Superior MHW36R, MHW36CB Installation And Operation Instructions Manual

Installation and Operation Instructions

PFS

Superior® Clean-Face Round Back Fireplace
with Bi-Fold Doors and Combustion Air Kit

P/N 127312-01 Rev. D 10/2025

®

P127312-01

USC

Models

MHW36R

SAVE THIS BOOK

This book is valuable. In addition to instructing you on how to install and maintain your appliance, it also
contains information that will enable you to obtain replacement parts or accessory items when needed. Keep
it with your other important papers.

INSTALLER: Leave this manual with the appliance.
CONSUMER: Retain this manual for future reference.

Installateur : Laissez cette notice avec l’appareil.
Consommateur : Conservez cette notice pour consultation ultérieure.

This wood burning fireplace complies with UL127
CAN/ULC-S610-M87 standard as a FACTORY
BUILT FIREPLACE.

This fireplace is approved for use as a wood burning fireplace or for use with a vented gas log approved to
ANSI Z21.60 or Z21.84 standards or for use with a vent-free gas log heater approved to ANSI Z21.11.2 standard

An IHP hood must be installed when using a vent-free log heater (see Accessories, page 19).
FOR CANADA: The authority having jurisdiction

(such as the municipal building department, fire
department, etc.) should be contacted before
installation to determine the need to obtain a permit.

This installation manual will enable you to obtain a safe, efficient and dependable installation of your fireplace
system. Please read and understand these instructions before beginning your installation.

Do not alter or modify the fireplace or its components under any circumstances. Any modification or alteration of
the fireplace system, including but not limited to the fireplace, chimney components and accessories, may void the
warranty, listings and approvals of this system and could result in an unsafe and potentially dangerous installation.

IMPORTANT! TO ASSURE PROPER ALIGNMENT OF GLASS DOORS: INSTALL THIS FIREPLACE IN A SQUARE
AND PLUMB CONDITION, USING SHIMS AS NECESSARY AT SIDES AND/OR BOTTOM.

Ce foyer au bois est conforme aux UL 127 CAN/ULC­S610-M87 norme comme une USINE CONSTRUITE
CHEMINÉE.

.

POUR LE CANADA: L’autorité compétente (comme le
service municipal du bâtiment, les pompiers, etc.) doit
être contacté avant l’installation afin de déterminer la
nécessité d’obtenir un permis.

TABLE OF CONTENTS

Safety ................................................................................................... 2

Fireplace Installation ............................................................................ 2

Venting Installation .............................................................................. 6

Optional Gas Line Installation ............................................................ 13

Finishing Fireplace ............................................................................. 15

Operation and Maintenance Guidelines .............................................. 15

Technical Service ...............................................................................17

Replacement Parts ............................................................................. 17

Accessories ........................................................................................ 18

Important Notices .............................................................................. 21

Warranty ............................................................................................ 23

CAUTION

Thestructural integrityof the mobilehome oor

and ceiling/roof must be maintained.

WARNING

Do not install a fireplace insert in this box unless
the manufacturer's instructions with the insert
specifically state this fireplace has been tested for
use with the insert.

FOR YOUR SAFETY

SAFETY

WARNING

Improper installation, adjustment, alteration,
service or maintenance can cause injury, property
damage or loss of life. Refer to this manual for
assistance or additional information. Consult a
qualified installer or local distributor.

IMPORTANT: Check HUD requirements before installing this
fireplace.

These units are intended for installation in manufactured (mobile) homes.
These units may also be installed in buildings of conventional construction
including modular housing, providing all instructions provided herein
are strictly adhered to. These fireplaces include a combustion air kit and
bi-fold doors.

Before beginning the installation of the fireplace, read these instructions
through completely.

• ThisIHPreplaceanditscomponentsaresafewheninstalledaccord-

ingtothisinstallationmanual.UnlessyouuseINNOVATIVEHEARTH
PRODUCTS(IHP)approvedcomponents,whichhavebeendesigned

and tested for the fireplace system, you may cause a fire hazard.

• TheIHPwarrantywillbevoidedbyandIHPdisclaimsanyresponsibil­ity for the following actions.
a. Modification of the fireplace, components, doors, air inlet system and

damper control.

b. UseofanycomponentpartnotmanufacturedorapprovedbyIHP

incombinationwithanIHPreplacesystem.

• Donotstoreorusegasolineoranyotherammablevapors

or liquids in the vicinity of this or any other appliance.

• Duetohightemperatures,theapplianceshouldbelocated

out of traffic and away from furniture and draperies.

• Donotplaceclothingorotherammablematerialsonor

near the appliance.

• Neverleavechildrenunattendedwhenareisburningin

the fireplace.

This fireplace is not intended to be used as a substitute for a
furnace to heat an entire home. Use for supplemental heat only.

This wood burning fireplace complies with the UL 127 standard
as a FACTORY BUILT FIREPLACE and is listed and tested by the
PFS Corporation.

FIREPLACE INSTALLATION

SELECTING LOCATION

To determine the safest and most efficient location for the fireplace, you
must take into consideration the following guidelines:

1. The location must allow for proper clearances (see Figures 2 and 3,
page 4).

2. Consider a location where the heat output will not be affected by
drafts, air conditioning ducts, windows or doors.

3. A location that avoids the cutting of joists or roof rafters will make
installation easier.

4. An outside air kit is included with this fireplace (see Outside Air Kit on

page 6)

WARNING

Proper installation is the most important step in ensuring safe and con­tinuous operation of the fireplace. Consult the local building codes as to
the particular requirements concerned with the installation of all factory
built fireplaces.

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Do not install this appliance in a bedroom.

SPECIFICATIONS

Round Top Termination

Storm Collar

Flashing

42"

1

/4"

36

J-Box
Access

RH SIDE VIEW

3

7

/4"

36"

1"

41"

Gas Line Conduit
Sleeve (Both Sides)

22

3

6

3"

0" To Top

1/2" Air Space

Back and Sides

0" To
Bottom

1

/8"

/4"

Spacer

Firestop
Thimble

221/16"

13"

Firestop

5/8"

1" Airspace

To Combustible

Materials

Combustible
Wall Board

No Combustible
Material On Face

Not Less Than 14"
To Perpendicular
Sidewall

3

9

LH SIDE VIEW

Figure 1 - Specifications

127312-01D

/8"

Rear View
of Fireplace

91/2"

8" Each
Side

14"

14"

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Hearth Extension
52" x 16"

Opening for
Outside Air

3

FIREPLACE INSTALLATION

Effective Height of
Termination Cap

RT-8DM

30E-8DM

40' Max.

Height

20' for

Manufactured

Home

Application

Continued

WARNING

42 1/4"

3

41

/4"

Figure 2 - Framing Dimensions

Maintain 1/2" Air Space
between surface of

Maintain 1/2" Air Space

framing, insulation, and

Between Framing

drywall.

and Fireplace

13" Min.

43

22

Min.

5

/8"

10"

Do not pack required air spaces with insulation or
other materials.

MINIMUM/MAXIMUM CHIMNEY HEIGHT

Minimum height of the chimney, measured from base of fireplace to flue
gas outlet of termination, is 14 feet* for straight flue or a flue with one
elbow set. Maximum distance between elbows is 2 feet.

Maximum height of any system is 40 feet.* This measurement includes
fireplace, chimney sections and height of termination assembly at level
of flue gas outlet (see Figure 5).

Effective Height of
Termination Cap

5

/8"

14' Min.

Height

11' for

Manufactured

Home

Application

RT-8DM

Effective Height of
Termination Cap

14' Min.

Height

11' for

Manufactured

Home

Application

RT-8DM

41 3/4" Min.

61

11/16" Min.

Figure 3 - Corner Installation

MINIMUM CLEARANCE TO COMBUSTIBLES

Back and sides of fireplace 1/2" minimum*
Floor under fireplace** 0" minimum
Wall to front of fireplace 36" minimum
Perpendicular wall to opening 14" minimum
Top spacers 0" minimum
Mantel clearances see Mantels, page 15
Chimney outer pipe surfaces 1" minimum

* Not required at nailing flanges
** See step 2 of Framing, page 5

2' Max

Pipe Length

Figure 4

*For manufactured home application, minimum height is 11' for straight
flue or flue with one elbow set. Maximum height of any system is 20'.

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FIREPLACE INSTALLATION

Continued

Standard

Installation

RT-8DM

Alternate

Installation

Effective Height of
Termination Cap

40' Max.

Height

20' for

Manufactured

Home

Application

FRAMING

1. Frame opening for fireplace using dimensions shown in Figures 2
and 3.

2. The fireplace may not be installed on carpeting, tile or any combustible
material other than wood flooring, fireplace must be installed on a
metal or wood panel extending full width and depth of fireplace. (It is
acceptable to cover two outside ends or columns of top louver panel
leaving four center columns open).

3. Set fireplace directly in front of this opening and slide unit back until
nailing flanges touch side framing.

4. Check level of fireplace and shim with sheet metal if necessary.

5. Before securing fireplace to prepared framing, metal ember protector
(provided) must be placed between hearth extension (not supplied)
and under bottom front edge of fireplace to protect against glowing
embers falling through. If fireplace is to be installed on a raised plat­form, a Z-type ember protector (not supplied) must be fabricated to fit
your required platform height. Ember protector should extend under
fireplace a minimum of 1-1/2". The ember protector should be made
of metal material.

6. Using screws or nails, secure fireplace to framing through flanges
located on sides of fireplace (see Figure 6).

Alternate

30E-8DM

Installation

Figure 5 - Standard and Alternate Venting Installation

Nailing
Flange

Screw or
Nail

Figure 6 - Nailing Flanges

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5

FIREPLACE INSTALLATION

Continued

HEARTH EXTENSION

A hearth extension projecting a minimum of 16" in front of and a minimum
of 8" beyond each side of the fireplace opening is required to protect
combustible floor construction in front of the fireplace. Use an equal mate­rial which meets the following specifications: a layer of noncombustible,
inorganic material having a thermal conductivity of k = .84 BTU IN/FT2

HR°F(orless)at1"thick.Forexample,ifthematerialselectedhasak

factor of 0.25, such as glass fiber, the following formula would apply:

0.25 x 1.0" = 0.30" thickness required

0.84

Thermal conductivity "k" of materials can be obtained from the manufac­turer or supplier of the noncombustible material. If the hearth extension
is to be covered, use noncombustible material such as tile, slate, brick,
concrete, metal, glass, marble, stone, etc. Provide a means to prevent
hearth extension from shifting and seal gap between fireplace frame and
hearth extension with a noncombustible material (see Figure 7).

Fireplace
Front

Ember
Protector

Fireplace Front
Elevated

Seal Gap

Seal Gap

Ember
Protector

Hearth
Extension

WARNING

Hearth extension is to be installed only as shown
in Figure 7.

VENTING INSTALLATION

OUTSIDE AIR KIT

Installation of an outside air kit should be completed during the rough
framing of fireplace due to nature of its location. The supplied flex duct
measures approximately 10" compressed and up to approximately 36"
extended. Outside combustion air is accessed through mobile home floor
using air kit model AK6E, included with the fireplace, or a side wall using
optional air kit model AK6-WE (see Accessories on page 19).

Insert Inner Tab of Inlet Tube into
Slot on Outer Surround

Insulation

Figure 7 - Hearth Extension

Installer may choose either left or right side mounting to allow for
proper wall/rafter clearances.

For AK6-WE Only: Construct a 4-1/2" x 4-1/2" framing or opening on
exterior wall (see Figure 8, page 6).

For AK6E Only: The outside air vent is installed through a ventilated crawl
space (see Figure 9, page 7).

Air Vent Location Must
Allow for Bushes, Snow
and Other Possible
Obstructions

Left Side
Mounting Shown

Secure to Collar with Metal
Tape, Screws or Tie Straps

Figure 8 - Outside Air Kit AK6-WE Installation

Outside Air Vent
Termination

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VENTING INSTALLATION

Continued

1. Locate and remove air inlet cover plate on fireplace‘s outer surround.
Save screws.

2. Cut out any visible insulation that may obstruct airflow.

3. Extend flex duct to attach air inlet tube.

4. Insert inner tab of inlet tube into mating slot next to opening.

5. Place outer tab of inlet tube over mating hole next to opening
and secure with screws removed from cover plate in step 1.

6. Install outside air vent termination in a location that will not be
obstructed by bushes, snow, etc. Locate vent near the fireplace
to make flex duct installation easier.

Insert Inner Tab of Inlet Tube
into Slot on Outer Surround

Left Side
Mounting Shown

Insulation

CHIMNEY PIPE

WARNING

Label part number 900599-01 must be applied
by the installer to all chimney pipe sections but
is not required on sections that will be visible
after the installation is complete. Label must
wrap around the circumference of the pipe. See
accessories, page 19 for Kit F2659.

The chimney system approved for this fireplace consists of 12", 18", 24",
36" and 48" snap-lock, double-wall pipe segments, planned for maximum
adaptability to individual site requirements. Actual lengths gained after
fitting overlaps must be taken into consideration (lineal gain) and are
given in the lineal gain chart (see Figure 10). Lineal Gain is the actual
measurable length of a part after two or more parts are connected.

12-3/8" Galvanized
Outer Pipe

Secure to Collar with Metal
Tape, Screws or Tie Straps

Flex Duct Extends
Up to 36"

Figure 9 - Outside Air Kit AK6E Installation

Floor

Hemmed End
8" Stainless
Inner Pipe

LINEAL GAIN

PART NO. DESCRIPTION GAIN

MHW36R Fireplace 42

12-8DM Pipe Section 10-5/8
18-8DM Pipe Section 16-5/8
24-8DM Pipe Section 23-5/8
36-8DM Pipe Section 34-5/8
48-8DM Pipe Section 46-5/8

RTL-8DM Round Termination 7-3/4

* The lineal gain for the terminations is measured to the flue gas
outlet height.

Figure 10 - Lineal Gain

"

"
"
"
"
"

*

"

127312-01D

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7

VENTING INSTALLATION

Continued

There are three vent kits available which have been specially designed
for common installations in manufactured (mobile) homes: MW8K (8'

ventkit),MW9K(9'ventkit)andMW8K-HT(8'HTventkit).Contentsof

these kits are listed under Accessories on page 20. IMPORTANT: If height
of chimney assembly exceeds requirements for transportation of home,
chimney installation may be completed after home is sited.

NOTE: Termination must always be installed after the home is sited.

ASSEMBLY AND INSTALLATION OF DOUBLE WALL CHIMNEY
SYSTEM

Each double wall chimney section consists of a galvanized outer pipe, a
stainless steel inner flue pipe and a wire spacer. Pipe sections must be as­sembled independently as chimney is installed. When connecting chimney
directly to fireplace, inner flue pipe section must be installed first with lanced
side up. Outer pipe section can then be installed over flue pipe section with
hemmed end up. Press down on each pipe section until lances securely
engage hem on fireplace starter. The wire spacer will assure proper spacing
between inner and outer pipe sections.

WARNING

The opening in the collar around the chimney at the
top of the fireplace must not be obstructed. Never
use blown insulation to fill the chimney enclosure.

Flange
End of
Tube

Open End
of Tube

Thimble
Base

Figure 11 - Attaching Adjustable Thimble

Placement
Holes

Continue to assemble chimney sections as outlined above, making sure
that both inner and outer pipe sections are locked together. When install­ing double wall snap-lock chimney together, it is important to assure that
the joint between chimney sections is locked. Check by pulling chimney
upward after locking. Chimney will not come apart if properly locked. It
is not necessary to add screws to keep chimney together (exception, see

Figure 16, page 11).

ADJUSTABLE FIRESTOP THIMBLE

This adjustable thimble adjusts to the most commonly used ceiling
pitches automatically. Refer to the following procedure for installing the
adjustable thimble:

The adjustable thimble may be installed around the chimney components
at assembly or the chimney components may be inserted though the
installed thimble.

Install the thimble from below a finished roof and ceiling assembly. Push
the thimble assembly (tube section first) up into an already prepared open­ing and secure open end of the thimble base to the finished underside of
the roof and ceiling assembly (Figure 11).

Note: The two screws on which the thimble base pivots may be removed
and reinstalled into any of the series of placement holes provided for the
adjustment of the adjustable thimble's point of rotation (Figure 11A).
Adjust the pivot screens to locate the open end of the tube section as
required for the roof line. Additional screws may be placed at the high
and low points of the thimble base in the tabs provided.

Place the thimble base against the finished roof and ceiling assembly and
secure it to the framing with screws or nails. The thimble is self-adjusting
around inserted chimney components. Thimble extensions are available
and may be installed into the adjustable thimble's tube section as needed
to extend the thimble through the roof-line. Secure the thimble extension
to the tube section with screws no more than 1/2" in length.

Pivot
Screw

Figure 11A - Attaching Adjustable Thimble

Position appropriate thimble/firestop spacer combination at ceiling and
nail temporarily with two (2) 8d nails or equivalent fasteners (see Figures
12A, 12B and 12C). Use one fastener on opposite sides to hold thimble/
firestop spacercombination in position. Nail permanently, using at least
two (2) more fasteners, after chimney sections have been assembled
through the thimble/firestop spacer combination and after any neces­sary adjustments
have been made. Firestop spacer must be secured by at least four (4)
fasteners when completely installed.

Note: If there is a room above ceiling level, firestop spacer must be
installed on the bottom side of the ceiling. If an attic is above ceiling
level, firestop thimble must be installed on the bottom side of ceiling
joist (Figure 12).

Note: The installation of the thimble extension is not required in manu­factured homes having ventilated attic spaces, when the chimney height
is equal to or greater than 12 feet.

Ensure the thimble penetrates the roof opening. The thimble must extend
completely through the ceiling or roof cavity to the outermost plane of
the roof. Note: Thimble extensions are available from your dealer for
constructions in which the distance between the outside of the roof and
the inside of the ceiling exceeds 13". The thimbles and their extensions
provide for zero clearances to combustibles and must be used at the
ceiling/roof in manufactured homes (see Figures 12B and 12C, page 9).

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