FIRST TIME
SMOKE AND FUMES WARNING
When lit for the first time, the Sterling will emit some
smoke and fumes. This is normal “off-gassing” of
the paints and oils used in the manufacturing and
assembly of the unit. Open windows to vent the
room if necessary. The off gassing and fumes will
subside after the first 10 to 20 minutes of operation.
Once the Sterling has been set in place and connected
as described previously, the unit is ready to be lit for
the first time. The manufacturer tests each Sterling
prior to shipment, so ignition should take place
without failure.
Caution
Log set retains heat and can be very hot, if
previously lit! Allow 1 hour after pilot light is turned
off before handling.
PILOT LIGHT
The Sterling has a battery operated piezoelectric
spark igniter button located on the gas control valve,
on the top rear of the unit, which ignites the pilot
light by means of a spark at the pilot light assembly.
It is at this time you must locate and install the
battery into the ignitor. It is in the lower rear area of
the stove. Do not attempt to light the unit with a
match or by any means other than the piezoelectric
spark.
PILOT ADJUSTMENT
The pilot light is preset by the manufacturer and
should not need adjustment. The pilot light flame
must be large enough to engulf the thermopile and
thermocouple located next to the pilot, but not so
large as to create excessive noise or consume
excessive gas. (refer to the figure on this page)
However, it can be adjusted by means of the pilot
light adjustment screw located on the gas control
valve. Access the gas control valve as described in
the Gas Connections section, on page 16. Note that
the pilot flame must engulf the thermopile so that the
thermopile can generate sufficient milli-voltage (325
to 500-mv) to power the millivolt gas control valve
Before lighting, smell all around the appliance area
for gas. Be sure to smell next to the floor because
some gases (LPG) are heavier than air and will settle
on the floor. If you smell gas, check for leaks. Use
only your hand to turn the gas control knob. Never
use tools.
•WARNING! The control has an interlock
device. If the stove has been lit, it will not
relight immediately. After shutting off all
gas flow, the pilot burner cannot be relit
until the thermocouple has cooled,
allowing the electromagnet to be released
(Approx. 60 sec.). The gas control knob is
designed to operated by hand. Do not use
any tools during this operation.
•
INITIAL ADJUSTMENTS
AIR SHUTTER
The air shutter is preset by the manufacturer for
optimum operation and should not need adjustment.
However, it may need adjustment once the unit has
been installed to compensate for variations in supply
line pressure, altitude, and other variables. The air
shutter is used to regulate the air-to-gas combustion
mixture, which in turn adjusts the size and color of
the flames.
AIR SHUTTER ADJUSTMENTS
The air shutter is adjustable while the stove is
burning. The two air shutters on the ember burner