HearthStone Sterling-Ht 8532 Troubleshooting guide

Sterling Ht Model 8532
Manual: 6400-40428
Revised: 10/21/09
Sterling-Ht (Model 8532)
GAS-FIRED DIRECT VENT HEATER
Owner’s Manual & Installation Guide
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-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 dos incendies.
L’installation et service doit être exécuté par un
qualifié installer, agence de service ou le
fournisseur de gaz.

Hearthstone Quality Home Heating Products, Inc STERLING-Ht Model 8532
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INFORMATION SHEET
Use this page to record all relevant information concerning the purchase, installation, and maintenance of your
STERLING Ht Model 8532 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

Hearthstone Quality Home Heating Products, Inc STERLING-Ht Model 8532
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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
E-mail: [e-mail]
Web: www.Hearthstonestoves.com
TABLE OF CONTENTS
WELCOME .................................................. 2
OWNER’S INFORMATION............................ 4
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 THE FIRST TIME..... 19
ODORS AND IMPURITIES.................................19
PREPARE FOR LIGHTING.................................19
INITIAL ADJUSTMENTS...................................19
LIGHTING INSTRUCTIONS...............................19
TURNING OFF THE UNIT.................................20
PILOT AND BURNER FLAMES ......... 20
VARIABLE OUTPUT CONTROL........................20
GAS CONVERSIONS................................... 21
ROUTINE MAINTENANCE AND CARE ....... 22
PARTS LISTS ............................................. 24
TROUBLESHOOTING GUIDE ..................26
LIMITED WARRANTIES...........................29

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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. Clothing or other
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 by a licensed or qualified service
person. Only open front for routine
service. Do not slam, or strike the glass.
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
imperative 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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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.)
Warning: 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
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 igniter 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 can easily operate 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)

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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.)
FIBER LOG SAFETY INFORMATION
If the decorative fiber logs supplied with the Sterling
are damaged, they must be replaced. The
manufacturer, through your local Hearthstone dealer,
supplies replacement parts. Do not replace fiber 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 fiber logs supplied with the Sterling
are located in the firebox. Always use great care
when handling the decorative fiber 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 Fiber Logs
1- Bag Platinum Bright Embers
1-AA Battery
1-Owner’s Manual and Warranty Card
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
4" (102mm)
2" (51mm)
Parallel Installations 1" (26mm)
2" (51mm)
Mantel Installations
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 7 13

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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™
•EXCELDirect
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 6 5/8”
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 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
TerminationClearances
Horizontal
Overhang
Termination
Cap
Vertical Wall

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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.

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D. Vertical Terminations - Straight or (2) 45OElbows (4"x 6” Pipe Only)

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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 ensure 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

HearthStone Quality Home Heating Products Inc STERLING Ht Gas-Fired Direct Vent heater
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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.
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
Conditionally approved for purchased mobile home
installation. This appliance may be installed in an
aftermarket permanently located, manufactured
(mobile) home, except 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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17
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 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 fiber 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 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 (soot); 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.
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
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HearthStone Quality Home Heating Products Inc STERLING Ht Gas-Fired Direct Vent heater
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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) Open the bag of Platinum Bright Embers. Fluff
up the pieces, and spread randomly over the logs
and burners. These embers will glow brightly
when the unit is running.
7) 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
Caution
Log set retains heat and can be very hot, if
previously lit! Allow 1 hour after pilot light is turned
off before handling.
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 THE
FIRST TIME
CAUTION: Lighting the Sterling-Ht for the
first time and adjustments to the unit should
be performed only by qualified service
personnel.
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.
ODORS AND IMPURITIES
A heater of this type may produce odors during
heater operation due to impurities that may exist in
the immediate area. Sources of impurities can be
cleaning solvents, paint solvents, cigarettes, smoke,
soot from scented candles, pet hair, dust, adhesives,
new carpet, and/or textiles. Such odors will dissipate.
However, opening a window or otherwise providing
additional ventilation to the area can alleviate the
condition. If any odor persists, contact your dealer or
an authorized service technician.
PILOT LIGHT
The Sterling has a battery operated electric spark
igniter, which ignites the pilot light by means of a
spark at the pilot light assembly. To activate the
igniter, turn the gas control knob to ‘Pilot’ and push
and hold it down. You must install the included
battery for the igniter. The battery compartment is
located 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 electric spark.
PREPARE FOR LIGHTING
Prepare for the lighting procedure by adjusting the
thermostat to its lowest setting or OFF position. If the
gas control knob is not in the OFF position, turn the
knob fully clockwise to OFF. Locate the variable
output control knob and turn it fully counter-
clockwise to the highest setting.
INITIAL ADJUSTMENTS
Once the Sterling-Ht is set in place, connected and
assembled as described in the Assembly of the Unit,
Electrical Connections, and Gas Supply &
Connections sections of this manual, the unit is ready
to be lit for the first time. Each unit is tested prior to
shipment by the manufacturer, so ignition should take
place without failure. However, a number of small
adjustments may be necessary to compensate for
variations in gas pressure, altitude, and other factors
particular to each installation.
Prior to lighting the unit for the first time, wait 5
minutes to allow any residual gas within the unit to
dissipate. Smell all around the appliance area for gas.
Be sure to smell next to the floor because some gases
(LP) are heavier than air and will settle on the floor.
If you do not smell gas after this five-minute period,
proceed with the lighting procedure. If you do smell
gas, do not proceed with the lighting procedure.
Instead, immediately refer to the What to Do If
You Smell Gas Warning, on the cover of this
manual.
LIGHTING INSTRUCTIONS
The gas control knobs are located at the top, right
rear corner of the unit (see diagram on next page).
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 igniter in the
firebox) Verify ignition of the pilot. Continue to
hold the control knob in for about 20 seconds
after the pilot is lit (ensures thermocouple is up to
temperature). 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.