Monessen Hearth BFC36 User manual

647
BFC cover
8/18/00 djt
BFC
Balanced Flue
(Closed Combustion)
Heat-Circulating Fireplace
Model:
BFC36
For use in the U.S. / Canada
Underwriter’s Laboratories
Report No. MH7603
DO NOT DISCARD THIS MANUAL: Retain for future use.
7412647 5/12 Rev. 20
Homeowner’s Installation and
Operating Manual

2
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
Safety Information ......................................................................................3
Specications and Framing .......................................................................4
Parts Identication ....................................................................................6
Chimney Requirements ............................................................................7
Planning Information ..................................................................................8
Installation .................................................................................................9
Replacement Parts ..................................................................................19
Accessories .............................................................................................21
Warranty...................................................................................................23
Table of Contents
BFC36
Listed
UL127 / ULC-S610
Standard for Factory Built Fireplaces

3
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
Safety Information
Please Read This Manual Before Installing and Using Fireplace
IMPORTANT: Read all instructions and warnings carefully before starting installation. Failure to follow these instruc-
tions may result in a possible re hazard and will void the warranty.
Description
The BFC36 replace is a solid fuel, woodburning re-
place. The BFC36 is a balanced ue (closed combus-
tion) heat-circulating replace which receives outside
combustion air through the chimney system. This
unique system results in much higher efciency since
valuable room air is not used for combustion.
The BFC36 is a decorative replace which provides
efcient supplemental heat compared to other wood
burning replaces. It should not be used as a primary
source of heat.
CAUTION: Overloading the rebox with wood may re-
sult in overring and damage to refractory components,
the grate and doors.
Precautions
MHSC replaces and component parts have been
thoroughly tested and will operate safely when installed
in accordance with instructions provided in this manual.
Carefully read and understand all instructions before
beginning installation.
If you notice any damage to replace or component
parts, immediately report damage to your MHSC dealer.
Only use MHSC components or the warranty will be
voided and a re hazard may be created.
MHSC warranty will be voided by and MHSC disclaims
any responsibility for the following actions:
• Installation by any other than a qualied
installer, preferably NFI or WETT (Canada)
certied.
• Installation of any damaged replace or chim-
ney component;
• Modication of replace, chimney assembly
or any component parts thereof; (except for
chase ashings as detailed in MHSC Chimney
Top installation instructions).
• Installation other than as instructed by MHSC;
or
• Installation and/or use of any component part
not manufactured or approved by MHSC in
combination or assembly with a MHSC re-
place system, notwithstanding any indepen-
dent testing laboratory or other third party
approval of such component parts or acces-
sory.
Any such action may possibly cause a re hazard.
Consult local building codes to ensure that you are in
compliance before installing the replace.
This replace and chimney system must be vented to
the out-of-doors.
Do not obstruct or modify air inlets/outlets in any
manner.
Do not install combustible materials on any of the
black replace surround.
Burn only solid wood fuel or gas logs.
The BFC36 is intended for operation only with the
doors closed.
Do not install a solid fuel burning insert or other
products not specied for use with this replace.
Drafts
The replace should not be located in areas that create
drafts (ie: frequently opened doors and central heating
air inlets/outlets) that hamper the normal ow of air into
the re.
Gas Logs
If you plan to install a gas log, the gas line should be
installed before framing the replace. The gas line must
be installed by a certied gas line installer.
Proposition 65 Warning: Fuels used in gas, wood-
burning or oil red appliances, and the products of
combustion of such fuels, contain chemicals known
to the State of California to cause cancer, birth de-
fects and other reproductive harm.
California Health & Safety Code Sec. 25249.6
WARNING: Check with your electronics manufac-
turer before installing a television or other electron-
ic device above this replace.

4
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
BFC36 Balanced Flue Heat-Circulating Fireplace
Fig. 1 BFC36 specications and framing.
6" (16mm)
56O" (13mm)
56O"
326"
(829mm)
41(6" (1064mm)
6"
(16mm)
56QE"
(49mm)
" (914mm)
"
(533mm)
56QE" (176mm)
56QE" (179mm)
Recessed
Nailing
Flange
647
BFC36 specs
8/18/00 djt
1356O" Dia.
(343mm)
Rough Opening Width 43"
Rough
Opening
Height
Rough
Opening
Depth
Gas Line
Access
5156QE" (1297mm)
5156QE"
(1297mm)
6QE" (1834mm)
6M"
(197mm)
23"
(584mm)
"
(610mm)
6QE"
(624mm)
3956M"
(997mm)
556QE"
(246mm)
35"
(889mm)
"
(279mm)
Gas Line
Access
56O"
(902mm)
36"
(914mm)
(1092mm)
11" Dia.
(179mm)
8" Dia.
(203mm)
56" (918mm)
A
B
C
FP1531
hearth dimensions
9/04 djt
Front Width Back Width Depth
A B C
BFC36 32Z\x" 20M\zn" 17C\v"
(826 mm) (519 mm) (451 mm)
FP1531
Fig. 1a Hearth dimensions.

5
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
FP554a
BFC
Fireplace and chase parts identification
circulating model
8/21/00 djt
Termination Cap
Storm Collar
Pan Flashing
Draftstop
Standoff
Surround
Trim Ledge
Standoff
Glass Door
Romex Pigtail
Gas Line Access Knock-
out (Each Side)
Air Inlet
Basket Grate
Bottom Grille
Metal Safety Strip(s)
Shown not inplace
(1,2 or 3 pieces)
Nailing Flange
Top Grille and Air Outlet
Gas Line Ac-
cess Hole
(Each Side)
Ceiling Level
Firestop
Batt Insulation
(Cut out around
restop)
FP554c
Fig. 2 Fireplace and chase parts identication.

6
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
D
Rise
BG
H
B
Offset
C
E
6 FT.
G
H
A
Hearth
Floor
Chimney
Section
CHIMNEY FLUE EXIT
Elbow
FP269
MBUF
5/16/96
rev. 5/25
TCS8A
Support
Example 1 Example 2 Example 3
Chimney Requirements - Offset Installations
Notes: G + H cannot exceed 20 feet.
Air Space Clearances: = 2” Min. to Combustibles
Illustration Key
The following safety rules apply to
offset installations (letters correspond
with illustration above):
A. Height of the chimney is measured
from the hearth to the chimney exit.
BFC36
Maximum: 50’0”
Minimum:
Without Elbows 14’6”
With 2 Elbows* 14’6”
With 4 Elbows* 21’0”
B. Do not use more than 4 elbows per
chimney.
Attach the straps of the return (top)
elbow to a structural framing member.
The offset (rst) elbow of any pair does
not have straps.
FP269
C. The chimney cannot be more than 30˚
(45˚ in Canada) from the vertical plane in
any installation*.
D. The maximum length of the angled run
of the total chimney system is 20 feet. (G
plus H cannot exceed 20 feet.)
E. A chimney support (Model TCS8A)
is required every 6 feet of angled run of
chimney. Chimney supports are required
for every 30 feet and 60 feet of vertical
chimney height above the hearth.
Determine the offset distance of your
chimney arrangement from the centerline
of the replace to the centerline of the
chimney where it is to pass through the
rst ceiling.
NOTE: This offset distance may not be
your full offset distance. See Examples 2
and 3.
Fig. 3 Chimney system requirements.
IWF282
0 0 0 0 0 3” 11”
1 0 0 0 0 8Z\v" 20"
0 1 0 0 0 11Z\v" 25Z\v"
2 0 0 0 0 13Z\x" 29Z\v"
1 1 0 0 0 16Z\x" 34Z\v"
0 0 1 0 0 20Z\v" 40C\v"
2 1 0 0 0 21C\v" 43Z\x"
0 0 0 1 0 26Z\v" 51Z\v"
0 1 1 0 0 28Z\x" 55Z\v"
1 0 0 1 0 31Z\x" 60Z\v”
0 1 0 1 0 34Z\x" 65Z\x"
0 0 2 0 0 37Z\x" 70C\v"
1 1 0 1 1 41Z\x" 77C\v"
0 0 1 1 1 45" 83C\v"
0 1 2 0 1 47Z\v" 87Z\x"
0 0 0 2 1 51" 94"
0 1 1 1 1 53Z\v" 98"
0 0 3 0 1 56Z\v" 103Z\v"
0 1 0 2 1 59Z\v" 108Z\x"
0 0 2 1 1 62Z\v" 113Z\x"
0 1 3 0 1 64Z\x" 117Z\x"
0 0 1 2 1 68Z\v" 124"
0 1 2 1 1 70Z\x" 128"
0 0 0 3 1 74Z\v" 134Z\x"
0 1 1 2 2 78" 140C\v"
0 0 3 1 2 81" 146"
0 1 0 3 2 84" 151Z\v"
0 0 2 2 2 87" 156Z\x"
0 1 3 1 2 89Z\v" 160Z\v"
0 0 1 3 2 93" 166C\v"
0 1 2 2 2 95Z\v" 170C\v"
0 0 0 4 2 99Z\v" 177C\v"
0 1 1 3 2 101Z\v" 181C\v"
0 0 3 2 2 104Z\v" 186Z\v"
0 1 0 4 2 107Z\v" 191Z\x"
0 0 2 3 2 110Z\v" 196C\v"
0 1 3 2 3 114" 203Z\v"
0 0 1 4 3 117C\v" 209C\v"
0 1 2 3 3 120" 213Z\x"
0 0 0 5 3 123C\v" 220"
30˚ Elbow Offsets
1’ 1¹⁄₂'3’ 4’
Chimney Support
Offset Rise
FP282
MBUF
5/26/96
Offset
Rise
30°
Return
Elbow
30°
Return
Elbow
30°
Offset
Elbow
30°
Offset
Elbow

7
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
Planning Information
Preplanning an installation is very important to ensure
safety and to save time and money. An installer must
predetermine where a replace will be set and how the
chimney system will be run.
Mounting the Fireplace
A replace may only be mounted on the following sur-
faces:
1. A at combustible surface.
2. A raised wooden platform.
3. A concrete block or other solid object placed be-
neath each of the four (4) corners of the replace.
The replace must be spaced 1” (25mm) from a com-
bustible back wall and 1/2” (13mm) from a combustible
side wall or support. (Page 13, Fig. 17)
Planning the Chimney Run
Determine how the chimney will be run, length of run
and chimney components required to complete the
job. (Fig. 4) Never install a chimney below minimum
heights.
In planning a chimney system, it is important to know:
1. The height of a chimney is measured from the
hearth to the exit point on the termination.
2. A chimney cannot be offset more than 30° from a
vertical plane.
3. A chimney may run straight up or it may be neces-
sary to offset it to avoid obstructions.
4. The maximum length of an angled run (total chimney
system) is 20’ (6m).
5. No more than 2 offsets (4 total 30° elbows in U.S./or
2 total 45° elbows in Canada) per replace may be
used.
6. A guy wire stabilizer is required for chimneys extend-
ing more than 6’ (1.8m) above a roof line.
The Ten Foot Rule
Major U.S. building codes specify a minimum chimney
height above the roof top. The “Ten Foot Rule” is a re
safety rule and not a draft rule. To ensure proper draft,
it is recommended that you always meet or exceed the
“Ten Foot Rule,” especially when installing a termination
on a high pitch roof. (Fig. 5)
The key points of the “Ten Foot Rule” are:
1. If the horizontal distance from the chimney to the
peak of the roof is 10’ (3m) or less, the top of the
chimney must be at least 2’ (610mm) above the peak
of the roof, but never less than 3’ (914mm) in height
above the highest point where it passes through the
roof.
2. If a horizontal distance from the chimney to the peak
of the roof is more than 10’ (3m), a chimney height
reference point is established on the surface of the
roof a distance of 10’ (3m) from the chimney in a
horizontal plane. The top of the chimney must be
at least 2’ (610mm) above the reference point, but
never less than 3’ (914mm) in height above the high-
est point where it passes through the roof.
L1
L1
LTTOTAL
LENGTH
(LT)
INSTALLED
LENGTH
(L1)
56O"
56O"
56O"
56O"
56O"
56O"
56O"
56O"
FP288A
MBUF-INSTALLED LENGTH
Triple wall
1/28/99 djt
TRIPLE
WALL
81
818
83
84
FP288a
Fig. 4 Installed lengths of chimney sections.
2' Min.
2' Min.
3'
Min.
0 To 10'
3'
Min.
0 To 10'
AC246
4/1/96

Reference
Point
AC246
Fig. 5 Ten Foot Rule illustration.

8
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
Chimney Supports
The chimney system is supported by the replace for
vertical chimney heights less than 30’ (9m) above the
hearth. Chimney supports are required if the vertical
height exceeds 30’ (9m). Locate chimney supports
at ceiling holes or other structural framing at 30’ (9m)
heights. Spacing between chimney supports must not
exceed 30’ (9m). Use Chimney Support Model TCS8A.
(NOTE: The TCS8A cannot be mounted directly to
the replace.) Support provided by elbow straps fullls
the support requirement only if they are spaced as pre-
viously described. (A chimney support is 2Z\x" (64mm)
long when installed.)
Angled chimney runs require a support every 6’ 1.8m)
in addition to the elbow straps. Chimney supports are
used for this function. (Fig. 6)
FP284a
TCS8A
8/21/00
Chimney Sup-
port Strap
TCS8A FP284a
Fig. 6 Chimney support installation.
Chase Installation
A chase is a vertical box-like structure which encloses
the replace and/or chimney. Chases are typically built
on the outside of the house with replace opening cut
into the outer wall of a room. (Page 4, Fig. 2)
If you need help in determining replace location or how
the chimney system should be run, contact your MHSC
dealer for assistance.
Installation
Insulating Fireplace Enclosure
for Cold Climates
If you live in a cold climate, it is not required but
highly recommended that you insulate replace
enclosure to eliminate cold air penetration as much
as possible.
Insulate base of replace with a noncombustible
insulation rated for a minimum of 300°F. Insulating
is very important for outside wall installations over
a concrete slab. If replace is installed on a platform,
insulation should be placed on top of the platform
before replace is set. (Fig. 7)
When a replace is installed in a chase or on a
outside wall, enclosure should be treated like any
outside wall in a home. Insulation should be installed
on the inside wall as well as the outside wall(s). In
a chase, it is also a good idea to install a restop at
the rst ceiling level above the replace and enclose
the chase with sheeting material. Insulation may
then be installed above sheeting material to assure
the space around the replace is totally protected.
(Fig. 2)
When installing the chimney, DO NOT caulk be-
tween outer pipe and restop. It is vital that some air
be allowed to ow through this very thin gap.
CAUTION: When installing a replace in an insu-
lated enclosure, be sure all required air spaces
are maintained. (Page 13, Fig. 17)

9
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
FPC555a
Platform insulation
BFC model
8/21/00 djt
Hard Flat
Surface
Insulation
Platform
FPC555a
Fig. 7 Insulating between platform and replace.
Framing
Framing can be constructed before or after the replace
is set in place, however, most installers build the frame
before setting the replace.
Frame replace with 2 x 4 lumber or heavier materi-
als. Refer to framing dimensions in Figure 1 for basic
replace specications.
NOTE: Framing should be positioned to accommodate
wall covering and replace facing material.
Electrical Wire Installation
The fan requires 120V AC, 60 Hz power which may be
connected from the right side of the replace. This pow-
er connection must be completed before the replace is
secured and nish material applied.
The lower cavity of the replace may be accessed by
removing the lower grille. Lift grille and pull lower side
out to remove.
1. If using romex type power supply wiring, install a
strain relief tting into the small access hole in the
lower right side of the replace outer wrapper.
2. Route house power wires into the replace through
the tting.
3. Extend these wires through large front hole of right
side oor support.
4. Using supplied junction box assembly, connect and
secure house romex wiring to duplex outlet. Ensure
correct polarity and that the ground wire is securely
connected.
5. Secure romex wiring using supplied strain relief
tting at rear of junction box. Re-assemble junction
box.
6. Secure romex wiring at strain relief tting in replace
outer wrapper.
7. Mount junction box mounting plate to inside face of
right side oor support using two self-tapping sheet
metal screws.
8. Plug blower cord into duplex outlet.
9. Replace lower grille.
Chimney Set-up
Since you have already preplanned the chimney run,
you should know exactly how the installation is to
be accomplished — how much pipe is required, the
number of elbows, if any, and type of termination to be
used.
CAUTION: REPORT TO YOUR DEALERS ANY
PARTS DAMAGED IN SHIPMENT, SPECIFICALLY
CHECK THE END CONNECTION OF CHIMNEY SEC-
TIONS AND ELBOWS.
NOTE: The BFC36 replace must use MHSC Model
triple wall 8” chimney components only. The installation
procedure described in this manual applies only to this
system.
Straight-Up Chimney Installation
To mark the centerline of the ue, put the replace in
nal position and measure out from the wall: 8C\v" (222
mm). Mark a spot on the ceiling directly above the re-
place. Draw a line parallel to the back wall through this
mark. (Fig. 8)
Using a plumb bob positioned directly over center point
of replace ue collar, mark the ceiling to establish the
chimney center point. (Fig. 8)
Offset Installation
In order to clear an obstruction, it may be necessary to
offset chimney from vertical. This is accomplished by
using elbows. Use the 30° Offset Elbow table on Page
5 to determine proper offset and parts required.
Each offset requires two (2) elbows. The second elbow
is equipped with support straps. It is very important to
install the second elbow in each offset as close to the
ceiling or support as possible so that the elbow straps
can be secured to framing members to help support the
weight of the chimney.

10
BFC36 Balanced Flue Heat-Circulating Fireplace
7412647
Determine offset distance of your chimney arrangement
from centerline of replace to centerline of chimney
where it is to pass through ceiling.
Locate center point of the chimney on ceiling as though
a straight up chimney arrangement is to be used. Mea-
sure your offset dimension from straight up chimney
center point on ceiling.
Ceiling Chimney Hole/
Possible Obstructions
The size of the hole in ceiling will vary with the angle at
which the chimney passes through ceiling.
Drive a nail up through ceiling at marked chimney cen-
ter point. Go to oor above and see where hole will be
cut. Check to see where existing ceiling joists and other
possible obstructions are located...i.e. wiring, plumbing
etc... If necessary, re-position chimney and/or replace
to avoid obstructions.
FPC556a
BFC36
LOCATE CENTER LINE
Circulating model
8/21/00 djt
86M"
(222mm)
Chimney Centerline
Actual Center-
point
Plumb Line
Plumb Bob
Imaginary Center-
point
FPC556a
Fig. 8 Locate centerline of chimney with plumb line.
New
Framing
Members
Existing
Ceiling
Joists
Fig. 9 Typical frame for ceiling chimney hole.
FP551b
17 1/2"
Framing chimney hole
5/13/99 djt
Ceiling
Chimney
Hole
17Z\x”
(445mm) 17Z\x”
(445mm)
FP551b
Fig. 10 Ceiling chimney hole sizes necessary for installing
restop spacer.
Cutting the Hole
Cover replace collar opening and cut proper sized
chimney hole in chimney.
Framing the Ceiling Hole
Frame the ceiling chimney hole as shown in Figure 9. It
is good practice to use framing lumber that is the same
size as the ceiling joists; this is a requirement at attic
level.
The following table gives restop spacer model num-
bers:
Chimney Hole Size
Angle of Chimney
at Ceiling
Size of Chimney Vertical 30°
FS2A FS6A
8” Flue 17Z\x” x 17Z\x” 17M\₈” x 29⁵\₈”
(445 x 445mm) (454 x 753mm)
The inside dimension of the frame must be the same
as the hole size selected from Figure 10 in order to
provide required the 2” (51mm) air space between the
outside diameter of the chimney and the edges of the
framed ceiling hole.