Monessen Hearth ARTISAN Series User manual

1
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Installation Manual
Installation and Appliance Setup
INSTALLER: Leave this manual with party responsible for use and operation.
OWNER: Retain this manual for future reference.
NOTICE: DO NOT discard this manual!
In the Commonwealth of Massachusetts
installation must be performed by a licensed
plumber or gas tter.
See Table of Contents for location of
additional Commonwealth of Massachusetts
requirements.
• DO NOT store or use gasoline or other am-
mable 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.
- Leave the building immediately.
- Immediately call your gas supplier from
a neighbor’s phone. Follow the gas sup-
plier’s instructions.
- If you cannot reach your gas supplier, call
the re department.
• Installation and service must be performed
by a qualied installer, service agency, or the
gas supplier.
WARNING:
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly
could result in serious injury, death, or
property damage.
ARTISAN
SERIES
This is an unvented gas-red heater. It uses air
(oxygen) from the room in which it is installed.
Provisions for adequate combustion and
ventilation air must be provided. Refer to Page 6.
DO NOT install this appliance in a bedroom or
bathroom. Please refer to page 6 Section F for
proper appliance placement.
Models:
AVFL42NIP-BU/PIP-BU
AVFL42NIP-RB/PIP-RB
AVFL48NIP/PIP
AVFLST48NIP/PIP
AVFL60NIP-B/PIP-B
This appliance may be installed in an after-mar-
ket, permanently located, manufactured (mobile)
home, where not prohibited by local codes.
This appliance is only for use with the type of
gas indicated on the rating plate. This appli-
ance is not convertible for use with other
gases.

2Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Safety Alert Key:
• DANGER! Indicates a hazardous situation which, if not avoided will result in death or serious injury.
• WARNING! Indicates a hazardous situation which, if not avoided could result in death or serious injury.
• CAUTION! Indicates a hazardous situation which, if not avoided, could result in minor or moderate injury.
• NOTICE: Used to address practices not related to personal injury.
Table of Contents
Installation Standard Work Checklist ....................3
1 Product Specic and Important Safety Information
A. Appliance Certication ............................4
B. BTU Specications ...............................4
C. High Altitude Installations ..........................4
D. Non-Combustible Materials Specication. . . . . . . . . . . . . . 4
E. Combustible Materials Specication .................4
F. Electrical Codes .................................4
2 Getting Started
A. Design and Installation Considerations ...............5
B. Tools and Supplies Needed ........................5
C. Inspect Appliance and Components ..................5
D. Getting Started ..................................6
E. Planning the Installation ...........................6
F. Adequate Combustion Ventilation Air .................6
G. Important Safety and Operating Information ...........8
3 Framing and Clearances
A. Appliance & Framing Dimension Diagrams ...........10
B. Clearances and Height Requirements ...............14
C. Good Faith Wall Surface TV Guidelines .............. 16
D. Constructing the Appliance Chase ..................18
E. Floor Protection ................................18
4 Appliance Preparation
A. Securing and Leveling the Appliance ................19
B. Installing Non-Combustible Facing Material ..........20
5 Gas Information
A. Fuel Type .....................................21
B. Gas Pressure ..................................21
C. Gas Service Access .............................21
D. Connect to Gas ................................23
E. Valve Access ..................................24
F. Check Gas Pressure ............................24
G. Gas Connection ................................25
H. High Altitude Installations .........................25
6 Electrical Information
A. General Information .............................26
B. Wiring Requirements ............................27
7 Final Installation
A. Black Magic Glass Installation .....................29
B. Installation of Air Deection Glass ..................30
C. Crushed Glass Media Only Placement .............. 30
D. Glass and Optional Stone Kit Placement .............30
E. Placement of Optional Logs .......................32
F. Lighting Instructions (IPI) .........................35
8 Finishing
A. Facing and Finishing Instructions ...................36
B. Operation During a Power Outage ..................38
C. Detailed Component Operating Instructions.—Intellire Plus
ODS .........................................39
D. Troubleshooting ................................41
E. Accessories ...................................43
WARNING! RISK OF FIRE OR EXPLOSION AND ASPHYXIATION HAZARD
Improper adjustment, alteration, service, maintenance, or installation of this heater
or its controls can cause death or serious injury.
Read and follow instructions and precautions in User’s Information Manual
provided with this heater.

3
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Installation Standard Work Checklist
Customer:
Lot/Address:
Model (circle one): AVFL42NIP-BU/PIP-BU, AVFL42NIP-RB/PIP-RB
AVFL48NIP/PIP, AVFLST48NIP/PIP, AVFL60NIP-B/PIP-B
Date Installed:
Location of Appliance:
Installer:
Dealer/Distributor Phone #
Serial #:
Comments: Further description of the issues, who is responsible (Installer/ Builder/ Other Trades, etc) and corrective
action needed _____________________________________________________________________________________
Comments Communicated to party responsible ____________________ by ______________________on ___________
(Builder / Gen. Contractor/) (Installer) (Date)
?YHW , ON F I SEY
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
___________________________
4099-982A 02/21
= Contains updated information.
• Photographing the installation and copying this checklist for your file.
• That this checklist remain visible at all times on the appliance until the installation is complete.
This standard work checklist is to be used by the installer in conjunction with, not instead of, the instructions contained in this
installation manual.
WARNING! Risk of Fire or Explosion! Failure to install appliance according to these instructions could
lead to a fire or explosion.
ATTENTION INSTALLER:
Follow this Standard Work Checklist
Appliance Install Sections 2 and 4
Verified that the chase is insulated and sealed.
Required non-combustible board is installed.
Verifi ed clearances to combustibles.
Fireplace is level ed and secured.
Adequate provisions for combustion and ventilation air have been verified.
Gas Section 5
Proper appliance for fuel type.
Leak check performed and inlet pressure verified.
Verified proper air shutter setting for installation type.
Electrical Section 6
Unswitched power (110-120 VAC) provided to the appliance.
Switch wires properly installed.
Crushed Glass Media & Logs Section 7
All packaging and protective materials removed (inside & outside of appliance).
Crushed glass media installed correctly.
Accessories installed properly.
Finishing Section 8 (Pg 27)
Verifi ed all clearances meet installation manual requirements.
Mantels and wall projections comply with installation manual requirements.
Manual bag and all of its contents are removed from inside/
under the appliance and given to party responsible for use and operation.
Started appliance and veried no gas leaks exist.
Hearth & Home Technologies recommends the following:

4Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
This product is listed to ANSI standards for "Unvented
Room Heaters” and applicable sections of "Gas Burning
Heating Appliances for Manufactured Homes" and "Gas
Fired Appliances for Use at High Altitude."
A. Appliance Certication
D. Non-Combustible Materials Specication
Material which will not ignite and burn. Such materials are
those consisting entirely of steel, iron, brick, tile, concrete,
slate, glass or plasters, or any combination thereof.
Materials that are reported as passing ASTM E 136,
Standard Test Method for Behavior of Materials in
a Vertical Tube Furnace at 750 ºC shall be considered
non-combustible materials.
E. Combustible Materials Specication
Materials made of or surfaced with wood, compressed pa-
per, plant bers, plastics, or other material that can ignite
and burn, whether ame proofed or not, or plastered or
unplastered shall be considered combustible materials.
F. Electrical Codes
NOTICE: This appliance must be electrically wired
and grounded in accordance with local codes or, in the
absence of local codes, with National Electric Code
ANSI/NFPA 70-latest edition or the Canadian Electric
Code CSA C22.1.
• A 110-120 VAC circuit for this product must be pro-
tected with ground-fault circuit-interrupter protection,
in compliance with the applicable electrical codes,
when it is installed in locations such as in bathrooms
or near sinks.
NOT INTENDED FOR USE AS A PRIMARY HEAT SOURCE.
This appliance is tested and approved as either supplemen-
tal room heat or as a decorative appliance. It should not be
factored as primary heat in residential heating calculations.
NOTICE: This installation must conform with local codes.
In the absence of local codes you must comply with the
National Fuel Gas Code, ANSI Z223.1-latest edition in
the U.S.A.
1 Product Specic and Important Safety Information
B. BTU Specications
C. High Altitude Installations
NOTICE: If the heating value of the gas has been reduced,
these rules do not apply. Check with your local gas utility
or authorities having jurisdiction.
When installing above 2000 feet elevation: Reduce input
rate 4% for each 1000 feet above 2000 feet.
Check with your local gas utility to determine proper
orice size.
GAS PRESSURES
NOTE: For LP models an external regulator is required
to reduce supply pressure to a maximum of 13" w.c.
NATURAL PROPANE (LP)
Inlet Minimum 5.0" w.c. 11.0" w.c.
Inlet Maximum 10.0" w.c. 13.0" w.c.
Regulator Pressure
Setting
3.5" w.c. 10" w.c.
Pilot Regulator 3.5" w.c. —
WARNING: This product and the
fuels used to operate this product (liquid
propane or natural gas), and the products
of combustion of such fuels, can expose
you to chemicals including benzene, which
is known to the State of California to cause
cancer and reproductive harm. For more
information go to: www.P65Warnings.
ca.gov.
MODEL: AVFL42NIP-BU, AVFL42PIP-BU, AVFL42NIP-RB,
AVFL42PIP-RB, AVFL48NIP, AVFL48PIP, AVFLST48NIP,
AVFLST48PIP, AVFL60NIP-B, AVFL60PIP-B
LABORATORY: UNDERWRITERS LABORATORIES, INC.
(UL)
TYPE: Unvented Room Heaters
STANDARD: ANSI Z21.11.2:19
Models Maximum
Input
BTU/h
Minimum
Input BTU/h
Orice
Size (DMS)
AVFL42NIP-BU (NG) (0-2000 FT) 34,000 23,500 .1110(#34)
AVFL42PIP-BU (PROPANE) (0-2000 FT) 33,000 26,000 .070(#50)
AVFL42NIP-RB (NG) (0-2000 FT) 24,500 17,500 .096(#41)
AVFL42PIP-RB (PROPANE) (0-2000 FT) 24,000 19,000 .0595(#53)
AVFL48NIP (NG) (0-2000 FT) 39,000 27,500 .120(#31)
AVFL48PIP (PROPANE) (0-2000 FT) 38,000 31,000 .076(#48)
AVFLST48NIP (NG) (0-2000 FT) 39,000 27,500 .120(#31)
AVFLST48PIP (PROPANE) (0-2000 FT) 38,000 31,000 .076(#48)
AVFL60NIP-B (NG) (0-2000 FT) 40,000 28,000 .120(#31)
AVFL60PIP-B (PROPANE) (0-2000 FT) 39,000 30,500 .076(#48)

5
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
2 Getting Started
A. Design and Installation Considerations
Installation MUST comply with local, regional, state and
national codes and regulations. Consult insurance carrier,
local building inspector, re o󰀩cials or authorities having
jurisdiction over restrictions, installation inspection and
permits.
Before installing, determine the following:
• Where the appliance is to be installed.
• Gas supply piping.
• Electrical wiring requirements.
• Framing and nishing details.
• Whether optional accessories—devices such as a wall
switch or remote control—are desired.
Improper installation, adjustment, alteration, service or
maintenance can cause injury or property damage. For
assistance or additional information, consult a qualied
service technician, service agency or your dealer.
Installation and service of this appliance should
be performed by qualied personnel. Hearth
& Home Technologies recommends HHT
Factory Trained or NFI certied professionals.
C. Inspect Appliance and Components
• Carefully remove the appliance and components from
the packaging.
• The accessories and fronts may be shipped in separate
packages.
• Crushed Glass Media may be packaged separately.
• Report to your dealer any parts damaged in shipment,
particularly the condition of the glass.
•Read all of the instructions before starting the instal-
lation. Follow these instructions carefully during the
installation to ensure maximum safety and benet.
WARNING! Risk of Fire or Explosion! Damaged parts
could impair safe operation. DO NOT install damaged, in-
complete or substitute components. Keep appliance dry.
B. Tools and Supplies Needed
Before beginning the installation be sure that the following
tools and building supplies are available.
• Tape measure
• Pliers
• Hammer
• Gloves
• Voltmeter
• Level
• Manometer
• Framing material
• Phillips screwdriver
• Framing square
• Plumb line
• Safety glasses
• Reciprocating saw
• Flat blade screwdriver
• 1/2 - 3/4 in. length, #6 or #8 Self-drilling screws
• Non-corrosive leak check solution
• Electric drill and bits (1/4 in. magnetic)
• External regulator (for propane/LPG only)
• Piping which complies with local codes
• Pipe sealant approved for use with propane/LPG
(Resistant to sulfur compounds)
Hearth & Home Technologies disclaims any responsibility
for, and the warranty will be voided by, the following actions:
• Installation and use of any damaged appliance.
• Modication of the appliance.
• Installation other than as instructed by Hearth & Home
Technologies.
• Installation and/or use of any component part not approved
by Hearth & Home Technologies.
Any such action may cause a re hazard.
WARNING! Risk of Fire, Explosion or Electric Shock!
DO NOT use this appliance if any part has been under
water. Call a qualied service technician to inspect the
appliance and to replace any part of the control system
and/or gas control which has been under water.
• Manual shuto󰀨 valve
• Sediment trap
• Tee joint
• Pipe wrench
WARNING
This appliance is equipped for (natural or propane)
gas. Field conversion is not permitted.

6Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
D. Getting Started
Verify that all listed parts have been received. You should
have the following:
• Unvented gas heater
• Two (2) anchoring screws
• Installation and Owner’s instructions
• 7.25" non-combustible board
• Deector glass
• Five (5) bags crushed glass media (60" appliances)
• Four (4) bags crushed glass media (42" and 48"
appliances)
• RC300 remote control
Carefully inspect the contents for shipping damage. If any
parts are missing or damaged, immediately inform the
dealer from whom you purchased the appliance. Do not
attempt to install any part of the appliance unless you
have all parts in good condition.
F. Adequate Combustion Ventilation Air
This heater shall not be installed in a conned space or
unusually tight construction unless provisions are provided
for adequate combustion and ventilation air.
The National Fuel Gas Code, (ANSI Z223.1/NFPA54),
denes a conned space as a space whose volume is less
than 50 cubic feet per 1,000 BTU per hour (4.8m3per kw)
of the aggregate input rating of all appliances installed in
that space, and an unconned space as a space whose
volume is not less than 50 cubic feet per 1,000 BTU per
hour (4.8 m3per kw) of the aggregate input rating of all
appliances installed in that space. Rooms communicating
directly with the space in which the appliances are installed,
through openings not furnished with doors, are considered
a part of a conned space.
Unusually tight construction is dened as construction
where:
a. Walls and ceilings exposed to the outside atmosphere
have a continuous water vapor retarder with a rating of
1 perm (6 x 1011 kg per pa/sec-m2) or less with openings
gasketed or sealed, and
b. Weather stripping has been added to windows and
doors, and
c. Caulking or sealants are applied to areas such as joints
around window and door frames, between sole plates
and oors, between wall-ceiling joints, between wall
panels, at penetrations for plumbing, electrical and gas
lines and other openings.
The following formula can be used to determine the maxi-
mum heater rating per the denition of unconned space:
BTU/Hr = (L1+ L2) Ft x (W) Ft x (H) Ft
50
Consider two connecting rooms with an open area
between, with the following dimensions:
L1 = 151/2 Ft., L2 = 12 Ft., W = 12 Ft., H = 8 Ft.
BTU/Hr = (151/2 + 12) x (12) x (8)
50
If there were a door between the two rooms the calculation
would be based only on the room with the heater.
BTU/Hr = (151/2) x (12) x (8)
50
Do not install the heater:
•Where curtains, furniture, clothing, or
other ammable objects are less than
36" from the front of the heater.
• In high tra󰀩c areas.
•In windy or drafty areas.
E. Planning the Installation
When planning the installation of the appliance it is neces-
sary to determine where the appliance is to be installed
and whether optional accessories are desired. Gas supply
piping should also be planned. The following steps repre-
sent the normal sequence of installation. Each installation
is unique, however, and might require a di󰀨erent sequence.
1. Position appliance in desired location. Refer to the Appli-
ance Location (page 7, Figure 2.2) and Clearances and
Height Requirements (page 12, Figures 3.6 and 3.7)
sections and Appliance and Framing Dimensions (page
10 and 11, Figure 3.4 and 3.5) illustration found in this
manual.
NOTE: Be sure all packing material has been removed
from under and behind the unit.
2. Install following the instructions found in this manual.
3. Field wire main power supply to junction box. Refer to the
Electrical Installation section (page 23). (Electrical con-
nections should only be performed by an experienced,
licensed certied service person).
4. Plumb gas line. Gas line may be run either through
bottom of unit or left side. There is no right side access.
Refer to the Connect the Gas (page 20, Figure 5.3)
section found in this manual. (Gas connections should
only be performed by an experienced, licensed/certied
service person).
5. Complete nish wall material and/or surround.
WARNING
WARNING
Gloves are recommended when handling
ceramic ber logs to prevent skin irritation
from loose bers. Logs are fragile—handle
with care.

7
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
W
H
Counter Appliance
If the area in which the heater may be
operated does not meet the required volume
for indoor combustion air, combustion and
ventilation air shall be provided by one
of the methods described in the National
Fuel Gas Code, ANSI Z223.1/NFPA 54, the
International Fuel Gas Code or applicable
local codes.
Figure 2.1
APPLIANCE LOCATION
This unvented gas heater requires no outside venting and
burns cleanly and e󰀩ciency. As a zero-clearance unvented
gas heater, it can be installed against (or recessed into)
any wall that is accessible to a gas line.
Carefully select the best location for installation of your
unvented appliance. The following factors should be taken
into consideration.
•Clearance to side wall, ceiling, woodwork and window
or other combustibles. Refer to Clearance and Height
Requirements section on Page 12. Minimum clear-
ances to combustibles must be maintained.
• Location must not be a󰀨ected by drafts caused by
kitchen exhaust fans, ceiling fans, return air registers
for forced air furnaces / air conditioners, windows or
doors.
• Installation must provide adequate ventilation and
combustion air.
• DO NOT INSTALL THIS MODEL IN A BEDROOM
OR BATHROOM.
• Location should be out of high tra󰀩c areas and
away from furniture and draperies due to heat from
rebox.
FP3029
replace locations
Figure 2.2
• Never obstruct the front opening of the unvented appli-
ance or restrict the ow of combustion and ventilation
air.
• Minimize modications to existing construction. Refer
to Figure 2.2 below for location suggestions.
• Do not install in the vicinity where gasoline or other
ammable liquids may be stored. The unvented re-
box must be kept clear and free from the combustible
materials.
NOTICE: Illustrations reect typical installations and are
FOR DESIGN PURPOSES ONLY. Illustrations/diagrams
are not drawn to scale. Actual installation could vary due
to individual design preference.
It is important to follow the framing and nishing instruc-
tions step by step to ensure proper placement of appli-
ance in the surrounding framing/nishing materials.
WARNING
Appliance

8Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
•Any change to this appliance or its controls can be dangerous.
• Improper installation or use of the appliance can cause serious injury or death from re, burns,
explosion or carbon monoxide poisoning.
• Do not allow fans to blow directly into the appliance. Avoid any drafts that alter burner ame patterns.
•Do not use a blower insert, heat exchanger insert or other accessory, not approved for use with
this heater where applicable.
1. Due to high temperatures, the appliance should be
located out of tra󰀩c and away from furniture and
draperies.
2. Children and adults should be alerted to the hazard
of high surface temperature and should stay away
to avoid burns or clothing ignition.
3. Young children should be carefully supervised when
they are in the same room with the appliance.
4. Do not place clothing or other ammable material
on or near the appliance.
5. Any safety screen or guard removed for servicing
an appliance, must be replaced prior to operating
the heater.
6. Installation and repair should be done by a qualied
service person. The appliance should be inspected
before use and at least annually by a professional
service person. More frequent cleaning may be
required due to excessive lint from carpeting,
bedding material, etc. It is imperative that control
compartments, burners, and circulating air pas-
sageways of the appliance be kept clean.
7. This appliance is intended for supplemental heating.
8. CARBON MONOXIDE POISONING: Early signs of
carbon monoxide poisoning are similar to the u with
headaches, dizziness and/or nausea. If you have these
signs, obtain fresh air immediately. Have the heater
serviced as it may not be operating properly.
9. The installation must conform with local codes or, in
the absence of local codes, with the National Fuel
Gas Code, ANSI Z223.l/NFPA54.
10. Do not install this appliance in a bathroom or bedroom.
11. Correct installation of the crushed glass media, optional
stone and ceramic ber logs, proper location of the
appliance, and annual cleaning are necessary to avoid
potential problems with sooting. Sooting, resulting
from improper installation or operation, can settle on
surfaces outside the appliance. Refer to log placement
instructions for proper installation.
12. WARNING: Do not allow fans to blow directly into the
appliance. Avoid any drafts that alter burner ame
patterns. Do not place a blower inside burn area of
appliance. Ceiling fans may create drafts that alter
burner ame patterns. Sooting and improper burning
will occur.
13. Caution: Candles, incense, oil lamps, etc. produce
combustion by-products including soot. Vent-free
appliances will not lter or clean soot produced by
these types of products. In addition, the smoke and/
or aromatics (scents) may be reburned in the vent-free
appliance which can produce odors. It is recommended
to minimize the use of candles, incense, etc. while the
vent-free appliance is in operation.
14. This heater shall not be installed in a room or space
unless the required volume of indoor combustion air is
provided by the method described in the National Fuel
Gas Code, ANSI Z223.1/NFPA 54, the International
Fuel Gas Code or applicable local codes.
15. Keep room area clear and free from combustible mate-
rials, gasoline and other ammable vapors and liquids.
16. Unvented appliances emit moisture into the living
area. In most homes of average construction, this
does not pose a problem. In houses of extremely
tight construction, additional mechanical ventilation is
recommended.
17. During manufacturing, fabricating and shipping, various
components of this appliance are treated with certain
oils, lms or bonding agents. These chemicals are not
harmful but may produce annoying smoke and smells
as they are burned o󰀨 during the initial operation of the
appliance; possibly causing headaches or eye or lung
irritation. This is a normal and temporary occurrence.
The initial break-in operation should last three to four
hours with the burner at the highest setting. Provide
maximum ventilation by opening windows or doors to
allow odors to dissipate. Any odors remaining after this
initial break-in period will be slight and will disappear
with continued use.
18. Input ratings are shown in BTU per hour and are for
elevations up to 2,000 feet. For elevations above 2,000
feet, input ratings should be reduced 4 percent for each
1,000 feet above sea level. Refer to the National Fuel
Gas Code.
G. Important Safety and Operating Information
WARNING

9
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Figure 3.2 General Operating Parts
General Operating Parts
C. Fuel Specications
WARNING! Risk of Fire or Explosion! Appliance must
be set up for compatible gas type!
• This appliance is designed to operate on either natural
gas or propane. Make sure the appliance is compatible
with gas type selected for installation site.
Figure 3.2 references the general operating parts of the
appliance and the section of this manual in which they are
discussed.
CLEAR SPACE
SECTION 3.A.
DECORATIVE DOORS
SECTION 4
GLASS ASSEMBLY
SECTION 4
OPERATION DURING
A POWER OUTAGE
SECTION 3.I
WARNING! Risk of Fire! Comply with all minimum
clearances to combustibles as specied in the installation
instructions.
19. The appliance and its appliance main gas valve must
be disconnected from the gas supply piping system
during any pressure testing of that system at test pres-
sures in excess of 1⁄2 psig (3.5 kPa).
20. The appliance must be isolated from gas supply piping
system by closing its equipment shuto󰀨 valve during
any pressure testing of the gas supply piping system at
test pressures equal to or less than 1⁄2 psig (3.5 kPa).
21. Do not use this room heater if any part has been under
water. Immediately call a qualied service technician
to inspect the room heater and to replace any part of
the control system and any gas control which has been
under water.
22. Never burn solid fuels in a appliance where a unvented
room heater is installed.
23. WARNING: Failure to keep the primary air opening
of the burner clean may result in sooting and property
damage.
24. WARNING: Do not use a blower insert, heat exchanger
insert or other accessory not approved for use with this
heater.
BUILDING CODE INFORMATION
Adhere to all local codes or, in their absence, the latest
edition of THE NATIONAL FUEL GAS CODE ANSI Z223.1
or NFPA54 which can be obtained from:
American National Standards Institute, Inc.
1430 Broadway
New York, NY 10018
or
National Fire Protection Association, Inc.
Batterymarch Park
Quincy, MA 02269

10 Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
3 Framing and Clearances
Figure 3.1 - Appliance Dimensions
A. Appliance and Framing Dimensions
13-3/8 in
3 in 3-1/8 in
6-1/2 in
9-1/8 in
7-1/4 in
8 in
17 in
8-1/8 in
A
B
C
40-1/4 in
33 in
3-3/4 in
3-1/8 in
5-3/8 in
39-1/2 in
AVFL42 AVFL48 AVFL60
A 42 in 48 in 60 in
B 45-1/4 in 51-1/4 in 63-1/4 in
C46-1/8 in 52-1/8 in 64-1/8 in

11
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Figure 3.2 - AVFLST48 Appliance Dimensions
Figure 3.3 - AVFLST48 With Outdoor Kit Appliance Dimensions
7-1/4 in
8 in
17 in
8-1/8 in
40-1/4 in
33 in
3-3/4 in
3-1/8 in
5-3/8 in
39-1/2 in
48 in
51-1/4 in
52-1/8 in
13 in
3-1/8 in 3-1/8 in
6-1/2 in
8-7/8 in
14-7/8 in
3-3/4 in
3-1/8 in
5-3/8 in
39-1/8 in
55-1/2 in
52-1/8 in
21-1/8 in
6-1/8 in
6 in
5-7/8 in
33-1/4 in
3-1/8 in
6 in
8-3/8 in
39-1/2 in

12 Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Figure 3.4 - Framing Dimensions
C
1/2”
1/2”
C
D
13-1/8”
39-3/4”
Framing
A
B
AVFL42 AVFL48 AVFL60
A 42 in 48 in 60 in
B46-5/8 in 52-5/8 in 64-5/8 in
C 47-7/8 in 55-3/8 in 63-7/8 in
D 71-1/4 in 78-1/4 in 90-3/8 in

13
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
39-3/4”
Framing
48”
52-5/8”
52-5/8”
1/2”
1/2” 55-7/8”
13-1/2”
1/2”
52-5/8”
11-5/8”
Figure 3.5 - AVFL48ST Framing Dimensions
Exterior Wall Installation
Interior Wall Installation

14 Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
B. Clearances and Height Requirements
Ensure that minimum clearances shown in Figures 3.6, 3.7,
3.8 and 3.9 are maintained. Left and right clearances are
determined when facing the front of the appliance.
Follow these instructions carefully to ensure safe instal-
lation. Failure to follow these requirements may create a
re hazard.
Sidewall and Mantel Clearances — The clearance from
the inside of the appliance to any combustible adjacent
wall should not be less than 6". Mantel leg clearances are
projected out at a 45° angle. Figure 3.6, 3.7, 3.8 and 3.9 .
Ceiling Clearance — The ceiling must be at least 36"
from the appliance opening. Figure 3.6, 3.7, 3.8 and 3.9.
Back Wall Clearance — The appliance may be placed
against a combustible back wall.
The dimensions shown in Figures 3.6, 3.7,
3.8 and 3.9 are minimum clearances to
maintain when installing this appliance. Left
and right clearances are determined when
facing the front of the heater.
Follow these instructions carefully to
ensure safe installation. Failure to follow
instructions exactly can create a re hazard.
Floor Clearance — The appliance may be installed directly
on a combustible oor or a raised platform of an appropriate
height. Do not place appliance on carpeting, vinyl, tile or
other soft oor coverings. It may, however, be placed on at
wood, plywood, particle board or other hard surfaces. Be
sure appliance rests on a solid continuous oor or platform
with appropriate framing for support so that no cold air can
enter from under the rebox.
Mantel clearances — Must meet the clearance require-
ments detailed in Figures 3.6, 3.7, 3.8 and 3.9 .
Figure 3.6 - Combustible Mantel Clearances
(AVFL42N(P)IP-BU, AVFL48N(P)IP, AVFL60N(P)IP-B, AND
AVFLST48N(P)IP appliances)
Figure 3.7 - Combustible Mantel Clearances
(AVFL42N(P)IP-RB)
Ceiling
Wall
Stud
Non-Combustible
Board
Stando
36
Top of Appliance
Opening
22
8
20
3
17-1/2
19
6
SIDE VIEW
Sidewall
Appliance
Opening
TOP VIEW
WARNING
See Good Faith Guidelines for TV Installations on
pages 14 & 15, Figure 3.10 & 3.11.
Ceiling
Wall
Stud
Non-Combustible
Board
Stando
36
Top of Appliance
Opening
18
14
15-1/2
8
SIDE VIEW
TOP VIEW Sidewall
Appliance
Opening

15
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
SIDE VIEW
TOP VIEW
Ceiling
Wall
Stud
Non-Combustible
Board
Stando
36
Top of Appliance
Opening
20
8
19
3
17-1/2
19
6
Figure 3.8 - Non-Combustible Mantel Clearances
(AVFL42N(P)IP-BU, AVFL48N(P)IP, AVFL60N(P)IP-B, AND
AVFLST48N(P)IP appliances)
Figure 3.9 - Non-Combustible Mantel Clearances
(AVFL42N(P)IP-RB)
SIDE VIEW
TOP VIEW
Ceiling
Wall
Stud
Insulation
Board
36
Top of Appliance
Opening
16
13-1/2
8
12
12
6
7"
Appliance
Opening
Sidewall
7"
Appliance
Opening
Sidewall
Note: Reducing clearances further requires non-com-
bustible construction materials (eg: steel studs, du-
rock, etc) to a height of 12 inches above the framing
height.
Note: Reducing clearances further requires non-com-
bustible construction materials (eg: steel studs, du-
rock, etc) to a height of 12 inches above the framing
height.

16 Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Figure 3.10 - Good Faith TV Guidelines
C. Good Faith Wall Surface TV Guidelines
(AVFL42N(P)IP-BU, AVFL48N(P)IP, AVFL60N(P)IP-B, AND AVFLST48N(P)IP appliances)
Combusble Mantel
A
inch
22.00
Non-Combusble Mantel
inch 20.00
Good Faith Guidelines for TV on’s above a Typical Gas Fireplace
TV on the wall TV recessed into the wall
Notes:
1. These are good faith recommended clearances only and not a guarantee of compliance with all TV
manufacturers’ maximum allowable operating temperatures.
2. Since every home has unique air ow characteristics and maximum allowable operating temperatures can
vary from manufacturer to manufacturer and from model to model, actual TV temperatures should be
validated at the time of each installation. TVs should not be used in situations where the actual TV
temperature exceeds the manufacturers’ maximum allowable operating temperatures identied in the
TV’s technical specications. Contact the TV’s manufacturer directly if you cannot locate this information
or have questions regarding the information.
3. Mantel height and depth must conform to mantel requirements specied in the replace installation
manual.
4. “A” dimension taken from the top of the rebox opening.
5. Suggestions on how to further reduce TV temperatures:
-Increase “A” and/or 28” minimum TV height dimensions.
6" Min.
A Min.
28" Min.
12" Min.
TV
28" Min.
A Min.
12" Min.
TV
Top of appliance
opening
Top of appliance
opening

17
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Good Faith Wall Surface TV Guidelines (continued)
(AVFL42N(P)IP-RB)
Combusble Mantel
A
inch
14.00
Non-Combusble Mantel
inch
12.00
Good Faith Guidelines for TV on’s above a Typical Gas Fireplace
TV on the wall TV recessed into the wall
Notes:
1. These are good faith recommended clearances only and not a guarantee of compliance with all TV
manufacturers’ maximum allowable operating temperatures.
2. Since every home has unique air ow characteristics and maximum allowable operating temperatures can
vary from manufacturer to manufacturer and from model to model, actual TV temperatures should be
validated at the time of each installation. TVs should not be used in situations where the actual TV
temperature exceeds the manufacturers’ maximum allowable operating temperatures identied in the
TV’s technical specications. Contact the TV’s manufacturer directly if you cannot locate this information
or have questions regarding the information.
3. Mantel height and depth must conform to mantel requirements specied in the replace installation
manual.
4. “A” dimension taken from the top of the rebox opening.
5. Suggestions on how to further reduce TV temperatures:
-Increase “A” and/or 18” minimum TV height dimensions.
6" Min.
A Min.
" Min.
" Min.
TV
8" Min.
A Min.
" Min.
TV
Top of appliance
opening
Top of appliance
opening
Figure 3.11 - Good Faith TV Guidelines

18 Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
E. Floor Protection
NOTICE: Install appliance on hard metal or wood surfaces
extending full width and depth. DO NOT install directly
on carpeting, vinyl, tile or any combustible material other
than wood.
WARNING! Risk of Fire! Maintain specied air space
clearances to appliance and vent pipe:
• Insulation and other materials must be secured to prevent
accidental contact.
• The chase must be properly blocked to prevent blown
insulation or other combustibles from entering and
making contact with appliance or chimney.
• Failure to maintain airspace could cause overheating
and re.
Figure 3.12 - Floor Protection
D. Constructing the Appliance Chase
A chase is a vertical box-like structure built to enclose the
gas appliance.
NOTICE: Construction of the chase may vary with the type
of building. These instructions are not substitutes for the
requirements of local building codes. Therefore, you MUST
check local building codes to determine the requirements
to these steps.
Chases should be constructed in the manner of all out-
side walls of the home to prevent cold air drafting prob-
lems. The chase should not break the outside building
envelope in any manner.
Walls, ceiling, base plate and cantilever oor of the chase
should be insulated. Vapor and air inltration barriers
should be installed in the chase as per regional codes for
the rest of the home. Additionally, in regions where cold
air inltration may be an issue, the inside surfaces may be
sheet rocked and taped (or an equivalent method may be
used) to achieve maximum air tightness.
To further prevent drafts, the wall shield and ceiling re-
stops should be sealed with caulk with a minimum of
300ºF continuous exposure rating to seal gaps. Gas line
holes and other openings should be sealed with caulk
with a minimum of 300ºF continuous exposure rating or
stu󰀨ed with unfaced insulation. If the appliance is being
installed on a cement surface, a layer of plywood may be
placed underneath to prevent conducting cold up into the
room.
Note: Figure 3.10, 3.11, and 3.12 show the appliance installed
on the oor. However, this appliance can be elevated o󰀨 the
oor provided that the appliance is properly supported by
framing materials and the ceiling clearances are maintained.

19
Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
4 Appliance Preparation
A. Securing and Leveling the Appliance
WARNING! Risk of Fire! Prevent contact with:
• Sagging or loose insulation
• Insulation backing or plastic
• Framing and other combustible materials
Block openings into the chase to prevent entry of blown-
in insulation. Make sure insulation and other materials
are secured.
DO NOT notch the framing around the appliance
standos. Failure to maintain air space clearance could
cause overheating and re.
To properly position, level, and secure the appliance, see
below. Nailing tabs are provided to secure the appliance
to the framing members.
• Bend out the two nailing tabs on each side.
• Place the appliance into position.
• Keep nailing tabs ush with the framing. See Figure 4.2.
• Level the appliance from side to side and front to back.
• Shim the appliance as necessary. It is acceptable to use
wood shims underneath the appliance.
• Secure the appliance to the framing by using nails or
screws through the nailing tabs.
Figure 4.2 - Securing Appliance to Framing
Nailing Flange
Non-Combustible
Board
Framing Members
7-1/4 in.
Nailing Flange
Nailing Flange
Screws
Screws
Figure 4.1 - Non-Combustible Board Installation
51-1/4”
7-1/4”
51-1/4”
Standos
39-3/8”
Some gures in manual show the appliance installed on
the oor. However, this appliance can be elevated o󰀨 the
oor provided that the appliance is properly supported
by framing materials and the ceiling clearances are
maintained.

20 Monessen • AVFL Series Installation Manual • 4099-901 Rev. A • 03/21
Setting the Appliance into the Framing
The left and right nailing tabs were designed as a means
to ensure the appliance is mounted ush with the framing
materials. See Figures 4.2 and 4.3.
1. Bend out all nailing tabs. The AVFL60 has four nailing
tabs, two on each side in the middle of the appliance.
2. Screw each nailing tab to the adjoining framing ma-
terial. See Figures 3.1-3.7 for framing and clearance
details.
Figure 4.3 - Nailing Tabs
Figure 4.4 - Install Non-Combustible Facing Material
B. Installing Non-Combustible Facing Material
WARNING! Risk of Fire!
• Follow these instructions exactly.
• Facing materials must be installed properly to prevent
re.
• No materials may be substituted without authorization
by Hearth & Home Technologies.
• Non-combustible facing material needs to be at least
7-1/4" high and the full width of the appliance.
• Attach non-combustible facing material to the framing
members with regular sheetrock screws.
• Use a wet or dry towel or soft brush to remove dust or
dirt from facing material.
• See Section 8 for nishing materials guidelines.