Monessen Hearth Direct Vent Gas Fireplace MDV500 User manual

MDV SERIES
DIRECT VENT GAS FIREPLACE
INSTALLATION AND OPERATING
INSTRUCTIONS
MODELS: MDV500 and MDV600
READ BEFORE INSTALLING. SAVE THESE INSTRUCTIONS
WARNINGS
DUE TO HIGH TEMPERATURES, THE
APPLIANCE SHOULD BE LOCATED OUT OF
TRAFFIC AND AWAY FROM FURNITURE AND
DRAPERIES.
CHILDREN AND ADULTS SHOULD BE
ALERTED TO THE HAZARDS OF HIGH
SURFACE TEMPERATURE AND SHOULD
STAY AWAY TO AVOID BURNS OR CLOTHING
IGNITION.
YOUNG CHILDREN SHOULD BE SUPERVISED
WHEN THEY ARE IN THE SAME ROOM AS
THE APPLIANCE.
CLOTHING OR OTHER FLAMMABLE
MATERIAL SHOULD NOT BE PLACED ON
OR NEAR THE APPLIANCE.
KEEP THE ROOM AREA CLEAR AND
FREE FROM COMBUSTIBLE MATERIALS,
GASOLINE, AND OTHER FLAMMABLE
VAPORS AND LIQUIDS.
WARNINGS
IF THE INFORMATION IN THESE INSTRUCTIONS ARE
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 in the vicinity of this or any other
appliance.
– WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any
phone in your building.
• Immediately call your gas supplier from a
neighbor's phone. Follow the gas supplier's
instructions.
• If you cannot reach your gas supplier, call the fire
department.
– Installation and service must be performed
by a qualified installer, service agency or the
gas supplier.
WARNING: Improper installation, adjustment, alteration,
services or maintenance can cause injury or property
damage. Refer to this manual. For assistance or
additional information consult a qualified installer,
service agency or the gas supplier.
This appliance may be installed in an OEM installation
in manufactured home (USA only) or mobile home and
must be installed in accordance with the manufacturer's
instructions and the manufactured home construction
and safety standard, Title 24 CFR, Part 3280 or Standard
for Installation in Mobile Homes. CAN/CSA Z3-240MH.
This appliance is only for use with the type(s) of gas
indicated on the rating plate unless a certified kit is
used.

275D2523
CONTENTS
Important Safety Information .......................... 3
Product Features.............................................. 5
Code Approval.................................................. 5
Pre-Installation Information............................. 6
Installing Above 2000 Feet............................ 6
Orifice Sizes, Pressures and BTUs............... 6
Before You Start............................................ 6
Fireplace Framing ......................................... 7
Fireplace Dimensions.................................... 8
Fireplace Location......................................... 9
Securing Fireplace to Floor or Framing ....... 10
Clearances ...................................................... 11
Installation Information.................................. 12
Vent Installation.............................................. 13
Installation Precautions............................... 13
Optional Top Vent Application..................... 14
Installation Planning.................................... 15
Installation for Vertical Termination............. 15
For Horizontal Termination.......................... 16
How to Use a Vent Graph ........................... 17
Rear Wall Vent Installation.......................... 18
Horizontal (Through-the-Wall) Termination
Configurations............................................. 21
Horizontal with Vertical Rise
(Through-the-Wall) Applications.................. 22
Below Grade Installation ............................. 23
Vertical Through-the-Roof Installation......... 24
Installation for Vertical Termination............. 26
Flat Ceiling Installation................................ 26
Fireplace Installation...................................... 28
Check Gas Type ......................................... 28
Installing Gas Piping to Fireplace Location. 28
Checking Gas Pressure ................................. 30
Electrical Installation...................................... 31
Electrical Wiring .......................................... 31
Remote Wall Mounted Switch..................... 31
Electronic Pilot Ignition Wiring..................... 32
Remote Wall Mounted Switch..................... 32
Optional DC Remote System...................... 32
Canopy Installation and Glass Removal ...... 33
Brick Installation............................................. 34
Logs and Rock Wool Installation.................. 35
Operating Instructions - Millivolt ................. 38
What To Do If You Smell Gas..................... 38
Lighting Pilot for the First Time ................... 38
Lighting Pilot - Millivolt................................. 39
Lighting Burner - Millivolt............................. 40
To Turn Off Gas - Millivolt ........................... 40
Operating Instructions - Electronic Ignition 41
Lighting Electronic Ignition .......................... 41
To Turn Off Gas - Electronic Ignition........... 41
Cleaning and Maintenance ............................ 42
Burner, Pilot and Control Compartment...... 42
Burner Flame .............................................. 42
Vent System................................................ 43
Glass Door .................................................. 43
Logs ............................................................ 43
Rock Wool .................................................. 43
Replacement Parts ......................................... 44
Vent Components for 4"x65/8"..................... 44
Vent Components for 5"x8"......................... 45
Firebox Components................................... 46
Logs ............................................................ 47
Additional Accessories ............................... 48
Standing Pilot - Millivolt Control .................. 50
Electronic Ignition........................................ 52
Troubleshooting ............................................. 54
For Massachusetts Residents Only.............. 56
Warranty...........................................Back Cover
Thank you and congratulations on your purchase of a
Monessen Hearth Systems Fireplace.
PLEASE READ THE INSTALLATION AND OPERATION INSTRUCTIONS BEFORE USING THE APPLIANCE!
IMPORTANT: Read all instructions and warnings carefully before starting installation.
Failure to follow these instructions may result in a possible fire hazard and will void the warranty.

75D2523 3
4. Never install the fireplace
• in a recreational vehicle
• where curtains, furniture, clothing, or other flammable
objects are less than 42" from the front, top, or sides
of the fireplace
• in high traffic areas
• in windy or drafty areas
5. This fireplace reaches high temperatures. Keep
children and adults away from hot surfaces to
avoid burns or clothing ignition. Fireplace will
remain hot for a time after shutdown. Allow sur-
faces to cool before touching.
6. Carefully supervise young children when they
are in the room with fireplace.
7. Do not modify fireplace under any circumstances. Any
parts removed for servicing must be replaced prior to
operating fireplace.
8. Turn fireplace off and let cool before servicing, install-
ing, or repairing. Only a qualified service person should
install, service, or repair the fireplace. Have burner system
inspected annually by a qualified service person.
9. You must keep control compartments, burners, and cir-
culating air passages clean. More frequent cleaning may
be needed due to excessive lint and dust from carpeting,
bedding material, pet hair, etc. Turn off the gas valve and
pilot light before cleaning fireplace.
10. Have venting system inspected annually by a qualified
service person. If needed, have venting system cleaned
or repaired. See Cleaning and Maintenance, page 42.
11. Keep the area around your fireplace clear of combustible
materials, gasoline, and other flammable vapor and liq-
uids. Do not run fireplace where these are used or stored.
Do not place items such as clothing or decorations on or
around fireplace.
INSTALLER
Please leave these instructions with the appliance.
OWNER
Please retain these instructions for future reference .
IMPORTANT SAFETY INFORMATION
This fireplace is a vented product. This fireplace must be
properly installed by a qualified service person. The glass door
must be properly seated and sealed. If this unit is not properly
installed by a qualified service person with glass door properly
seated and sealed, combustion leakage can occur.
CARBON MONOXIDE POISONING: Early signs of
carbon monoxide poisoning are similar to the flu with head-
aches, dizziness and/or nausea. If you have these signs, the
fireplace may not have been installed properly. Get fresh
air at once! Have the fireplace inspected and serviced by a
qualified service person. Some people are more affected by
carbon monoxide than others. These include pregnant women,
people with heart or lung disease or anemia, those under the
influence of alcohol, and those at high altitudes.
Propane/LP gas and natural gas are both odorless. An odor-
making agent is added to each of these gases. The odor helps
you detect a gas leak. However, the odor added to these gases
can fade. Gas may be present even though no odor exists.
Make certain you read and understand all warnings. Keep
this manual for reference. It is your guide to safe and proper
operation of this fireplace.
1. This appliance is only for use with the type of gas indi-
cated on the rating plate. This appliance is not convertible
for use with other gases unless a certified kit is used.
2. For propane/LP fireplace, do not place propane/LP supply
tank(s) inside any structure. Locate propane/LP supply
tank(s) outdoors. To prevent performance problems, do not
use propane/LP fuel tank of less than 100 lbs. capacity.
3. If you smell gas
• shut off gas supply.
• do not try to light any appliance.
• do not touch any electrical switch; do not use any
phone in your building .
• immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions.
Continued on page 4
• Read this owner’s manual carefully and completely before trying to assemble, operate,
or service this fireplace.
• Any change to this fireplace or its controls can be dangerous.
• Improper installation or use of this fireplace can cause serious injury or death from
fire, burns, explosions, electrical shock and carbon monoxide poisoning.
WARNING

475D2523
IMPORTANT SAFETY INFORMATION
Continued from page 3
12. Do not use this fireplace to cook food or burn paper or
other objects.
13. Never place anything on top of fireplace.
14. Do not use any solid fuels (wood, coal, paper, cardboard,
etc.) in this fireplace. Use only the gas type indicated on
rating plate.
15. This appliance, when installed, must be electrically
grounded in accordance with local codes or in the
absence of local codes, with the National Electrical
Code, ANSI/NFPA 70, or the Canadian Electrical Code,
CSA C22.1.
16. Do not obstruct the flow of combustion and ventilation
air in any way. Provide adequate clearances around
air openings into the combustion chamber along with
adequate accessibility clearance for servicing and proper
operation.
17. When the appliance is installed directly on carpeting,
tile or other combustible material other than wood floor-
ing, you must set appliance on a metal or wood panel
or hearth pad extending the full width and depth of the
appliance.
18. Do not use fireplace if any part has been under or exposed
to, water. Immediately call a qualified service techni-
cian to inspect the appliance and replace any part of
the control system and any gas control which has been
submerged in water.
19. Do not operate fireplace if any log is broken.
20. Do not use a blower insert, heat exchanger insert, or
any other accessory not approved for use with this fire-
place.
21. Do not operate the fireplace with glass door removed,
cracked, or broken.
22. Massachusetts residents only see pages 56 and
57.
IMPORTANT:
PLEASE READ THE FOLLOWING CAREFULLY
It is normal for fireplaces fabricated of steel to
give off some expansion and/or contraction noises
during the start up or cool down cycle. Similar
noises are found with your furnace heat exchanger
or car engine.
IMPORTANT:
PLEASE READ THE FOLLOWING CAREFULLY
It is not unusual for gas fireplace to give off some
odor the first time it is burned. This is due to the
manufacturing process.
Please ensure that your room is well ventilated
during burn off — open all windows.
It is recommended that you burn your fireplace for
at least ten (10) hours the first time you use it. Place
the fan switch in the “OFF” position during this time.
WARNING
Never connect unit to private
(non-utility) gas wells. This gas is
commonly known as wellhead gas.
We suggest that our gas hearth
products be installed and
serviced by professionals who
are certified in the U.S. by the
National Fireplace Institute®
(NFI) as Gas Specialists.
www.nficertified.org

75D2523 5
PRODUCT FEATURES AND CODE APPROVAL
Off/Pilot/On Knob
Optional Remote
Receiver
Figure 1 - MDV500 and MDV600 Fireplace
(Millivolt Unit Shown —
Also Available in Electronic Ignition)
• This appliance has been certified for
use with either natural or propane
gas. See appropriate data plates.
• This appliance is not for use with
solid fuels.
• The appliance is approved for bed-
room or bedsitting room installa-
tions.
• The appliance must be installed in
accordance with local codes if any. If
none exist use the current installation
code. ANSI Z223.1/NFPA 54 in the
USA, CAN/CGA B149 in Canada.
• This appliance is mobile home
approved.
• The appliance must be properly con-
nected to a venting system.
• The appliance is not approved for
closet or recessed installations.
Hi/Lo Knob
PRODUCT SPECIFICATIONS
CODE APPROVAL
Direct Vent type appliances draw all combustion air from outside of the dwelling through the vent pipe.
These appliances have been tested by CSA and found to comply with the established standards for DIRECT VENT GAS
FIREPLACE HEATERS in the USA and Canada as follows:
LISTED VENTED GAS FIREPLACE HEATER
TESTED TO: ANSI Z21.88-2005/CSA 2.33-2005 STANDARDS
A manufactured home (USA only) or mobile home OEM installation must conform with the Manufactured Home Con-
struction and Safety Standard, Title 24 CFR, Part 3280, or when such a standard is not applicable, the Standard for
Manufactured Home Installations, ANSI/NCSBCS A225.1, or Standard for Gas Equipped Recreational Vehicles and
Mobile Housing, CSA Z240.4.
Blower Control
On/Off/RS Switch
Ignitor
1/2"
Nailing
Flange
5/8"
Nailing
Flange
1/2" Nailing
Flange
Hood
WARNING
Do not remove
insulation board.
Insulation
Board

675D2523
PRE-INSTALLATION INFORMATION
INSTALLING ABOVE 2000 FEET
• In the USA, the appliance must be derated 4% for every 1,000 ft above 2,000 ft elevations.
• In Canada, these appliances are certified for altitudes of 0 – 2000 ft, and must be de-rated by 10 percent for installations
between 2000 and 4,500 ft. (derate an additional 4% for every 1,000 ft. above 4,500 ft. elevations).
If the heating value of the gas has been reduced, these rules do not apply. To identify the proper orifice size, check with local
gas utility.
If installing this appliance at an elevation above 4,500 feet (in Canada), check with local authorities.
ORIFICE SIZES, PRESSURES AND BTUs
NATURAL GAS PROPANE GAS
Manifold Press: (W.C.) 3.5" Manifold Press: (W.C.) 10"
Maximum Supply Pressure 10.5" Maximum Supply Pressure 13"
Minimum Supply Pressure 4" Minimum Supply Pressure 11"
BEFORE YOU START
Read this homeowner manual thoroughly and follow all instructions carefully. Inspect all contents for shipping damage and
immediately inform your dealer if any damage is found. Do not install any unit with damaged, incomplete, or substitute parts.
Check your packing list to verify that all listed parts have been received. You should have the following:
• Fireplace (Firebox and Burner System) • Fasteners • Front Floor Brick Assembly
• White Toggle Switch • Rock Wool • Non-Combustible Panel
• Log Set • Switch Cover Plate
• Canopy • Restrictor Plate/Disc (2 each)
ITEMS REQUIRED FOR INSTALLATION
Tools: Building Supplies:
• Phillips Screwdriver • Framing Materials
• Hammer • Wall Finishing Materials
• Saw and/or saber saw • Caulking Material (Noncombustible)
• Level • Fireplace Surround Material (Noncombustible)
• Measuring Tape • Piping Complying with Local Codes
• Electric Drill and Bits • Tee Joint
• Pliers • Pipe Sealant Approved for use with Propane/LPG
• Square (Resistant to Sulfur Compounds)
• Pipe Wrench
Model Number MDV500 MDV600
Natural Propane Natural Propane
Max. Btu/hr Input 30,000 30,000 32,000 32,000
Min. Btu/hr Input 21,500 23,500 22,000 26,000
Burner Orifice size (as shipped) 7/64" #51 #34 #50

75D2523 7
B
A
H
A
E
C
D
F
G
1/2" or 5/8"
1
/2
"
or
5
/8
"
C
A
G
C
G
A1/2" or 5/8"
PRE-INSTALLATION INFORMATION
FIREPLACE FRAMING
Firebox framing can be built before or after the appliance is set in place. Construct firebox framing following Figure 2 and
the chart below for your specific installation requirements. See Figure 3 on Page 8 for firebox dimensions. The framing
headers may rest on the top of the firebox standoffs.
The firebox may be installed directly on a combustible floor or raised on a platform of an appropriate height. When the
firebox is installed directly on carpeting, tile, or other combustible material, other than wood flooring, the firebox shall be
installed on a metal or wood panel extending the full width and depth of the enclosure.
Corner Installation
Stud Location
Inside Chase Installation
Recessed Installation
Figure 2 - Framing Dimensions
WARNING
Do not fill spaces around firebox with
insulation or other materials. This
could cause a fire.
MDV500 MDV600
A42
1/16"48 1/16"
B46
1/2"46 1/2"
C32
3/4"38 3/4"
D16
3/8"19 3/8"
E73
1/2"79 1/2"
F36
3/4"39 3/4"
G20
3/8"20 3/8"
H 52" 561/4"

875D2523
F
B
149/16"
225/16"
203/4"
465/16"
Ref. to
Framing
15/16"
427/16"
Ref. to
Wall 345/8"
to
Center
of Pipe
233/16"
33/8"
403/8"
5/8"
5/8"
1/2"
1/2"
341/2"
5"
21/2"
2"
A
Ref. to Framing
C
D
E
Ref. to Wall
73/8"
121/16"
PRE-INSTALLATION INFORMATION
Figure 3 - MDV500 Fireplace Dimensions
FIREPLACE DIMENSIONS
MDV500 MDV600
A41
13/16"47 13/16"
B32
3/16"38 3/16"
C32
15/16"38 15/16"
D 36" 42"
E 41" 47"
F16
1/8"19 1/8"

75D2523 9
Y
EAB
C
D
F
Y
X
PRE-INSTALLATION INFORMATION
FIREPLACE LOCATION
Plan for the installation of your appliance. This includes determining where the unit is to be installed, the vent configuration
to be used, framing and finishing details, and whether any optional accessories (i.e. blower, wall switch, or remote control)
are desired. Consult your local building code agency to ensure compliance with local codes, including permits and inspec-
tions.
The following factors should be taken into consideration:
• Clearance to side-wall, ceiling, woodwork, and windows. Minimum clearances to combustibles must be maintained.
• This fireplace may be installed along a wall, across a corner, or use an exterior chase. See Figure 4 for suggested loca-
tions.
• Location should be out of high traffic areas and away from furniture and draperies due to heat from appliance.
• Never obstruct the front opening of the fireplace.
• Do not install in the vicinity where gasoline or other flammable liquids may be stored.
• Vent pipe routing. See Venting section found in this manual for allowable venting configurations.
• These units can be installed in a bedroom. See National Fuel Gas Code ANSI Z233.1/NFPA 54 — (current edition), the
Uniform Mechanical Code — (current edition), and Local Building Codes for specific installation requirements.
Figure 4 - Locating Gas Fireplace
** Island (C) and room divider (D) installation is possible as long as the horizontal portion of vent system (X)
does not exceed 20'. See Installing Horizontal Termination Configuration on pages 20 through 22.
* When you install your fireplace in (D) room divider or (E) flat on wall corner positions (Y), a minimum of 6"
clearance must be maintained from perpendicular wall and front of fireplace.
A Flat on Wall
B Cross Corner
C Island**
D Room Divider*
E Flat on Wall Corner*
F Chase Installation
Y 6" Minimum

10 75D2523
The fireplace must be secured to the floor and/or to framing studs as shown in Figure 5 . Use two (2) wood screws or masonry/
concrete screws to secure fireplace to the floor. Use four (4) screws to attach fireplace to framing. The side brackets or nail-
ing flanges are designed to accommodate two thickness of wall boards (1/2" or 5/8").
SECURING FIREPLACE TO FLOOR OR FRAMING
Figure 5 - Securing Fireplace to Floor and Framing Studs
Framing
Framing
Screws
Screws
Screws
Screws
Screws
Nail Flange
Nail Flange