Lennox ML193DFE Gas Furnace Installation Instructions

© 2020 Lennox Industries Inc.

Dallas, Texas USA

INSTALLATION

INSTRUCTIONS

ML193DFE

MERIT ® SERIES GAS FURNACE

DOWNNFLOW AIR DISCHARGE

507865-02

06/2020

Supersedes 06/2019

THIS MANUAL MUST BE LEFT WITH THE

HOMEOWNER FOR FUTURE REFERENCE

This is a safety alert symbol and should never be ignored. When you see this symbol on labels or in manuals, be alert to the potential for personal injury or death.

CAUTION

As with any mechanical equipment, contact with sharp sheet metal edges can result in personal injury. Take care while handling this equipment and wear gloves and protective clothing.

WARNING

Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Installation and service must be performed by a licensed professional HVAC installer (or equivalent), service agency or the gas supplier.

Contents

Unit Dimensions - inches (mm) ......................................2

ML193DFE Gas Furnace................................................3

Shipping and Packing List ..............................................3

Safety .............................................................................3

Use of Furnace as a Construction Heater ......................4

General ...........................................................................5

Combustion, Dilution, Ventilation Air...............................5

Setting Equipment ..........................................................8

Filters ............................................................................12

Duct System .................................................................12

Pipe Fittings Specifications ...........................................12

Joint Cementing Procedure ..........................................15

Venting Practices ..........................................................15

Gas Piping ....................................................................31

Electrical .......................................................................33

Unit Start-Up .................................................................37

Gas Pressure Measurement.........................................38

Proper Combustion.......................................................39

High Altitude .................................................................39

Testing Non Direct Appliances for Proper Air................40

Other Unit Adjustments.................................................41

Service..........................................................................43

Repair Parts List ...........................................................44

Start Up Checklist .........................................................45

Blower Data ..................................................................48

Page 1

Unit Dimensions - inches (mm)

Flue Condensate Trap Assembly

Furnished for external field installation on either side of unit.

(See installation instructions for additional information.)

A

AIR

B

FLOW

9/16

(14)

9/16

(14)

7

(178)

COMBUSTION

AIR INTAKE

EXHAUST AIR

OUTLET

B

RETURN AIR

OPENING

2-1/16 (52)

1 (25)

Front Panel

5

(127)

2-1/4

(57)

9/16

(14)

TOP VIEW

27-3/4

(705)

19-7/16

(494)

9/16

(14)

33

(838)

2 (51)

Either Side

GAS PIPING INLET

(Either Side)

9-1/8 (232) Right

6-9/16 (167) Left

3/4

(19)

C

Supply

Air

FRONT VIEW

ML193DFE Model No.

045XE36B

070XE6B

090XE48C

3/4

(19)

A in - mm

17-1/2 - 446

21 - 533

B in - mm

16-3/8 - 416

19-7/8 - 505

ELECTRICAL INLET

(Either Side)

CONDENSATE

TRAP CONNECTION

(Either Side)

6-7/16 (163)

Either Side

9 (229)

Either Side

19-1/4

(489)

Supply

Air

SIDE VIEW

3/4

(19)

C in - mm

16 - 406

19-1/2 - 495

Page 2

ML193DFE Gas Furnace

The ML193DFE Category IV gas furnace is shipped ready for installation in the downflow position.

The furnace is equipped for installation in natural gas applications. A conversion kit (ordered separately) is required for use in propane/LP gas applications.

The ML193DFE can be installed as a Direct Vent or

Non- Direct Vent gas central furnace .

NOTE - In Direct Vent installations, combustion air is taken from outdoors and flue gases are discharged outdoors. In

Non-Direct Vent installations, combustion air is taken from indoors or ventilated attic or crawlspace and flue gases are discharged outdoors. See FIGURE 1 and FIGURE 2 for applications involving roof termination.

DIRECT VENT INSTALLATION

EXHAUST OUTLET

COMBUSTION

AIR INTAKE OUTSIDE

OF HOUSE

NON-DIRECT VENT

INSTALLATION

EXHAUST

OUTLET

FIGURE 1

NON-DIRECT VENT

INSTALLATION

EXHAUST

OUTLET

NON-DIRECT VENT

INSTALLATION

EXHAUST

OUTLET

COMBUSTION

AIR INTAKE INSIDE

VENTILATED

ATTIC SPACE

FIGURE 2

COMBUSTION

AIR INTAKE

INSIDE

OF HOUSE

COMBUSTION

AIR INTAKE INSIDE

VENTILATED

CRAWL SPACE

Shipping and Packing List

Package 1 of 1 contains

1 - Assembled ML193DFE unit

1 - Bag assembly containing the following:

1 - Snap bushing

1 - Snap plug

1 - Wire tie

1 - Condensate trap

1 - Condensate trap cap

1 - Condensate trap clamp

1 - 2” diameter Air intake screen

1 - 3/4” Threaded street elbow

Check equipment for shipping damage. If you find any damage, immediately contact the last carrier.

The following items may also be ordered separately:

1 - Thermostat

1 - Propane/LP changeover kit

Safety Information

Danger of explosion.

DANGER

There are circumstances in which odorant used with LP/ propane gas can lose its scent. In case of a leak, LP/ propane gas will settle close to the floor and may be difficult to smell. An LP/propane leak detector should be installed in all LP applications.

WARNING

Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Installation and service must be performed by a licensed professional installer (or equivalent), service agency or the gas supplier.

CAUTION

As with any mechanical equipment, contact with sharp sheet metal edges can result in personal injury. Take care while handling this equipment and wear gloves and protective clothing.

Use only the type of gas approved for use with this furnace.

Refer to unit nameplate.

ML193DFE units are CSA International certified to ANSI

Z21.47 and CSA 2.3 standards.

Building Codes

In the USA, installation of gas furnaces must conform with local building codes. In the absence of local codes, units must be installed according to the current National Fuel

Gas Code (ANSI-Z223.1/NFPA 54). The National Fuel

Gas Code is available from the following address:

Page 3

American National Standards Institute, Inc.

11 West 42nd Street

New York, NY 10036

In Canada, installation must conform with current National

Standard of Canada CSA-B149 Natural Gas and Propane

Installation Codes, local plumbing or waste water codes and other applicable local codes.

In order to ensure proper unit operation in non-direct vent applications, combustion and ventilation air supply must be provided according to the current National Fuel Gas

Code or CSA-B149 standard.

Locations and Clearances

This furnace is CSA International certified for installation clearances to combustible material as listed on the unit nameplate and in the table in figure 13. Accessibility and service clearances must take precedence over fire protec tion clearances.

For installation in a residential garage, the furnace must be installed so that the burner(s) and the ignition source are located no less than 18 inches (457 mm) above the floor. The furnace must be located or protected to avoid physical damage by vehicles. When a furnace is installed in a public garage, hangar, or other building that has a hazardous atmosphere, the furnace must be installed according to recommended good practice requirements and current National Fuel Gas Code or CSA B149 standards.

NOTE - Furnace must be adjusted to obtain a temperature rise within the range specified on the unit nameplate. Fail ure to do so may cause erratic limit operation and premature heat exchanger failure.

This ML193DFE furnace must be installed so that its electrical components are protected from water.

Installation in Combination with a Cooling Coil

When this furnace is used with cooling units (FIGURE 3), it shall be installed in parallel with, or on the upstream side of, cooling units to avoid condensation in the heating compartment. With a parallel flow arrangement, a damper

(or other means to control the flow of air) must adequately prevent chilled air from entering the furnace. If the damper is manually operated, it must be equipped to prevent operation of either the heating or the cooling unit, unless it is in the full HEAT or COOL setting.

When installed, this furnace must be electrically grounded according to local codes. In addition, in the United States, installation must conform with the current National Electric Code, ANSI/NFPA No. 70. The National Electric Code

(ANSI/NFPA No. 70) is available from the following address:

National Fire Protection Association

1 Battery March Park

Quincy, MA 02269

In Canada, all electrical wiring and grounding for the unit must be installed according to the current regulations of the Canadian Electrical Code Part I (CSA Standard C22.1) and/or local codes.

GAS UNIT

Dampers

(open during heating operation only)

AIR HANDLER

Dampers

(open during cooling operation only)

FIGURE 3

NOTE - This furnace is designed for a minimum continu ous return air temperature of 60°F (16°C) or an intermittent operation down to 55°F (13°C) dry bulb for cases where a night setback thermostat is used. Return air temperature must not exceed 85°F (29°C) dry bulb.

The ML193DFE furnace may be installed in alcoves, closets, attics, basements, garages, utility rooms and crawl spaces.

This furnace design has not been CSA certified for instal lation in mobile homes, recreational vehicles, or outdoors.

Never use an open flame to test for gas leaks. Check all connections using a commercially available soap solution made specifically for leak detection.

Use of Furnace as Construction Heater

Units may be used for heating of buildings or structures under construction, if the following conditions are met to ensure proper operation:

DO NOT USE THE UNIT FOR CONSTRUCTION HEAT

UNLESS ALL OF THE FOLLOWING CRITERIA ARE

MET :

• Furnace must be in its final location. The vent system must be permanently installed per these installation instructions.

• Furnace must be installed as a two pipe system and one hundred percent (100%) outdoor air must be provided for combustion air requirements during construction.

• A room thermostat must control the furnace. The use of fixed jumpers that will provide continuous heating is prohibited.

• The input rate and temperature rise must be set per the furnace rating plate.

• Supply and Return air ducts must be provided and sealed to the furnace. Return air must be terminated outside of the space where furnace is installed.

• Return air temperature range between 60°F (16°C) and

80°F (27°C) must be maintained.

Page 4

• MERV 11 or greater air filters must be installed in the system and must be regularly inspected and maintained

(e.g., regular static checks and replaced at end of life) during construction.

• Blower and vestibule access panels must be in place on the furnace at all times.

• The furnace heat exchanger, components, duct system, and evaporator coils must be thoroughly cleaned following final construction clean−up.

• Air filters must be replaced upon construction comple tion.

• All furnace operating conditions (including ignition, input rate, temperature rise and venting) must be verified in accordance with these installation instructions.

EQUIPMENT MAY EXPERIENCE PREMATURE COM-

PONENT FAILURE AS A RESULT OF FAILURE TO FOL-

LOW THE ABOVE INSTALLATION INSTRUCTIONS.

FAILURE TO FOLLOW THE ABOVE INSTALLATION IN-

STRUCTIONS VOIDS THE MANUFACTURER’S EQUIP-

MENT LIMITED WARRANTY. LENNOX DISCLAIMS

ALL LIABILITY IN CONNECTION WITH INSTALLER’S

FAILURE TO FOLLOW THE ABOVE INSTALLATION IN-

STRUCTIONS .

NOTWITHSTANDING THE FOREGOING, INSTALLER

IS RESPONSIBLE FOR CONFIRMING THAT THE USE

OF CONSTRUCTION HEAT IS CONSISTENT WITH THE

POLICIES AND CODES OF ALL REGULATING ENTI-

TIES. ALL SUCH POLICIES AND CODES MUST BE AD-

HERED TO.

General

These instructions are intended as a general guide and do not supersede local codes in any way. Consult authorities having jurisdiction before installation.

In addition to the requirements outlined previously, the following general recommendations must be considered when installing a ML193DFE furnace:

• Place the furnace as close to the center of the air distribution system as possible. The furnace should also be located close to the chimney or vent termination point.

• When the furnace is installed in non-direct vent applications, do not install the furnace where drafts might blow directly into it. This could cause improper combustion and unsafe operation.

• When the furnace is installed in non-direct vent applications, do not block the furnace combustion air opening with clothing, boxes, doors, etc. Air is needed for proper combustion and safe unit operation.

• When the furnace is installed in an attic or other insulated space, keep insulation away from the furnace.

• When the furnace is installed in an unconditioned space, consider provisions required to prevent freezing of condensate drain system.

CAUTION

ML193DFE unit should not be installed in areas normally subject to freezing temperatures.

Combustion, Dilution & Ventilation Air

If the ML193DFE is installed as a Non-Direct Vent Furnace, follow the guidelines in this section.

NOTE - In Non-Direct Vent installations, combustion air is taken from indoors or ventilated attic or crawlspace and flue gases are discharged out-doors.

WARNING

I nsufficient combustion air can cause headaches, nausea, dizziness or asphyxiation. It will also cause excess water in the heat exchanger resulting in rusting and premature heat exchanger failure. Excessive exposure to contaminated combustion air will result in safety and performance related problems. Avoid exposure to the following substances in the combustion air supply:

Permanent wave solutions

Chlorinated waxes and cleaners

Chlorine base swimming pool chemicals

Water softening chemicals

De-icing salts or chemicals

Carbon tetrachloride

Halogen type refrigerants

Cleaning solvents (such as perchloroethylene)

Printing inks, paint removers, varnishes, etc.

Hydrochloric acid

Cements and glues

Antistatic fabric softeners for clothes dryers

Masonry acid washing materials

In the past, there was no problem in bringing in sufficient outdoor air for combustion. Infiltration provided all the air that was needed. In today’s homes, tight construction practices make it necessary to bring in air from outside for combustion. Take into account that exhaust fans, appliance vents, chimneys, and fireplaces force additional air that could be used for combustion out of the house. Unless outside air is brought into the house for combustion, negative pressure (outside pressure is greater than inside pressure) will build to the point that a downdraft can occur in the furnace vent pipe or chimney. As a result, combustion gases enter the living space creating a potentially dangerous situation.

In the absence of local codes concerning air for combustion and ventilation, use the guidelines and procedures in this section to install ML193DFE furnaces to ensure effi cient and safe operation. You must consider combustion air needs and requirements for exhaust vents and gas piping. A portion of this information has been reprinted with permission from the National Fuel Gas Code (AN-

SIZ223.1/ NFPA 54). This reprinted material is not the complete and official position of the ANSI on the refer enced subject, which is represented only by the standard in its entirety.

In Canada, refer to the CSA B149 installation codes.

Page 5

CAUTION

Do not install the furnace in a corrosive or contaminated atmosphere. Meet all combustion and ventilation air requirements, as well as all local codes.

All gas-fired appliances require air for the combustion process. If sufficient combustion air is not available, the furnace or other appliance will operate inefficiently and unsafely. Enough air must be provided to meet the needs of all fuel-burning appliances and appliances such as exhaust fans which force air out of the house. When fireplac es, exhaust fans, or clothes dryers are used at the same time as the furnace, much more air is required to ensure proper combustion and to prevent a downdraft. Insuffi cient air causes incomplete combustion which can result in carbon monoxide.

In addition to providing combustion air, fresh outdoor air dilutes contaminants in the indoor air. These contaminants may include bleaches, adhesives, detergents, solvents and other contaminants which can corrode furnace components.

The requirements for providing air for combustion and ventilation depend largely on whether the furnace is installed in an unconfined or a confined space.

Unconfined Space

An unconfined space is an area such as a basement or large equipment room with a volume greater than 50 cubic feet (1.42 m3) per 1,000 Btu (.29 kW) per hour of the combined input rating of all appliances installed in that space.

This space also includes adjacent rooms which are not separated by a door. Though an area may appear to be unconfined, it might be necessary to bring in outdoor air for combustion if the structure does not provide enough air by infiltration. If the furnace is located in a building of tight construction with weather stripping and caulking around the windows and doors, follow the procedures in the air from outside section.

Confined Space

A confined space is an area with a volume less than 50 cubic feet (1.42 m3) per 1,000 Btu (.29 kW) per hour of the combined input rating of all appliances installed in that space. This definition includes furnace closets or small equipment rooms.

When the furnace is installed so that supply ducts carry air circulated by the furnace to areas outside the space containing the furnace, the return air must be handled by ducts which are sealed to the furnace casing and which terminate outside the space containing the furnace. This is especially important when the furnace is mounted on a platform in a confined space such as a closet or small equipment room. Even a small leak around the base of the unit at the platform or at the return air duct connection can cause a potentially dangerous negative pressure condition. Air for combustion and ventilation can be brought into the confined space either from inside the building or from outside.

Air from Inside

If the confined space that houses the furnace adjoins a space categorized as unconfined, air can be brought in by providing two permanent openings between the two spaces. Each opening must have a minimum free area of 1 square inch (645 mm2) per 1,000 Btu (.29 kW) per hour of total input rating of all gas-fired equipment in the confined space. Each opening must be at least 100 square inches

(64516 mm2). One opening shall be within 12 inches (305 mm) of the top of the enclosure and one opening within 12 inches (305 mm) of the bottom. See FIGURE 4.

EQUIPMENT IN CONFINED SPACE - ALL AIR FROM INSIDE

ROOF TERMINATED

EXHAUST PIPE

SIDE WALL

TERMINATED

EXHAUST PIPE

(ALTERNATE

LOCATION)

OPENINGS

(To Adjacent

NOTE - Each opening shall have a free area of at least one square inch per 1,000 Btu (645mm 2 per .29kW) per hour of the total input rating of all equipment in the enclosure, but not less than 100 square inches

(64516mm.

2).

FIGURE 4

Page 6

Air from Outside

If air from outside is brought in for combustion and ventilation, the confined space shall be provided with two perma nent openings. One opening shall be within 12” (305mm) of the top of the enclosure and one within 12” (305mm) of the bottom. These openings must communicate directly or by ducts with the outdoors or spaces (crawl or attic) that freely communicate with the outdoors or indirectly through vertical ducts. Each opening shall have a minimum free area of 1 square inch per 4,000 Btu (645mm2 per 1.17kW) per hour of total input rating of all equipment in the enclosure. When communicating with the outdoors through horizontal ducts, each opening shall have a minimum free area of 1 square inch per 2,000 Btu (645mm2 per .59kW) per total input rating of all equipment in the enclosure (FIGURE 5). It is also permissible to bring in air for combustion from a ventilated attic (FIGURE 6) or ventilated crawl space (FIGURE 7.

EQUIPMENT IN CONFINED SPACE - ALL AIR FROM OUTSIDE

(Inlet Air from Crawl Space and Outlet Air to Outside)

VENTILATION LOUVERS

(Each end of attic)

ROOF TERMINATED

EXHAUST PIPE

If air from outside is brought in for combustion and ventilation, the confined space must have two permanent open ings. One opening shall be within 12 inches (305 mm) of the top of the enclosure and one opening within 12 inches

(305 mm) of the bottom. These openings must communicate directly or by ducts with the outdoors or spaces

(crawl or attic) that freely communicate with the outdoors or indirectly through vertical ducts. Each opening shall have a minimum free area of 1 square inch (645 mm2) per 4,000 Btu (1.17 kW) per hour of total input rating of all equipment in the enclosure. See FIGURE 5 and FIG-

URE 8. When communicating with the outdoors through horizontal ducts, each opening shall have a minimum free area of 1 square inch (645 mm2) per 2,000 Btu (.56 kW) per total input rating of all equipment in the enclosure. See

FIGURE 9.

EQUIPMENT IN CONFINED SPACE

(Inlet Air from Ventilated Crawlspace and Outlet Air to Outside)

Roof Terminated

Exhaust Pipe

OUTLET

AIR

Ventilation

Louvers

(Crawl space)

Furnace

Inlet Air

(Minimum

12 in.(305mm)

Above crawl space floor)

SIDE WALL

TERMINATED

EXHAUST PIPE

(ALTERNATE

LOCATION)

FURNACE

INLET

AIR

NOTE-The inlet and outlet air openings shall each have a free area of at least one square inch per 4,000 Btu (645mm 2 per 1.17kW) per hour of the total input rating of all equipment in the enclosure.

FIGURE 5


(Inlet Air from Ventilated Attic and Outlet Air to Outside)

Roof Terminated

Exhaust Pipe

Ventilation Louvers

Inlet Air

(Minimum

12 in.(305mm) Above attic floor)

*Intake Debris

Screen

(Provided)

Furnace

Coupling or

3 in. to 2 in.

Transition

(Field Provided)

*Intake Debris Screen Provided)


FIGURE 7

When ducts are used, they shall be of the same cross-sectional area as the free area of the openings to which they connect. The minimum dimension of rectangular air ducts shall be no less than 3 inches (75 mm). In calculating free area, the blocking effect of louvers, grilles, or screens must be considered. If the design and free area of protective covering is not known for calculating the size opening required, it may be assumed that wood louvers will have

20 to 25 percent free area and metal louvers and grilles will have 60 to 75 percent free area. Louvers and grilles must be fixed in the open position or interlocked with the equipment so that they are opened automatically during equipment operation.


FIGURE 6

Page 7

EQUIPMENT IN CONFINED SPACE - ALL AIR FROM OUTSIDE

(All Air Through Ventilated Attic)

ROOF TERMINATED

EXHAUST PIPE

VENTILATION LOUVERS

(Each end of attic)

OUTLET

AIR

SIDE WALL

TERMINATED

EXHAUST PIPE

(ALTERNATE

LOCATION)

FURNACE

INLET AIR

(Ends 12” above bottom)


FIGURE 8

EQUIPMENT IN CONFINED SPACE -

ALL AIR FROM OUTSIDE

Shipping Bolt Removal

Units with 1/2 and 3/4 hp blower motor are equipped with three flexible legs and one rigid leg. The rigid leg is equipped with a shipping bolt and a flat white plastic wash er (rather than the rubber mounting grommet used with a flexible mounting leg). See FIGURE 10.

The bolt and washer must be removed before the furnace is placed into operation. After the bolt and washer have been removed, the rigid leg will not touch the blower housing.

Units with 1/2 or 3/4 HP Blower Motor

RIGID LEG remove shipping bolt and washe

OUTLET AIR

SIDE WALL

TERMINATED

EXHAUST PIPE

(ALTERNATE

LOCATION)

FURNACE

INLET AIR

NOTE-Each air duct opening shall have a free area of at least one square inch per 2,000 Btu (645mm 2 per .59kW) per hour of the total input rating of all equipment in the enclosure. If the equipment room cate directly with the outdoors, each opening shall have a free area of at least 1 square inch per 4,000 Btu (645mm 2 per 1.17kW) per hour of the total input rating of all other equipment in the enclosure.

FIGURE 9

FIGURE 10

Installation - Setting Equipment

WARNING

Do not install the furnace on its front, back or in the horizontal position. See FIGURE 12. Do not connect the return air ducts to the back of the furnace. Doing so will adversely affect the operation of the safety control devices, which could result in personal injury or death.

Select a location that allows for the required clearances that are listed on the unit nameplate. Also consider gas supply connections, electrical supply, vent connection, condensate trap and drain connections, and installation and service clearances [24 inches (610 mm) at unit front].

The unit must be level from side to side. Unit may be positioned from level to 1/2” toward the front to aid in draining. See FIGURE 11.

Page 8

Allow for clearances to combustible materials as indicated on the unit nameplate. Minimum clearances for closet or alcove installations are shown in FIGURE 13.

WARNING

Blower access panel must be securely in place when blower and burners are operating. Gas fumes, which could contain carbon monoxide, can be drawn into living space resulting in personal injury or death.

AIR FLOW

SETTING EQUIPMENT

AIR FLOW AIR FLOW

1/2” max.

FRONT VIEW SIDE VIEW SIDE VIEW

Unit must be level side-to-side. Unit may be positioned from level to 1/2” toward the front to aid in draining.

FIGURE 11

Back Front

NOTE - Do not install the furnace on its front, back or in the horizontal position

Horizontal

FIGURE 12

Page 9

WARNING

Improper installation of the furnace can result in personal injury or death. Combustion and flue products must never be allowed to enter the return air system or air in the living space. Use sheet metal screws and joint tape to seal return air system to furnace. In platform installations with furnace return, the furnace should be sealed airtight to the return air plenum. A door must never be used as a portion of the return air duct system.

The base must provide a stable support and an airtight seal to the furnace. Allow absolutely no sagging, cracks, gaps, etc. For no reason should return and supply air duct systems ever be connected to or from other heating devices such as a fireplace or stove, etc. Fire, explosion, carbon monoxide poisoning, personal injury and/or property damage could result.

The unit may be installed three ways in downflow applica tions: on non-combustible flooring, on combustible floor ing using an additive base, or on a reverse-flow cooling coil cabinet. Do not drag the unit across the floor in the downflow position. Floor and furnace flange damage will result. Refer to FIGURE 13 for clearances in downflow applications.

Downflow Application Installation Clearances

Top

Installation on Non-Combustible Flooring FIGURE 14

1 - Cut floor opening keeping in mind clearances listed on unit rating plate. Also keep in mind gas supply connections, electrical supply, flue and air intake connections and sufficient installation and servicing clearances. See TABLE 1 for correct floor opening size.

2 - Flange warm air plenum and lower the plenum into the opening.

3 - Set the unit over the plenum and seal the plenum to the unit.

4 - Ensure that the seal is adequate.

TABLE 1

NON-COMBUSTIBLE FLOOR OPENING SIZE

Cabinet

Width

Front to Rear in.

mm

Side to Side in mm

B (17.5”)

C (21”)

19-3/4

19-3 4

502

502

16-5/8

20-1/8

422

511

NOTE - Floor opening dimensions listed are 1/4 inch (6 mm) larger than the unit opening. See dimension drawing on page 2.

FURNACE

PROPERLY

SIZED FLOOR

OPENING

SUPPLY AIR

PLENUM

Left Side Right Side

Bottom

Top

*Front

Back

Sides

0

0†

0

0

Vent

Floor

0

NC

‡

*Front clearance in alcove installation must be 24 in. (610 mm).

Maintain a minimum of 24 in. (610 mm) for front service access.

†Allow proper clearances to accommodate condensate trap and vent pipe installation.

‡ tional base is installed between the furnace and the combustible floor.

FIGURE 13

FIGURE 14

Installation on Combustible Flooring FIGURE 15

1 - When unit is installed on a combustible floor, a downflow combustible flooring base must be installed between the furnace and the floor. The base must be ordered separately. See TABLE 2 for opening size to cut in floor.

CAUTION

The furnace and combustible flooring base shall not be installed directly on carpeting, tile, or other combustible material other than wood flooring.

Page 10

TABLE 2

COMBUSTIBLE FLOORING BASE OPENING SIZE

Cabinet

Width

Catalog

Number

Front to Rear in mm

Side to Side in mm

B (17.5”) 11M60

C (21”) 11M61

22

22

559

559

18-3/4

22-3/4

476

578

FURNACE

COOLING COIL

FURNACE

PROPERLY

SIZED FLOOR

OPENING PLENUM

PROPERLY

SIZED FLOOR

OPENING

SUPPLY AIR

PLENUM

COMBUSTIBLE

FLOORING BASE

FIGURE 15

2 - After opening is cut, set the combustible flooring base into opening.

3 - Check fiberglass strips on the combustible flooring base to make sure they are properly glued and positioned.

4 - Lower supply air plenum into the combustible flooring base until plenum flanges seal against fiberglass strips.

NOTE - Be careful not to damage fiberglass strips.

Check for a tight seal.

5 - Set the furnace over the plenum.

6 - Ensure that the seal between the furnace and plenum is adequate.

Installation on Cooling Coil Cabinet FIGURE 16

NOTE - Downflow combustible flooring kit is not used..

1 - Refer to reverse-flow coil installation instructions for correctly sized opening in floor and installation of cabinet.

2 - When cooling cabinet is in place, set and secure the furnace according to the instructions that are provided with the cooling coil. Secure the furnace to the cabinet.

3 - Seal the cabinet and check for air leaks.

FIGURE 16

Return Air Opening -- Downflow Units

Return air may be brought in only through the top opening of a furnace installed in the downflow position. The follow ing steps should be taken when installing plenum:

1 - Bottom edge of plenum should be flanged with a hemmed edge (See FIGURE 17 or FIGURE 18).

2 - Sealing strips should be used to ensure an airtight seal between the cabinet and the plenum.

3 - In all cases, plenum should be secured to top of furnace using sheet metal screws.

4 - Make certain that an adequate seal is made.

PLENUM

(Field Provided)

SECURE FROM

OUTSIDE CABINET

SEALING STRIP


PLENUM


SECURE FROM

INSIDE CABINET

Side View

FIGURE 17

CABINET

SIDE PANEL

SEALING STRIP


CABINET

SIDE PANEL

Side View

FIGURE 18

Page 11

Filters

This unit is not equipped with a filter or rack. A field-provid ed filter is required for the unit to operate properly. TABLE

3 lists recommended filter size.

A filter must be in place whenever the unit is operating.

IMPORTANT

If a high efficiency filter is being installed as part of this system to ensure better indoor air quality, the filter must be properly sized. High efficiency filters have a higher static pressure drop than standard efficiency glass/foam filters. If the pressure drop is too great, system capacity and performance may be reduced. The pressure drop may also cause the limit to trip more frequently during the winter and the indoor coil to freeze in the summer, resulting in an increase in the number of service calls.

Before using any filter with this system, check the specifications provided by the filter manufacturer against the data given in the appropriate Lennox Product

Specifications bulletin. Additional information is provided in Service and Application Note ACC002

(August 2000).

TABLE 3

Furnace Cabinet Width Minimum Filter Size

17-1/2”

21”

16 x 25 x 1 (1)

Duct System

Use industry-approved standards to size and install the supply and return air duct system. Refer to ACCA Manual

D. This will result in a quiet and low-static system that has uniform air distribution. See FIGURE 19 for proper duct installation.

Supply Air Plenum

If the furnace is installed without a cooling coil, a removable access panel should be installed in the supply air duct. The access panel should be large enough to permit inspection of the heat exchanger. The furnace access panel must always be in place when the furnace is operating and it must not allow leaks into the supply air duct system.

NOTE - This furnace is not certified for operation in heat ing mode (indoor blower operating at selected heating speed) with an external static pressure which exceeds 0.5 inches w.c. Operation at these conditions may result in improper limit operation.

Duct Installation

Down-Flow Unit

SUPPLY

AIR

FIGURE 19

Return Air Plenum

NOTE - Return air must not be drawn from a room where this furnace, or any other gas-fueled appliance (i.e., water heater), or carbon monoxide-producing device (i.e., wood fireplace) is installed.

When return air is drawn from a room, a negative pressure is created in the room. If a gas appliance is operating in a room with negative pressure, the flue products can be pulled back down the vent pipe and into the room. This reverse flow of the flue gas may result in incomplete com bustion and the formation of carbon monoxide gas. This raw gas or toxic fumes might then be distributed throughout the house by the furnace duct system.

Use fiberglass sealing strips, caulking, or equivalent seal ing method between the plenum and the furnace cabinet to ensure a tight seal. If a filter is installed, size the return air duct to fit the filter frame.

Pipe & Fittings Specifications

All pipe, fittings, primer and solvent cement must conform with American National Standard Institute and the American Society for Testing and Materials (ANSI/ASTM) standards. The solvent shall be free flowing and contain no lumps, undissolved particles or any foreign matter that adversely affects the joint strength or chemical resistance of the cement. The cement shall show no gelation, stratification, or separation that cannot be removed by stirring.

Refer to the TABLE 4 below for approved piping and fitting materials.

Page 12

CAUTION

Solvent cements for plastic pipe are flammable liquids and should be kept away from all sources of ignition.

Do not use excessive amounts of solvent cement when making joints. Good ventilation should be maintained to reduce fire hazard and to minimize breathing of solvent vapors. Avoid contact of cement with skin and eyes.

TABLE 4

PIPING AND FITTINGS SPECIFICATIONS

Schedule 40 PVC (Pipe) D1785

Schedule 40 PVC (Cellular Core Pipe)

Schedule 40 PVC (Fittings)

Schedule 40 CPVC (Pipe)

Schedule 40 CPVC (Fittings)

SDR-21 PVC or SDR-26 PVC (Pipe)

SDR-21 CPVC or SDR-26 CPVC (Pipe)

Schedule 40 ABS Cellular Core DWV

(Pipe)

Schedule 40 ABS (Pipe)

Schedule 40 ABS (Fittings)

ABS-DWV (Drain Waste & Vent) (Pipe &

Fittings)

PVC-DWV (Drain Waste & Vent) Pipe &

Fittings)

F891

D2466

F441

F438

D2241

F442

F628

D1527

D2468

D2661

D2665

PRIMER & SOLVENT CEMENT

PVC & CPVC Primer

PVC Solvent Cement

CPVC Solvent Cement

ABS Solvent Cement

PVC/CPVC/ABS All Purpose Cement

For Fittings & Pipe of the same material

ABS to PVC or CPVC Transition Solvent

Cement

CANADA PIPE & FITTING & SOLVENT

CEMENT

PVC & CPVC Pipe and Fittings

PVC & CPVC Solvent Cement

ABS to PVC or CPVC Transition

Cement

POLYPROPYLENE VENTING SYSTEM

PolyPro® by Duravent

ASTM

SPECIFICATION

F656

D2564

F493

D2235

D2564, D2235,

F493

D3188

MARKING

ULCS636

InnoFlue® by Centrotherm

IMPORTANT

Exhaust and intake connections are made of PVC. Use

PVC primer and solvent cement when using PVC vent pipe. When using ABS vent pipe, use transitional solvent cement to make connections to the PVC fittings in the unit.

Use PVC primer and solvent cement or ABS solvent cement meeting ASTM specifications, refer to TABLE 4.

As an alternate, use all purpose cement, to bond ABS,

PVC, or CPVC pipe when using fittings and pipe made of the same materials. Use transition solvent cement when bonding ABS to either

PVC or CPVC.

Low temperature solvent cement is recommended during cooler weather. Metal or plastic strapping may be used for vent pipe hangers. Uniformly apply a liberal coat of PVC primer for PVC or use a clean dry cloth for ABS to clean inside socket surface of fitting and male end of pipe to depth of fitting socket.

Canadian Applications Only - Pipe, fittings, primer and solvent cement used to vent (exhaust) this appliance must be certified to ULC S636 and supplied by a single manu facturer as part of an approved vent (exhaust) system. In addition, the first three feet of vent pipe from the furnace flue collar must be accessible for inspection.

Page 13

Input Size

045

070

090

Vent Pipe

Dia. in.

6 1-1/2

2

2-1/2

3

6 1-1/2

2

2-1/2

3

2

2-1/2

3

Flush

Mount Kit

51W11

(US)

51W12

(CA)

3 YES

3 YES

3 YES

3 YES

3 YES

3 YES

3 YES

3 YES

3 YES

3 YES

3 YES

TABLE 5

OUTDOOR TERMINATION USAGE*

STANDARD

Wall Kit

3 inch 2 inch

22G44

(US)

4 30G28

(CA)

44J40 (US)

4 81J20

(CA)

Field

Fabricated

YES

YES

YES

YES

YES

YES

YES

YES

1

1

1

1

1

1

1

1

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

5

5

5

5

5

5

5

5

YES

YES

YES

YES

YES

YES

YES

YES

5 YES

5 YES

5 YES

1-1.2 inch

4

71M80

(US)

44W92

2

2

2

2

2

2

2

2

(CA)

YES

YES

YES

YES

YES

YES

YES

YES

CONCENTRIC

4

2 inch

69M29

(US)

44W92

(CA)

YES

YES

YES

3 inch

60L46 (US)

4 44W93

(CA)

YES

YES

YES

NOTE - Standard Terminations do not include any vent pipe or elbows external to the structure. Any vent pipe or elbows external to the structure must be included in total vent length calculations. See vent length tables.

* Kits must be properly installed according to kit instructions.

1Requires field-provided outdoor 1-1/2” exhaust accelerator.

2Concentric kits 71M80 and 44W92 include 1-1/2” outdoor accelerator, when uses with 045 and 070 input models. When using 1-1/2 inch vent pipe, transistion to 2” pipe before installing concentric kit.

3 Flush mount kits 51W11 and 51W12 includes 1-1/2 in. outdoor exhaust accelerator, required when used with 045, 070 and 090 input models. When using 1-1/2” vent pipe, transition to 2” pipe before installing flushmount kit .

4 Termination kits 30G28, 44W92, 4493 and 81J20 are certified to ULC S636 for use in Canada only.

5 See table 10 for vent accelerator requirements.

6 Requires field provided 2” to 1-1/2” reducer.

Joint Cementing Procedure

All cementing of joints should be done according to the specifications outlined in ASTM D 2855.

NOTE - A sheet metal screw may be used to secure the intake pipe to the connector, if desired. Use a drill or self tapping screw to make a pilot hole.

DANGER

DANGER OF EXPLOSION!

Fumes from PVC glue may ignite during system check.

Allow fumes to dissipate for at least 5 minutes before placing unit into operation.

1 - Measure and cut vent pipe to desired length.

2 - Debur and chamfer end of pipe, removing any ridges or rough edges. If end is not chamfered, edge of pipe may remove cement from fitting socket and result in a leaking joint.

3 - Clean and dry surfaces to be joined.

4 - Test fit joint and mark depth of fitting on outside of pipe.

5 - Uniformly apply a liberal coat of PVC primer for PVC or use a clean dry cloth for ABS to clean inside socket

surface of fitting and male end of pipe to depth of fitting socket.

6 - Promptly apply solvent cement to end of pipe and inside socket surface of fitting. Cement should be applied lightly but uniformly to inside of socket. Take care to keep excess cement out of socket. Apply second coat to end of pipe.

NOTE - Time is critical at this stage. Do not allow primer to dry before applying cement

7 - Immediately after applying last coat of cement to pipe, and while both inside socket surface and end of pipe are wet with cement, forcefully insert end of pipe into socket until it bottoms out. Turn PVC pipe

1/4 turn during assembly (but not after pipe is fully inserted) to distribute cement evenly. DO NOT turn

ABS or cellular core pipe.

NOTE - Assembly should be completed within 20 seconds after last application of cement. Hammer blows should not be used when inserting pipe.

8 - After assembly, wipe excess cement from pipe at end of fitting socket. A properly made joint will show a bead around its entire perimeter. Any gaps may indicate an improper assembly due to insufficient solvent.

9 - Handle joints carefully until completely set.

Page 14

Venting Practices

Piping Suspension Guidelines

SCHEDULE 40

PVC - 5' all other pipe* - 3'

* See Piping and Fittings Specifications table

NOTE - Isolate piping at the point where it exits the outside wall or roof in order to prevent transmission of vibration to the structure.

i n s i d

Wall Thickness Guidelines

24” maximum

3/4” minimum e Wall o u t s i d e

FIGURE 20

REPLACING FURNACE THAT WAS PART OF A

COMMON VENT SYSTEM

CHIMNEY

OR GAS

VENT

(Check sizing for water heater only)

FURNACE

(Replaced)

WATER

HEATER

OPENINGS

(To Adjacent

Room)

If replacing a furnace which was commonly vented with another gas appliance, the size of the existing vent pipe for that gas appliance must be checked. Without the heat of the original furnace flue products, the existing vent pipe is probably oversized for the single water heater or other appliance. The vent should be checked for proper draw with the remaining appliance.

FIGURE 21

1 - In areas where piping penetrates joists or interior walls, hole must be large enough to allow clearance on all sides of pipe through center of hole using a hanger.

2 - When furnace is installed in a residence where unit is shut down for an extended period of time, such as a vacation home, make provisions for draining condensate collection trap and lines.

Exhaust Piping (FIGURE 23 and FIGURE 24)

Route piping to outside of structure. Continue with installation following instructions given in piping termination section.

WARNING

Carbon Monoxide Poisoning Hazard

Cutting or altering exhaust or air intake pipes, which are located in the blower compartment, could result in

Carbon Monoxide Poisoning or Death.

CAUTION

Do not discharge exhaust into an existing stack or stack that also serves another gas appliance. If vertical discharge through an existing unused stack is required, insert PVC pipe inside the stack until the end is even with the top or outlet end of the metal stack.

CAUTION

The exhaust vent pipe operates under positive pressure and must be completely sealed to prevent leakage of combustion products into the living space.

Vent Piping Guidelines

NOTE - Lennox has approved the use of DuraVent® and

Centrotherm manufactured vent pipe and terminations as an option to PVC. When using the PolyPro® by Du raVent or InnoFlue® by Centrotherm venting system the vent pipe requirements stated in the unit installation in struction – minimum & maximum vent lengths, termination clearances, etc. – apply and must be followed. Follow the instructions provided with PoyPro by DuraVent and Inno -

Flue by Centrotherm venting system for assembly or if re quirements are more restrictive. The PolyPro by Duravent and InnoFlue by Centrotherm venting system must also follow the uninsulated and unconditioned space criteria listed in TABLE 9.

The ML193DFE can be installed as either a Non-Direct

Vent or a Direct Vent gas central furnace.

NOTE - In Direct Vent installations, combustion air is taken from outdoors and flue gases are discharged outdoors. In

Non-Direct Vent installations, combustion air is taken from indoors or ventilated attic or crawlspace and flue gases are discharged outdoors.

Intake and exhaust pipe sizing - Size pipe according to

TABLE 6 (minimum) and TABLE 7 (maximum). Count all elbows inside and outside the home.

Page 15

TABLE 6

MINIMUM VENT PIPE LENGTHS

ML193DFE MODEL

045, 070, 090

MIN. VENT LENGTH*

15 ft or 5ft plus 2 elbows or

10 ft plus 1 elbow

* Any approved termination may be added to the minimum length listed. Two 45 degree elbows are the equivalent to one 90 degree elbow.

Regardless of the diameter of pipe used, the standard roof and wall terminations described in section Exhaust Piping

Terminations should be used. Exhaust vent termination pipe is sized to optimize the velocity of the exhaust gas as it exits the termination. Refer to TABLE 10.

In some applications which permit the use of several different sizes of vent pipe, a combination vent pipe may be used. Contact Lennox’ Application Department for assistance in sizing vent pipe in these applications.

IMPORTANT

Do not use screens or perforated metal in exhaust or intake terminations. Doing so will cause freeze-ups and may block the terminations.

Use the following steps in the Piping Size Process to correctly size vent pipe diameter.

NOTE - Lennox offers a glueless vent adapter kit 17H92 as an option for exhaust exiting at the furnace top cap coupling.

Piping Size Process

1

What is the furnace capacity?

2

Which style termination being used?

Standard or concentric?.

3

Which needs most elbows?

Intake or exhaust?

4

How many elbows?

Count all elbows inside and outside house.

5 Desired pipe size?

6

What is the altitude of the furnace installation?

7

Find max intake or exhaust pipe length.

Includes all vent pipe and elbows inside and outside the house.

FIGURE 22

NOTE - It is acceptable to use any pipe size which fits within the guidelines allowed in table 7.

NOTE - All horizontal runs of exhaust pipe must slope back toward unit. A minimum of 1/4” (6mm) drop for each

12” (305mm) of horizontal run is mandatory for drainage.

NOTE - Exhaust pipe MUST be glued to furnace exhaust fittings.

NOTE - Exhaust piping should be checked carefully to make sure there are no sags or low spots.

Page 16

TABLE 7

Maximum Allowable Intake or Exhaust Vent Length in Feet

Intake and Exhaust must be same pipe size.

NOTE - Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.

Standard Termination at Elevation 0 - 10,000 ft.

4

5

6

7

8

9

10

Number

Of 90°

Elbows

Used

1

2

3

Number

Of 90°

Elbows

Used

1

2

3

4

5

6

9

10

7

8

045

20

15

10 n/a

045

15

10 n/a

1-1/2” Pipe

Model

070 090

15

10 n/a

1-1/2” Pipe

Model

070 090

10 n/a n/a n/a

045

36

31

26

61

56

51

46

41

2” Pipe

Model

070

21

16

11

46

41

36

31

26

090

24

19

14 n/a

045

75

70

65

100

95

90

85

80

2-1/2” Pipe

Model

070

55

50

45

80

75

70

65

60

21

16 n/a

60

55

40

35

Concentric Termination Elevation 0 - 10,000 ft.

2” Pipe

Model

2-1/2” Pipe

Model

045

53

48

43

070

38

33

28

090

22

17

12

045

90

85

80

070

70

65

60

38

33

28

23

18

13 n/a

23

18

13 n/a n/a

75

70

65

60

55

50

45

55

50

45

40

35

30

25

090

43

38

33

28

23

18

13 n/a

090

39

34

29

19

14 n/a

96

91

86

81

76

71

66

045

111

106

101

045

102

97

92

87

82

127

122

117

112

107

3” Pipe

Model

070

111

106

101

96

91

86

81

76

71

66

3” Pipe

Model

070

102

97

92

87

82

127

122

117

112

107

89

84

79

74

69

64

59

090

104

99

94

090

83

78

73

68

63

108

103

98

93

88

6

7

8

9

10

1

2

3

4

5

TABLE 8

Maximum Allowable Exhaust Vent Lengths With Furnace Installed in a Closet or Basement Using Ventilated Attic or Crawl Space For

Intake Air in Feet

NOTE - Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.

Standard Termination at Elevation 0 - 10,000 ft.

Number Of

90° Elbows

Used

045

1-1/2” Pipe

Model

070 090 045

2” Pipe

Model

070 090 045

2-1/2” Pipe

Model

070 090 045

3” Pipe

Model

070 090

15

10 n/a

10 n/a n/a

26

21

16

11

6

51

46

41

36

31

36

31

26

21

16

11

6

1 n/a

14

9

4

60

55

50

45

40

85

80

75

70

65

40

35

30

25

20

65

60

55

50

45

28

23

18

8

3 n/a

82

77

72

67

62

107

102

97

92

87

82

77

72

67

62

107

102

97

92

87

63

58

53

48

43

88

83

78

73

68

Page 17

Exhaust

DO NOT transition from larger to smaller pipe in horizontal runs of exhaust pipe.

045/070 Only

1−1/2”

TRANSITION

2”

TYPICAL EXHAUST PIPE CONNECTIONS

2”

2”

2” or

2”

2”

Exhaust

3”

TRANSITION

*2”

DO NOT transition from smaller to larger pipe size in horizontal runs of exhaust pipe.

INTAKE EXHAUST

TOP VIEW

045/070 Only

1−1/2”

TRANSITION

2”

* When transitioning up in pipe size, use the shortest length of 2” PVC pipe possible.

NOTE − Exhaust pipe and intake pipe must be the same diameter.

FIGURE 23

TYPICAL INTAKE PIPE CONNECTIONS

2”

2”

2” or

2”

2”

TRANSITION

3”

*2” 3”

*2”

TRANSITION

*2”

INTAKE

EXHAUST

TOP VIEW

* When transitioning up in pipe size, use the shortest length of 2” PVC pipe possible.

NOTE − Intake pipe and exhaust pipe must be the same diameter.

FIGURE 24

Page 18

Intake Piping

The ML193DFE furnace may be installed in either Direct

Vent or Non-Direct Vent applications. In non-direct vent applications, when intake air will be drawn into the furnace from the surrounding space, the indoor air quality must be considered. Guidelines listed in Combustion, Dilution and

Ventilation Air section must be followed.

Follow the next two steps when installing the unit in Direct

Vent applications, where combustion air is taken from outdoors and flue gases are discharged outdoors. The pro vided air intake screen must not be used in direct vent applications (outdoors).

1 - Use cement to secure the intake pipe to the inlet air connector.

2 - Route piping to outside of structure. Continue with installation following instructions given in general guide lines for piping terminations and intake and exhaust piping terminations for direct vent sections.

Refer to TABLE 7 for pipe sizes.

TYPICAL AIR INTAKE PIPE CONNECTIONS

NON−DIRECT VENT APPLICATIONS

AIR

INTAKE

SCREEN

(Provided)

1 - Use field-provided materials and the factory-provided air intake screen to route the intake piping as shown in FIGURE 25. Maintain a minimum clearance of

3” (76mm) around the air intake opening. The air intake opening (with the protective screen) should always be directed forward, or sideways.

2 - If intake air is drawn from a ventilated attic (FIGURE

26) or ventilated crawlspace (FIGURE 27) the exhaust vent length must not exceed those listed in TABLE 8.

If 3” diameter pipe is used, reduce to 2” diameter pipe at the termination point to accommodate the debris screen.

3 - Use cement to secure the intake pipe to the connector, if desired.

CAUTION

If this unit is being installed in an application with combustion air coming in from a space serviced by an exhaust fan, power exhaust fan, or other device which may create a negative pressure in the space, take care when sizing the inlet air opening. The inlet air opening must be sized to accommodate the maximum volume of exhausted air as well as the maximum volume of combustion air required for all gas appliances serviced by this space.


(Inlet Air from Ventilated Attic and Outlet Air to Outside)

Roof Terminated

Exhaust Pipe

Ventilation Louvers

Inlet Air

(Minimum

12 in.(305mm) Above attic floor)

*Intake Debris

Screen

(Provided)

Furnace

NOTE - Air intake screen and elbow may be rotated, so that screen may be positioned to face forward or to either side.

FIGURE 25

Follow the next two steps when installing the unit in Non-

Direct Vent applications where combustion air is taken from indoors and flue gases are discharged outdoors.


FIGURE 26

Page 19


(Inlet Air from Ventilated Crawlspace and Outlet Air to Outside)

Roof Terminated

Exhaust Pipe

Ventilation

Louvers

(Crawl space)

Furnace

Inlet Air

(Minimum

12 in.(305mm)

Above crawl space floor)

Coupling or

3 in. to 2 in.

Transition

(Field Provided)

*Intake Debris Screen Provided)


FIGURE 27

General Guidelines for Vent Terminations

In Non-Direct Vent applications, combustion air is taken from indoors and the flue gases are discharged to the out doors. The ML193DFE is then classified as a non-direct vent, Category IV gas furnace.

In Direct Vent applications, combustion air is taken from outdoors and the flue gases are discharged to the out doors. The ML193DFE is then classified as a direct vent,

Category IV gas furnace.

In both Non-Direct Vent and Direct Vent applications, the vent termination is limited by local building codes. In the absence of local codes, refer to the current National Fuel

Gas Code ANSI Z223-1/NFPA 54 in U.S.A., and current

CSA-B149 Natural Gas and Propane Installation Codes in

Canada for details.

Position termination according to location given in FIG-

URE 29 or FIGURE 30. In addition, position termination so it is free from any obstructions and 12” above the average snow accumulation.

At vent termination, care must be taken to maintain protective coatings over building materials (prolonged exposure to exhaust condensate can destroy protective coatings). It is recommended that the exhaust outlet not be located within 6 feet (1.8m) of an outdoor AC unit because the condensate can damage the painted coating.

NOTE - See table 9 for maximum allowed exhaust pipe length without insulation in unconditioned space during winter design temperatures below 32°F (0°C). If required exhaust pipe should be insulated with 1/2” (13mm) Ar maflex or equivalent. In extreme cold climate areas, 3/4”

(19mm) Armaflex or equivalent may be necessary. Insu lation must be protected from deterioration. Armaflex with

UV protection is permissable. Basements or other en closed areas that are not exposed to the outdoor ambient temperature and are above 32 degrees F (0°C) are to be considered conditioned spaces.

IMPORTANT

Do not use screens or perforated metal in exhaust terminations. Doing so will cause freeze-ups and may block the terminations.

IMPORTANT

For Canadian Installations Only:

In accordance to CSA International B149 installation codes, the minimum allowed distance between the combustion air intake inlet and the exhaust outlet of other appliances shall not be less than 12 inches (305mm).

Page 20

TABLE 9

Maximum Allowable Exhaust Vent Pipe Length (in ft.) Without Insulation In Unconditioned Space For

Winter Design Temperatures Single - Stage High Efficiency Furnace

Winter Design

Temperatures1

°F (°C)

Vent Pipe

Diameter

045

Unit Input Size

070 090

PVC 2 PP PVC 2 PP PVC 2 PP

32 to 21

(0 to -6)

20 to 1

(-7 to -17)

1-1/2”

2 in

2-1/2 in

3 in

1-1/2”

2 in

2-1/2 in

3 in

1-1/2”

25

18

13

9

15

9

5

1

10

N/A

16

N/A

9

N/A

8

N/A

1

N/A

20

31

24

18

20

18

13

8

15

N/A

28

N/A

18

N/A

16

N/A

8

N/A

N/A

50

42

35

N/A

32

24

19

N/A

N/A

48

N/A

35

N/A

29

N/A

19

N/A

0 to -20

(-18 to -29)

2 in

2-1/2 in

5

1

3

N/A

12

7

10

N/A

22

15

19

N/A

3 in N/A N/A 2 2 10 10

1 Refer to 99% Minimum Design Temperature table provided in the current edition of the ASHRAE Fundamentals Handbook.

2 Poly-Propylene vent pipe (PP) by Duravent and Centrotherm.

NOTE - Concentric terminations are the equivalent of 5’ and should be considered when measuring pipe length.

NOTE - Maximum uninsulated vent lengths listed may include the termination(vent pipe exterior to the structure) and cannot exceed 5 linear feet or the maximum allowable intake or exhaust vent length listed in table 7 or 8 which ever is less.

NOTE - If insulation is required in an unconditioned space, it must be located on the pipe closest to the furnace. See FIGURE 28.

Conditioned

Space

Conditioned

Space

Pipe Insulation

Unconditioned

Space

FIGURE 28

Exhaust

Pipe

Intake

Pipe

Page 21

VENT TERMINATION CLEARANCES

FOR NON-DIRECT VENT INSTALLATIONS IN THE US AND CANADA

INSIDE CORNER

DETAIL

G

A

H

D

E

B

L

F

C

Fixed

Closed

Operable

B

Operable

B

Fixed

Closed

I

M

B

A

J

K

B

A =

VENT TERMINAL

Clearance above grade, veranda, porch, deck or balcony

AIR SUPPLY INLET

US Installations 1

12 inches (305mm) or 12 in. (305mm) above average snow accumulation.

AREA WHERE TERMINAL

IS NOT PERMITTED

Canadian Installations 2


B = Clearance to window or door that may be opened

4 feet (1.2 m) below or to side of opening;

1 foot (30cm) above opening

6 inches (152mm) for appliances <10,000

Btuh (3kw), 12 inches (305mm) for appliances > 10,000 Btuh (3kw) and

<100,000 Btuh (30kw), 36 inches (.9m) for appliances > 100,000 Btuh (30kw)

* 12” C = Clearance to permanently closed window

* 12”

D =

E =

F =

G =

Vertical clearance to ventilated soffit located above the terminal within a horizontal distance of 2 feet (610 mm) from the center line of the terminal

Clearance to unventilated soffit

Clearance to outside corner

Clearance to inside corner

* Equal to or greater than soffit depth.


* No minimum to outside corner

*




*

H =

I = tended above meter / regulator assembly

Clearance to service regulator vent outlet

Clearance to non-mechanical air

* 3 feet (.9m) within a height 15 feet (4.5m) above the meter / regulator assembly

* 3 feet (.9m)

3 feet (.9m) within a height 15 feet (4.5m) above the meter / regulator assembly

3 feet (.9m)

J = pliance

4 feet (1.2 m) below or to side of opening;

1 foot (30 cm) above opening




6 feet (1.8m) K =

L = ply inlet

Clearance above paved sidewalk or paved driveway located on public property

3 feet (.9m) above if within 10 feet

(3m) horizontally

7 feet (2.1m)† 7 feet (2.1m)†

M = Clearance under veranda, porch, deck or balcony

*12 inches (305mm)‡

1

In accordance with the current ANSI Z223.1/NFPA 54 Natural Fuel Gas Code

2

In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code

† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.

‡ Permitted only if veranda, porch, deck or balcony is fully open on a minimum of two sides beneath the floor. Lennox recommends avoiding this location if possible.

12 inches (305mm)‡

*For clearances not specified in ANSI Z223.1/NFPA 54 or CSA

B149.1, clearance will be in accordance with local installation codes and the requirements of the lation instructions.”

FIGURE 29

Page 22

VENT TERMINATION CLEARANCES

FOR DIRECT VENT INSTALLATIONS IN THE US AND CANADA

INSIDE CORNER

DETAIL

G

A

H

D

E

B

L

F

C

Fixed

Closed

Operable

B

Operable

B

Fixed

Closed

I

M

B

J

K

A

B

A =

VENT TERMINAL

Clearance above grade, veranda, porch, deck or balcony

AIR SUPPLY INLET

US Installations 1


AREA WHERE TERMINAL

IS NOT PERMITTED

Canadian Installations 2


B = Clearance to window or door that may be opened

6 inches (152mm) for appliances <10,000 pliances > 10,000 Btuh (3kw) and <50,000 pliances > 50,000 Btuh (15kw)

* 12”




* 12” C = Clearance to permanently closed window

D =

E =

F =

G =

H =

Vertical clearance to ventilated soffit located above the terminal within a horizontal distance of 2 feet (610mm) from the center line of the terminal

Clearance to unventilated soffit

Clearance to outside corner

Clearance to inside corner

* Equal to or greater than soffit depth



*


* 3 feet (.9m)



*


3 feet (.9m) I = tended above meter / regulator assembly

Clearance to service regulator vent outlet

Clearance to non-mechanical air J = 6 inches (152mm) for appliances <10,000

K =

L =

M = pliances > 10,000 Btuh (3kw) and <50,000 pliance ply inlet

Clearance above paved sidewalk or paved driveway located on public property

Clearance under veranda, porch, deck or balcony pliances > 50,000 Btuh (15kw)

3 feet (.9m) above if within 10 feet

(3m) horizontally

* 7 feet (2.1m)

*12 inches (305mm)‡

1 In accordance with the current ANSI Z223.1/NFPA 54 Natural Fuel Gas Code

2

In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code

† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.

‡ Permitted only if veranda, porch, deck or balcony is fully open on a minimum of two sides beneath the floor. Lennox recommends avoiding this location if possible.




6 feet (1.8m)

7 feet (2.1m)†

12 inches (305mm)‡

*For clearances not specified in ANSI Z223.1/NFPA 54 or CSA

B149.1, clearance will be in accordance with local installation codes and the requirements of the gas supplier and these installation instructions.”

FIGURE 30

Page 23

Details of Intake and Exhaust Piping Terminations for

Direct Vent Installations

NOTE - In Direct Vent installations, combustion air is taken from outdoors and flue gases are discharged to outdoors.

NOTE - Flue gas may be slightly acidic and may adverse ly affect some building materials. If any vent termination is used and the flue gasses may impinge on the building material, a corrosion-resistant shield (minimum 24 inches square) should be used to protect the wall surface. If the optional tee is used, the protective shield is recommend ed. The shield should be constructed using wood, plastic, sheet metal or other suitable material. All seams, joints, cracks, etc. in the affected area should be sealed using an appropriate sealant. See FIGURE 39.

Intake and exhaust pipes may be routed either horizontally through an outside wall or vertically through the roof. In attic or closet installations, vertical termination through the roof is preferred. FIGURE 33 through FIGURE 38 show typical terminations.

1 - Intake and exhaust terminations are not required to be in the same pressure zone. You may exit the intake on one side of the structure and the exhaust on another side (FIGURE 31). You may exit the exhaust out the roof and the intake out the side of the structure (FIGURE 32).

2 - Intake and exhaust pipes should be placed as close together as possible at termination end (refer to illustrations). Maximum separation is 3” (76mm) on roof terminations and 6” (152mm) on side wall terminations.

NOTE - When venting in different pressure zones, the maximum separation requirement of intake and exhaust pipe DOES NOT apply.

3 - terminate straight down using two 90° elbows (See

FIGURE 33).

4 - Exhaust piping must terminate straight out or up as shown. A reducer may be required on the exhaust piping at the point where it exits the structure to improve he velocity of exhaust away from the intake piping. See TABLE 10.

TABLE 10

Exhaust Pipe Termination Size Reduction

ML193DF Model Termination Pipe Size

*045, *070

*090

1-1/2” (38mm)

2” (51mm)

* ML193DFE-045, -070 and -090 units with the flush mount termination must use the 1-1/2” accelerator supplied with the kit.

6 - On field supplied terminations, a minimum distance between the end of the exhaust pipe and the end of the intake pipe without a termination elbow is 8” and a minimum distance of 6” with a termination elbow.

See FIGURE 39.

NOTE - Care must be taken to avoid recirculation of exhaust back into intake pipe.

Exiting Exhaust and Intake Vent

Exhaust

Pipe

Furnace

Inlet Air

(Minimum 12 in.

305 MM) above grade or snow accumulation

FIGURE 31

Exiting Exhaust and Intake Vent

(different pressure zone)

Roof Terminated

Exhaust Pipe

Inches(mm)

(different pressure zone)

8” (203mm) MIN

12” (305mm) ABOVE

AVERAGE SNOW

ACCUMULATION

Furnace

FIGURE 32

3”(76mm) MAX.

3” (76mm) OR

2” (51mm) PVC

PROVIDE SUPPORT

FOR INTAKE AND

EXHAUST LINES

DIRECT VENT ROOF TERMINATION KIT

(15F75 or 44J41)

FIGURE 33

Inlet Air

(Minimum 12 in.

305 MM) above grade or snow accumulation

UNCONDITIONED

ATTIC SPACE

Page 24

7 - If intake and exhaust piping must be run up a side wall to position above snow accumulation or other obstructions, piping must be supported. At least one bracket must be used within 6” from the top of the elbow and then every 24” (610mm) as shown in FIGURE 39, to prevent any movement in any direction. When exhaust and intake piping must be run up an outside wall, the exhaust piping must be terminated with pipe sized per TABLE 10.The intake piping may be equipped with a 90° elbow turndown. Using turndown will add 5 feet (1.5m) to the equivalent length of the pipe.

8 - A multiple furnace installation may use a group of up to four terminations assembled together horizontally, as shown in FIGURE 36.

12” (305mm)

Minimum

Above Average

Snow

Accumulation

Accelerator not required for

3” concentric

INTAKE

FLASHING

(Not Furnished)

CLAMP

SHEET METAL STRAP

(Clamp and sheet metal strap must be field installed to support the weight of the termination kit.)

FIELD-PROVIDED

REDUCER MAY BE REQUIRED

TO ADAPT LARGER VENT

PIPE SIZE TO TERMINATION

DIRECT VENT CONCENTRIC ROOFTOP TERMINATION

71M80, 69M29 or 60L46 (US)

44W92 or 44W93 (Canada)

FIGURE 34

FIELD-PROVIDED

REDUCER MAY BE

REQUIRED TO ADAPT

LARGER VENT PIPE

SIZE TO TERMINATION

OUTSIDE

WALL

EXHAUST

AIR

Accelerator not required for 3” concentric

EXHAUST

AIR

INTAKE

AIR

CLAMP

(Not Furnished)

INTAKE

AIR

12” (305mm) Min.

above grade or average snow ac cumulation.

GRADE

DIRECT VENT CONCENTRIC WALL TERMINATION

71M80, 69M29 or 60L46 (US)

44W92 or 44W93 (Canada)

FIGURE 35

EXHAUST

VENT

INTAKE

AIR

5”

(127mm)

12”

(305mm)

5-1/2”

(140mm)

Inches (mm)

18” MAX.

(457mm)

EXHAUST VENT

Front View

INTAKE

AIR

12” (305mm) Min.

above grade or cumulation.

optional intake elbow

Side View

OPTIONAL VENT TERMINATION FOR MULTIPLE UNIT

INSTALLATION OF DIRECT VENT WALL TERMINATION KIT

(30G28 or 81J20)

FIGURE 36

2” EXTENSION FOR 2” PVC

PIPE1” EXTENSION FOR 3”

PVC PIPE

4''

FURNACE

EXHAUST

PIPE

FURNACE

INTAKE

PIPE

GLUE EXHAUST

END FLUSH INTO

TERMINATION

FLAT

SIDE 1-1/2” ACCELERATOR

FLUSH-MOUNT SIDE WALL TERMINATION KIT

51W11 (US) or 51W12 (Canada)

FIGURE 37

DIRECT VENT APPLICATION

USING EXISTING CHIMNEY

STRAIGHT-CUT OR

ANGLE-CUT IN DIRECTION

OF ROOF SLOPE *

8” - 12”

(203mm - 305mm)

Minimum 12” (305MM) above chimney top plate or average snow accumulation

INTAKE PIPE

INSULATION (optional)

SHEET

METAL TOP

PLATE

3” - 8”

(76mm-

203mm)

SHOULDER OF FITTINGS

PROVIDE SUPPORT

OF PIPE ON TOP PLATE

ALTERNATE

INTAKE PIPE

INSULATE

TO FORM

SEAL

3” - 8”

(76mm-

203mm)

EXTERIOR

PORTION OF

CHIMNEY

NOTE - Do tical discharge through an existing unused chimney or stack is required, insert piping inside trated. In any exterior portion of chimney, the exhaust vent must be insulated.

FIGURE 38

Page 25

FIELD FABRICATED WALL TERMINATION

* WALL

SUPPORT

C1

NOTE − FIELD−PROVIDED

REDUCER MAY BE

REQUIRED TO ADAPT

LARGER VENT PIPE SIZE

TO TERMINATION

C1

E

D

A

B

Intake

Elbow

STRAIGHT

APPPLICATION

C2

D

B

A

EXTENDED

APPLICATION

C2

E

A

D

B

A

2” (51mm)

Vent Pipe

A − Minimum clearance above grade or average snow accumulation

B − Maximum horizontal

separation between

intake and exhaust

C1 -

Minimum from end of exhaust to inlet of intake

C2 -

Minimum from end of exhaust to inlet of intake

12” (305 mm)

6” (152 mm)

8” (203 mm)

6” (152 mm)

3” (76mm)

Vent Pipe

12” (305 mm)

6” (152 mm)

8” (203 mm)

6” (152 mm)

B

D

D − Maximum exhaust pipe length

E − Maximum wall support distance from top of each pipe (intake/exhaust)

12” (305 mm)

6” (152 mm)

20” (508 mm)

6” (152 mm)

See venting table maximum venting lengths with this arrangement.

* Use wall support every 24” (610 mm). Use two wall supports if extension is greater than

24” (610 mm) but less than 48” (1219 mm).

NOTE − One wall support must be within 6” (152 mm) from top of each pipe (intake and exhaust) to prevent movement in any direction.

2

B

B

A

E

C

D

D

ALTERNATE TERMINATIONS (TEE & FORTY−FIVE DEGREE ELBOWS ONLY)

1

1

Intake

Elbow

B

B

A

E

C

D

Exhaust

D

3

2” (51MM)

Vent Pipe

3” (76MM)

Vent Pipe

A − Clearance above grade or average snow accumulation

B − Horizontal separation between intake and exhaust

C − Minimum from end of exhaust to inlet of intake

12” (305 mm) Min. 12” (305 mm) Min.

6” (152 mm) Min.

24” (610 mm) Max.

9” (227 mm) Min.

6” (152 mm) Min.

24” (610 mm) Max.

9” (227 mm) Min.

D − Exhaust pipe length

12” (305 mm) Min.

16” (405 mm) Max.

12” (305 mm) Min.

20” (508 mm) Max.

E − Wall support distance from top of each pipe

(intake/exhaust)

6” (152 mm) Max.

6” (152 mm) Max.

C

Front View of

Intake and Exhaust

12”

2

A

C

A

Intake Exhaust

1 The exhaust termination tee should be connected to the 2” or 3” PVC flue pipe as shown in the illustration.

Do not use an accelerator in applications that include an exhaust termination tee.

The accelerator is not required.

2 As required. Flue gas may be acidic and may adversely affect some building materials. If a side wall vent termination is used and flue gases will impinge on the building materials, a corrosion−resistant shield

(24 inches square) should be used to protect the wall surface. If optional tee is used, the protective shield

3 is recommended. The shield should be constructed using wood, sheet metal or other suitable material.

All seams, joints, cracks, etc. in affected area, should be sealed using an appropriate sealant.

Exhaust pipe 45 ° elbow can be rotated to the side away from the combustion air inlet to direct exhaust away from adjacent property. The exhaust must never be directed toward the combustion air inlet.

FIGURE 39

Page 26

Details of Exhaust Piping Terminations for Non-Direct

Vent Applications

Exhaust pipes may be routed either horizontally through an outside wall or vertically through the roof. In attic or closet installations, vertical termination through the roof is preferred. FIGURE 40 and FIGURE 41 show typical terminations.

1 - Exhaust piping must terminate straight out or up as shown. The termination pipe must be sized as listed in TABLE 10.The Specified pipe size ensures proper velocity required to move the exhaust gases away from the building.

2 - On field supplied terminations for side wall exit, exhaust piping may extend a maximum of 12 inches

(305mm) for 2” PVC and 20 inches (508mm) for 3”

(76mm) PVC beyond the outside wall.

12” (305mm)

ABOVE AVE.

SNOW

ACCUMULATION

3 - If exhaust piping must be run up a side wall to position above snow accumulation or other obstructions, piping must be supported every 24 inches (610mm).

When exhaust piping must be run up an outside wall, any reduction in exhaust pipe size must be done after the final elbow.

Distance between exhaust pipe terminations on multiple furnaces must meet local codes.

Crawl Space and Extended Horizontal Venting

Lennox provides kit 51W18 to install 2” or 3” PVC exhaust piping through the floor joists and into the crawl space.

See FIGURE 42.

This kit can also be used as a supplemental drain for installations with condensate run back in the vent pipe (ie. long horizontal runs, unconditioned spaces, etc.).

Venting In A Crawl Space

3” (76mm) OR

2” (51mm) PVC

PROVIDE SUPPORT

FOR EXHAUST LINES

UNCONDITIONED

ATTIC SPACE

NON-DIRECT VENT ROOF TERMINATION KIT

(15F75 or 44J41)

FIGURE 40

NON-DIRECT VENT APPLICATION

USING EXISTING CHIMNEY

STRAIGHT-CUT OR

ANGLE-CUT IN DIRECTION

OF ROOF SLOPE

Minimum 12” (305MM) above chimney top plate or average snow accumulation

SHEET

METAL TOP

PLATE

INSULATE

TO FORM

SEAL

SHOULDER OF FITTINGS

PROVIDE SUPPORT

OF PIPE ON TOP PLATE

EXTERIOR

PORTION OF

CHIMNEY

NOTE - Do tical discharge through an existing unused chimney or stack is required, insert piping inside trated. In any exterior portion of chimney, the exhaust vent must be insulated.

FIGURE 41

Basement Floor

FIGURE 42

KIT 51W18

(USA)

KIT 15Z70

(CANADA)

Page 27

Condensate Piping

This unit is designed for either right- or left-side exit of condensate piping. Refer to FIGURE 43 and FIGURE 45 for condensate trap locations.

CONDENSATE TRAP AND PLUG LOCATIONS

Trap

(same on right side)

1-1/2 in.

Plug

(same on left side)

Rubber

Grommet

2 - Use a large flat head screw driver or a 1/2” drive socket extension and remove plug (figure 43) from the cold end header box at the appropriate location on the side of the unit. Install provided 3/4 NPT street elbow fitting into cold end header box. Use Teflon tape or appropriate pipe dope.

NOTE - Cold end header box drain plugs are facto ry installed. Check the unused plug for tightness to prevent leakage.

3 - Install the cap over the clean out opening at the base of the trap. Secure with clamp. See FIGURE 49.

4 - Install drain trap using appropriate PVC fittings, glue all joints. Glue the provided drain trap as shown in

FIGURE 49. Route the condensate line to an open drain.

5 - FIGURE 46 shows the furnace and evaporator coil using a separate drain. If necessary, the condensate line from the furnace and evaporator coil can drain together. See FIGURE 47 and FIGURE 48. The field provided vent must be a minimum 1” to a maximum 2” length above the condensate drain outlet connection.

NOTE - If necessary the condensate trap may be installed up to 5 feet away from the furnace. Piping from furnace must slope down a minimum of 1/4” per ft. toward trap.

NOTE - Appropriately sized tubing and barbed fit ting may be used for condensate drain. Attach to the drain on the trap using a hose clamp. See FIGURE

44.

Field Provided Drain Components

FIGURE 43

1 - Determine which side condensate piping will exit the unit, location of trap, field-provided fittings and length of PVC pipe required to reach available drain.

NOTE - Do not remove the rubber grommet used to seal the cabinet on the side not used when installing the condensate trap.

Elbow

Tubing

Barbed Fitting

Hose Clamp

FIGURE 44

Page 28

6 - If unit will be started immediately upon completion of installation, prime trap per procedure outlined in Unit

Start-Up section.

Condensate line must slope downward away from the trap to drain. If drain level is above condensate trap, condensate pump must be used. Condensate drain line should be routed within the conditioned space to avoid freezing of condensate and blockage of drain line. If this is not possible, a heat cable kit may be used on the condensate trap and line. Heat cable kit is available from Lennox in various lengths; 6 ft. (1.8m) - kit no. 26K68 and 24 ft. (7.3m) - kit no. 26K69.

CONDENSATE TRAP LOCATION

(shown with right side exit of condensation)

IMPORTANT

When combining the furnace and evaporator coil drains together, the A/C condensate drain outlet must be vented to relieve pressure in order for the furnace pressure switch to operate properly.

IMPORTANT

Do not use copper tubing or existing copper condensate lines for drain line.

Furnace with Evaporator

Coil Using a Common Drain

Trap can be installed a maximum of 5ft. from furnace (*PVC only)

Field Provided Vent

1” min. 2” max. above condensate drain.

1” min.

2” max.

5’ max.

Field Provided Vent


Condensate

Drain Connection

Evaporator Drain Line

(vent required) to drain

*Piping from furnace must slope down a minimum 1/4” per ft. toward trap

FIGURE 45

Furnace with Evaporator Coil

Using a Separate Drain

Field Provided Vent


Condensate

Drain Connection

FIGURE 47

Condensate Trap With Optional Overflow Switch

From Evaporator Coil

HorizontalFurnace4” Min. to 5” Max.above

condensatedrain connection)

FurnaceCondensate

DrainConnection

Optional

Evaporator Drain Line

(vent required)

Drain

FIGURE 46

FIGURE 48

Page 29

TRAP / DRAIN ASSEMBLY USING 1/2” PVC OR 3/4” PVC

Optional Condensate Drain Connection

Adapter 3/4 inch slip X

3/4 inch mpt (not furnished)

90

°

Street Elbow

3/4 inch PVC

(not furnished)

Adapter 3/4 inch slip X

3/4 inch mpt (not furnished)

Condensate Drain

Connection In Unit

1 (25 mm) Min.

2 (50 mm) Max.

Above Top Of

Condensate Drain

Connection In Unit

Vent

5 Feet

Maximum

90

°

Street Elbow

3/4 inch PVC

( furnished) 90 ° Elbow 3/4 inch PVC

(Not Furnished)

To

Trap

Optional DrainPipingFromTrap

Drain Assembly for 1/2 inch Drain Pipe

1/2 inch PVC Pipe

(Not Furnished)

Condensate Drain

Connection In Unit

3/4 inch PVC Pipe

(Not Furnished)

Coupling 3/4 inch slip X slip

(Not Furnished)

1/2 inch PVC Pipe

(Not Furnished)

To

Drain

90 ° Elbow

1/2 inch PVC

(Not Furnished)

Drain Assembly for 3/4 inch Drain Pipe

Drain Trap

Assembly

(Furnished)

Drain Trap

Clean Out

To

Drain

90 ° Elbow

3/4 inch PVC

(Not Furnished)

90 ° Elbow

3/4 inch PVC

(Not Furnished)

To

Drain

Coupling 3/4 inch slip X slip

(Not Furnished)

DrainTrap Assembly

(Furnished)

DrainTrap Assembly with 1/2 inch Piping

1 (25 mm) Min. 2 (50 mm) Max. Above Top

Of Condensate Drain Connection In Unit

Vent

DrainTrap Assembly with 3/4 inch Piping

1 (25 mm) Min. 2 (50 mm) Max. Above Top

Of Condensate Drain Connection In Unit

Vent

3/4 inch

7

(178)

1/2 inch

Condensate Drain

Connection In Unit

Condensate Drain

Connection In Unit

To

Drain

FIGURE 49

To

Drain

Page 30

Gas Piping

CAUTION

If a flexible gas connector is required or allowed by the authority that has jurisdiction, black iron pipe shall be installed at the gas valve and extend outside the furnace cabinet. The flexible connector can then be added between the black iron pipe and the gas supply line.

WARNING

Do not over torque (800 in-lbs) or under torque (350 inlbs) when attaching the gas piping to the gas valve.

1 - Gas piping may be routed into the unit through either the left- or right-hand side. Supply piping enters into the gas valve from the side of the valve as shown in

FIGURE 51.Connect the gas supply piping into the gas valve. The maximum torque is 800 in lbs and minimum torque is 350 in lbs when attaching the gas piping to the gas valve.

2 - When connecting gas supply, factors such as length of run, number of fittings and furnace rating must be considered to avoid excessive pressure drop.

TABLE 11 lists recommended pipe sizes for typical applications.

NOTE - Use two wrenches when connecting gas piping to avoid transferring torque to the manifold.

3 - Gas piping must not run in or through air ducts, clothes chutes, chimneys or gas vents, dumb waiters or elevator shafts. Center gas line through piping hole. Gas line should not touch side of unit. See

FIGURE 51.

4 - Piping should be sloped 1/4 inch per 15 feet (6mm per 5.6m) upward toward the gas meter from the furnace. The piping must be supported at proper intervals, every 8 to 10 feet (2.44 to 3.05m), using suitable hangers or straps. Install a drip leg in vertical pipe runs to serve as a trap for sediment or condensate.

5 - A 1/8” N.P.T. plugged tap or pressure post is located on the gas valve to facilitate test gauge connection.

See FIGURE 55.

6 - In some localities, codes may require installation of a manual main shut-off valve and union (furnished by installer) external to the unit. Union must be of the ground joint type.

IMPORTANT

Compounds used on threaded joints of gas piping must be resistant to the actions of liquified petroleum gases.

Leak Check

After gas piping is completed, carefully check all piping connections (factory- and field-installed) for gas leaks.

Use a leak detecting solution or other preferred means.

The furnace must be isolated from the gas supply system by closing its individual manual shut-off valve during any pressure testing of the gas supply system at pressures less than or equal to 1/2 psig (3.48 kPa, 14 inches w.c.).

CAP FURNACE

VALVE WILL NOT HOLD

NORMAL TEST PRESSURE

1/8” N.P.T. PLUGGED TAP

FIGURE 50

IMPORTANT

When testing pressure of gas lines, gas valve must be disconnected and isolated. See FIGURE 50. Gas valves can be damaged if subjected to pressures greater than

1/2 psig (3.48 kPa).

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow the safety warnings exactly could result in serious injury, death, or property damage. Never use an open flame to test for gas leaks. Check all connections using a commercially available soap solution made specifically for leak detection. Some soaps used for leak detection are corrosive to certain metals. Carefully rinse piping thoroughly after leak test has been completed.

Page 31

MANUAL

MAIN SHUT-OFF

VALVE

(1/8 in. NPT plugged tap shown)

Left Side Piping

(Standard)

AUTOMATIC

GAS VALVE

(with manual shut-off valve)

AUTOMATIC

GAS VALVE

(with manual shut-off valve)

MANUAL

MAIN SHUT-OFF

VALVE

(1/8 in. NPT plugged tap shown)

GROUND

JOINT

UNION

GROUND

JOINT

UNION

DRIP LEG

FIELD

PROVIDED

AND INSTALLED

NOTE - BLACK IRON PIPE

ONLY

TO BE ROUTED INSIDE OF CABINET

DRIP LEG

Right Side Piping

(Alternate)

FIGURE 51

Nominal

Iron Pipe

Size Inches

(mm)

1/2

(12.7)

3/4

(19.05)

1

(25.4)

1-1/4

(31.75)

1-1/2

(38.1)

2

(50.8)

2-1/2

(63.5)

3

(76.2)

Internal

Diameter inches

(mm)

.622

(17.799)

.824

(20.930)

1.049

(26.645)

1.380

(35.052)

1.610

(40.894)

2.067

(52.502)

2.469

(67.713)

3.068

(77.927)

10

(3.048)

172

(4.87)

360

(10.19)

678

(19.19)

1350

(38.22)

2090

(59.18)

4020

(113.83)

6400

(181.22)

11300

(319.98)

20

(6.096)

118

(3.34)

247

(7.000)

466

(13.19)

957

(27.09)

1430

(40.49)

2760

(78.15)

4400

(124.59)

7780

(220.30)

TABLE 11

Gas Pipe Capacity - ft3/hr (m3/hr)

Length of Pipe - feet (m)

30

(9,144)

95

(2.69)

199

(5.63)

374

(10.59)

768

(22.25)

1150

(32.56)

2220

(62.86)

3530

(99.95)

6250

(176.98)

40

(12,192)

81

(2.29)

170

(4.81)

320

(9.06)

657

(18.60)

985

(27.89)

1900

(53.80)

3020

(85.51)

5350

(151.49)

50

(15.240)

72

(2.03)

151

(4.23)

284

(8.04)

583

(16.50)

873

(24.72)

1680

(47.57)

2680

(75.88)

4740

(134.22)

60

(18.288)

65

(1.84)

137

(3.87)

257

(7.27)

528

(14.95)

791

(22.39)

1520

(43.04)

2480

(70.22)

4290

(121.47)

70

(21.336)

60

(1.69)

126

(3.56)

237

(6.71)

486

(13.76)

728

(20.61)

1400

(39.64)

2230

(63.14)

3950

(111.85)

80

(24.384)

NOTE Capacity given in cubic feet (m3 ) of gas per hour and based on 0.60 specific gravity gas.

56

(1.58)

117

(3.31)

220

(6.23)

452

(12.79)

677

(19.17)

1300

(36.81)

2080

(58.89)

3670

(103.92)

90

(27.432)

635

(17.98)

1220

(34.55)

1950

(55.22)

3450

(97.69)

52

(1.47)

110

(3.11)

207

(5.86)

424

(12.00)

100

(30,480)

50

(1.42)

104

(2.94)

195

(5.52)

400

(11.33)

600

(17.00)

1160

(32.844)

1840

(52.10)

3260

(92.31)

Page 32

Removal of the Furnace from Common Vent

In the event that an existing furnace is removed from a venting system commonly run with separate gas appliances, the venting system is likely to be too large to properly vent the remaining attached appliances. Conduct the following test while each appliance is operating and the other appliances (which are not operating) remain connected to the common venting system. If the venting system has been installed improperly, you must correct the system as indicated in the general venting requirements section.

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow the steps outlined below for each appliance connected to the venting system being placed into operation could result in carbon monoxide poisoning or death.

The following steps shall be followed for each appliance connected to the venting system being placed into operation, while all other appliances connected to the venting system are not in operation:

1 - Seal any unused openings in the common venting system.

2 - Inspect the venting system for proper size and horizontal pitch. Determine that there is no blockage, restriction, leakage, corrosion, or other deficiencies which could cause an unsafe condition.

Close all building doors and windows and all doors between the space in which the appliances remaining connected to the common venting system are located and other spaces of the building. Turn on clothes dryers and any appliances not connected to the common venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, so they will operate at maximum speed. Do not operate a summer exhaust fan. Close fireplace dampers.

4 - Follow the lighting instructions. Turn on the appliance that is being inspected. Adjust the thermostat so that the appliance operates continuously.

5 - After the main burner has operated for 5 minutes, test for leaks of flue gases at the draft hood relief opening. Use the flame of a match or candle.

6 - After determining that each appliance connected to the common venting system is venting properly, (step

3) return all doors, widows, exhaust fans, fireplace dampers, and any other gas-burning appliances to their previous mode of operation.

7 - If a venting problem is found during any of the preceding tests, the common venting system must be modified to correct the problem.

Resize the common venting system to the minimum vent pipe size determined by using the appropriate tables in Appendix G. (These are in the current standards of the National Fuel Gas Code ANSI Z223.1.

Electrical

ELECTROSTATIC DISCHARGE (ESD)

Precautions and Procedures

CAUTION

Electrostatic discharge can affect electronic components. Take precautions to neutralize electrostatic charge by touching your hand and tools to metal prior to handling the control.

WARNING

Electric Shock Hazard. Can cause injury or death. Unit must be properly grounded in accordance with national and local codes.

WARNING

Fire Hazard. Use of aluminum wire with this product may result in a fire, causing property damage, severe injury or death. Use copper wire only with this product.

The unit is equipped with a field make-up box on the left hand side of the cabinet. A field-provided make-up box can be installed on the exterior of the right side of the furnace to facilitate installation. If the make-up box is moved to the right side, clip the wire ties that bundle the wires together and install on the outside of the cabinet. See FIGURE 52.

The excess wire must be pulled into the blower compartment. Secure the excess wire to the existing harness to protect it from damage. Seal unused openings on left side with plugs removed from right side.

EXTERIOR MAKE-UP BOX

(FIELD PROVIDED RIGHT SIDE)

MAKE-UP

BOX

OUTSIDE

CABINET

Right Side

FIGURE 52

Page 33

Refer to FIGURE 53 for field wiring, schematic wiring dia gram and troubleshooting.

The power supply wiring must meet Class I restrictions.

Protected by either a fuse or circuit breaker, select circuit protection and wire size according to unit nameplate.

CAUTION

Failure to use properly sized wiring and circuit breaker may result in property damage. Size wiring and circuit breaker(s) per Product Specifications bulletin (EHB) and unit rating plate.

NOTE Unit nameplate states maximum current draw.

Maximum Over-Current Protection allowed is 15 AMP.

Holes are on both sides of the furnace cabinet to facilitate wiring.

Install a separate (properly sized) disconnect switch near the furnace so that power can be turned off for servicing.

Before connecting the thermostat or the power wiring, check to make sure the wires will be long enough for servicing at a later date. Remove the blower access panel to check the length of the wire.

Complete the wiring connections to the equipment. Use the provided unitw wiring diagram and the field wiring di agram shown in FIGURE 53. Use 18-gauge wire or larger that is suitable for Class II rating for thermostat connections.

Electrically ground the unit according to local codes or, in the absence of local codes, according to the current

National Electric Code (ANSI/NFPA No. 70) for the USA and current Canadian Electric Code part 1 (CSA standard

C22.1) for Canada. A green ground wire is provided in the field make-up box.

NOTE - The ML193DFE furnace contains electronic com ponents that are polarity sensitive. Make sure that the fur nace is wired correctly and is properly grounded.

Accessory Terminals

One line voltage “EAC” 1/4” spade terminal is provided on the furnace integrated control. See FIGURE 54 for integrated control configuration. This terminal is energized when the indoor blower is operating. Any accessory rated up to one amp can be connected to this terminal with the neutral leg of the circuit being connected to one of the provided neutral terminals. If an accessory rated at greater than one amp is connected to this terminal, it is necessary to use an external relay.

One line voltage 120V “HUM” 1/4” spade terminal is provided on the furnace integrated control. See FIGURE 54 for integrated control configuration. This terminal is ener gized in the heating mode when the combustion air inducer is operating. Any humidifier rated up to one amp can be connected to this terminal with the neutral leg of the circuit being connected to one of the provided neutral terminals.

If a humidifier rated at greater than one amp is connected to this terminal, it is necessary to use an external relay.

One 24V ”HUM” 1/4” spade terminal is provided on the furnace integrated control. See FIGURE 54 for integrated control configuration. The terminal is energized in the heating mode when the combustion air inducer is operating and the pressure switch is closed. Any humidifier rated up to 0.5 amp can be connected to this terminal with the ground leg of the circuit connected to ground or the ”C” terminal.

Thermostat

Install the room thermostat according to the instructions provided with the thermostat. See FIGURE 53 for thermostat designations. If the furnace is being matched with a heat pump, refer to the thermostat installation instruction for set up.

Indoor Blower Speeds

1 - When the thermostat is set to “FAN ON,” the indoor blower will run continuously on the (FAN) speed when there is no cooling or heating demand. See

TABLE 19 on page 48 for allowable continuous circulation speeds.

2 - When the ML193DFE is running in the heating mode, the indoor blower will run on the heating speed

(HEAT).

3 - When there is a cooling demand, the indoor blower will run on the cooling speed (COOL).

Generator Use - Voltage Requirements

The following requirements must be kept in mind when specifying a generator for use with this equipment:

• The furnace requires 120 volts + 10% (Range: 108 volts to 132 volts)

• The furnace operates at 60 Hz + 5% (Range: 57 Hz to 63 Hz)

• The furnace integrated control requires both polarity and proper ground. Both polarity and proper grounding should be checked before attempting to operate the furnace on either permanent or temporary power Generator should have a wave form distortion of less than 5% THD (total harmonic distortion).

Page 34

FIGURE 53

Page 35

Integrated Control

INTEGRATED CONTROL

(Automatic Hot Surface Ignition System)

120HUM

LINE

XFMR

CIRC

EAC

NEUTRAL

HUM24

TABLE 12

1/4” QUICK CONNECT TERMINALS

Humidifier 120VAC

120VAC

COOL

HEAT

FAN

PARK (no power)

FLAME / FS

24 COM

Transformer 120VAC

Indoor blower 120VAC

Indoor air quality accessory 120VAC

Common 120VAC

Humidifier 24VAC

3/16” QUICK CONNECT TERMINALS

Cooling tap 24VAC

Heating tap 24VAC

Continuous blower 24 VAC

Park terminal for speed taps

Flame Sense

Common 24VAC

RED LED RECALL BUTTON

FIGURE 54

RED LED Flash Code 2

Off

Heartbeat1

Continuous Rapid Flash

1

2

3

4

7

10

11

8

9

12

13

5

6

BLOWER OFF DELAY

Note - 1

Note - 2

Note - 3

Diagnostic Codes / Status of Furnace

No power to control or board fault detected

Normal Operation - Idle, Continuous Fan, Cool

Call For Heat / Burner Operation

Reverse Line Voltage Polarity

Improper Earth Ground

Burner failed to light, or lost flame during heat demand

Low Flame Signal - check flame sensor

Watchguard - burner failed to light, exceeded maximum number of retries or recycles.

Not Used

Primary or Secondary Limit Open or Watchguard Mode - Limit Switch Open longer than 3 minutes

Rollout Switch Open

Pressure Switch failed to close or opened during heat demand

Watchguard - Pressure Switch opened 5 times during one heat demand

Pressure Switch stuck closed prior to activation of combustion air inducer

Flame Sensed without gas valve energized

Low Line Voltage

Notes

A ”Heartbeat” is indicated by a ”Slow Flash” - 1 sec on 1 sec off, repeating

Error codes are indicated by a “rapid flash” - the LED flashes X times at ½ second on ½ second off, remains off for 3 seconds then repeats.

Last 10 error codes are stored in memory including when power is shut off to the unit. - To recall, press and release button, most recent will be displayed first, LED off for 3 sec, then next error code is displayed, etc. To clear error codes, depress and hold button longer than 5 seconds.

Page 36

Unit Start Up

FOR YOUR SAFETY READ BEFORE OPERATING

WARNING

Electric shock hazard. Can cause injury or death. Do not use this unit if any part has been under water. Immediately call a qualified service technician to inspect the unit and to replace any part of the control system and any gas control which has been under water.

CAUTION

Before attempting to perform any service or maintenance, turn the electrical power to unit OFF at disconnect switch.

WARNING

Danger of explosion. Can cause injury or product or property damage. Should the gas supply fail to shut off or if overheating occurs, shut off the gas valve to the furnace before shutting off the electrical supply.

BEFORE LIGHTING the unit, smell all around the furnace area for gas. Be sure to smell next to the floor because some gas is heavier than air and will settle on the floor.

The gas valve on the ML193DFE is equipped with a gas control switch. Use only your hand to move switch. Never use tools. If the switch will not move by hand, do not try to repair it. Force or attempted repair may result in a fire or explosion.

Placing the furnace into operation:

ML193DFE units are equipped with an automatic hot surface ignition system. Do not attempt to manually light burners on this furnace. Each time the thermostat calls for heat, the burners will automatically light. The ignitor does not get hot when there is no call for heat on these units.

Priming Condensate Trap

The condensate trap should be primed with water prior to start-up to ensure proper condensate drainage. Either pour 10 fl. oz. (300 ml) of water into the trap, or follow these steps to prime the trap:

1 - Follow the lighting instructions to place the unit into operation.

2 - Set the thermostat to initiate a heating demand.

3 - Allow the burners to fire for approximately 3 minutes.

Adjust the thermostat to deactivate the heating demand.

5 - Wait for the combustion air inducer to stop. Set the thermostat to initiate a heating demand and again allow the burners to fire for approximately 3 minutes.

Adjust the thermostat to deactivate the heating demand and wait for the combustion air inducer to stop. At this point, the trap should be primed with sufficient water to ensure proper condensate drain operation.

WARNING

If you do not follow these instructions exactly, a fire or explosion may result causing property damage, personal injury or death.

Gas Valve Operation (FIGURE 55)

1 - STOP!

Read the safety information at the beginning of this section.

2 - Set the thermostat to the lowest setting.

3 - Turn off all electrical power to the unit.

4 - This furnace is equipped with an ignition device which automatically lights the burners. Do not try to light the burners by hand.

5 - Remove the upper access panel.

6 - Move gas valve switch to OFF. See FIGURE 55.

7 - Wait five minutes to clear out any gas. If you then smell gas, STOP! Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions. If you do not smell gas go to next step.

8 - Move gas valve switch to ON. See FIGURE 55.

9 - Replace the upper access panel.

10- Turn on all electrical power to the unit.

11- Set the thermostat to desired setting.

NOTE - When unit is initially started, steps 1 through 11 may need to be repeated to purge air from gas line.

MANIFOLD

PRESSURE

ADJUSTMENT

SCREW

MANIFOLD

PRESSURE

OUTLET

PORT

INLET

PRESSURE

PORT GAS VALVE SHOWN IN ON POSITION

12-

FIGURE 55

If the appliance will not operate, follow the instructions “Turning Off Gas to Unit” and call your service technician or gas supplier.

Turning Off Gas to Unit

1 - Set the thermostat to the lowest setting.

2 - Turn off all electrical power to the unit if service is to be performed.

3 - Remove the upper access panel.

4 - Move gas valve switch to OFF.

5 - Replace the upper access panel.

Page 37

Failure To Operate

If the unit fails to operate, check the following:

1 - Is the thermostat calling for heat?

2 - Are access panels securely in place?

3 - Is the main disconnect switch closed?

4 - Is there a blown fuse or tripped breaker?

5 - Is the filter dirty or plugged? Dirty or plugged filters will cause the limit control to shut the unit off.

6 - Is gas turned on at the meter?

7 - Is the manual main shut-off valve open?

8 - Is the internal manual shut-off valve open?

9 - Is the unit ignition system in lockout? If the unit locks out again, inspect the unit for blockages.

Heating Sequence Of Operation

1 - When thermostat calls for heat, combustion air inducer starts.

Combustion air pressure switch proves blower operation. Switch is factory-set and requires no adjustment.

3 - After a 15-second prepurge, the hot surface ignitor energizes.

4 - After a 20-second ignitor warm-up period, the gas valve solenoid opens. A 4-second Trial for Ignition period begins.”

5 - Gas is ignited, flame sensor proves the flame, and the combustion process continues.

6 - If flame is not detected after first ignition trial, the ignition control will repeat steps 3 and 4 four more times before locking out the gas valve

(“WATCHGUARD” flame failure mode). The ignition control will then automatically repeat steps 1 through

6 after 60 minutes. To interrupt the 60-minute

“WATCHGUARD” period, move thermostat from

“Heat” to “OFF” then back to “Heat”. Heating sequence then restarts at step 1.

Gas Pressure Adjustment

Gas Flow (Approximate)

ML193

Unit

-045

-070

-090

TABLE 13

GAS METER CLOCKING CHART

1 cu ft

Dial

80

Seconds for One Revolution

Natural LP

2 cu ft

Dial

160

1 cu ft

Dial

200

2 cu ft

Dial

400

55

41

110

82

136

102

Natural-1000 btu/cu ft LP-2500 btu/cu ft

272

204

NOTE - To obtain accurate reading, shut off all other gas appliances connected to meter.

Furnace should operate at least 5 minutes before checking gas flow. Determine time in seconds for two revolu tions of gas through the meter. (Two revolutions assures a more accurate time). Divide by two and compare to time in TABLE 13. If manifold pressure matches TABLE 14 and rate is incorrect, check gas orifices for proper size and restriction. Remove temporary gas meter if installed.

Supply Pressure Measurement

A threaded plug on the inlet side of the gas valve provides access to the supply pressure tap. Remove the threaded plug, install a field-provided barbed fitting and connect a manometer to measure supply pressure. See TABLE 14 for proper supply line pressure. Replace the threaded plug after measurements have been taken.

TABLE 14

Supply Line and Manifold Pressure (inches w.c.)

Unit Fuel

Manifold

Pressure

Line Pressure

All Nat. Gas 3.5

4.5 - 10.5

All L.P. Gas 10.0

11.0 - 13.0

NOTE - A natural to L.P. propane gas changeover kit is necessary to convert this unit. Refer to the changeover kit installation instruction for the conversion procedure.

Manifold Pressure Measurement

1 - Connect the test gauge positive side “+“ to manifold pressure tap on gas valve. Connect the test gauge positive side “+“ to manifold pressure tap on gas valve.

2 - Tee into the gas valve regulator vent hose and connect to test gauge negative “-”.

3 - Start unit and let run for 5 minutes to allow for steady state conditions.

4 - After allowing unit to stabilize for 5 minutes, record manifold pressure and compare to value given in

TABLE 14.

5 - Shut unit off and remove manometer as soon as an accurate reading has been obtained. Take care to replace pressure tap plug.

6 - Start unit and perform leak check. Seal leaks if found.

Page 38

Proper Combustion

Furnace should operate minimum 15 minutes with correct manifold pressure and gas flow rate before checking com bustion. Take combustion sample beyond the flue outlet and compare to the table below. The maximum carbon monoxide reading should not exceed 100 ppm.

ML193 Unit

045

070

090

TABLE 15

CO

2

Nat

7.0 - 9.0

CO

2

LP

8.0 - 10.0

The maximum carbon monoxide reading should not exceed 100 pm.

High Altitude Information

NOTE - In Canada, certification for installations at eleva tions over 4500 feet (1372 m) is the jurisdiction of local authorities.

Units may be installed at altitudes up to 10,000 ft. above sea level. See TABLE 16 for de-rate manifold values. Units installed at altitude of 7501 - 10,000 feet require an orifice change. Units installed at altitude of 4501 - 10,000 feet require a pressure switch change which can be ordered separately. TABLE 17 lists conversion kit and pressure switch requirements at varying altitudes.

The combustion air pressure switch is factory-set and requires no adjustment.

NOTE - A natural to LP/propane gas changeover kit is necessary to convert this unit. Refer to the changeover kit installation instruction for the conversion procedure.

TABLE 16

Manifold and Supply Line Pressure 0-10,000ft.

Manifold Pressure in. wg.

ML193E

Unit

All

Sizes

Gas

Natural

L.P. Propane

0 - 4500 ft 4501 - 5500 ft 5501 - 6500 ft 6501 - 7500 ft 7501 - 10,000

3.5

10.0

3.3

9.4

3.2

9.1

3.1

8.9

3.5

10.0

Supply Line Pressure in. w.g.

0 - 10000 ft.

4.5

11.0

13.0

13.0

NOTE - A natural to L.P. Propane gas changeover kit is necessary to convert this unit. Refer to the changeover kit installation instruction for the conversion procedure.

ML193E Unit

TABLE 17

Conversion Kit and Pressure Switch Requirements at Varying Altitudes

Natural to LP/

Propane

0 - 7500 ft

High Altitude

Natural Burner

Orifice Kit

7501 - 10,000 ft

LP/Propane to

Natural

0 - 7500 ft

High Altitude LP/

Propane Burner

Orifice Kit

7501 - 10,000 ft

High Altitude Pressure Switch

4501 - 7500 ft 7501 -10,000 ft

(0 - 2286m) (2286 - 3038m) (0 - 2286m) (2286 - 3038m) (1373 - 2286m) (2286 - 3048m)

-045

-070 *11K49 73W37 *73W81 *11K44 11U65 11U66

-090

* Conversion requires installation of a gas valve manifold spring which is provided with the gas conversion kit. Pressure switch is factory set. No adjustment necessary. All models use the factory-installed pressure switch from 0-4500 feet (0-1370 m).

Page 39

Testing of Non-Direct Vent Applications for Proper

Venting and Sufficient Combustion Air

WARNING

. CARBON MONOXIDE POISONING HAZARD!

Failure to follow the steps outlined below for each appliance connected to the venting system being placed into operation could result in carbon monoxide poisoning or death.

The following steps shall be followed for each appliance connected to the venting system being placed into operation, while all other appliances connected to the venting system are not in operation.

After the ML193DFE gas furnace has been started, the following test should be conducted to ensure proper venting and sufficient combustion air has been provided to the

ML193DFE as well as to other gas-fired appliances which are separately vented.

If a ML193DFE furnace replaces a Category I furnace which was commonly vented with another gas appliance, the size of the existing vent pipe for that gas appliance must be checked. Without the heat of the original furnace flue products, the existing vent pipe is probably oversized for the single water heater or other appliance. The vent should be checked for proper draw with the remaining appliance.

The test should be conducted while all appliances (both in operation and those not in operation) are connected to the venting system being tested. If the venting system has been installed improperly, or if provisions have not been made for sufficient amounts of combustion air, corrections must be made as outlined in the previous section.

1 - Seal any unused openings in the venting system.

2 - Visually inspect the venting system for proper size and

Horizontal pitch. Determine there is no blockage or restriction, leakage, corrosion, or other deficiencies which could cause an unsafe condition.

3 - To the extent that it is practical, close all building doors and windows and all doors between the space in which the appliances connected to the venting system are located and other spaces of the building.

4 - Close fireplace dampers.

5 - Turn on clothes dryers and any appliances not connected to the venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, so they will operate at maximum speed.

Do not operate a summer exhaust fan.

6 - Follow the lighting instruction to place the appliance being inspected into operation. Adjust thermostat so appliance will operate continuously.

7 - Use the flame of match or candle to test for spillage of flue gases at the draft hood relief opening after 5 minutes of main burner operation.

8 - If improper venting is observed during any of the above tests, the venting system must be corrected or sufficient combustion/make-up air must be provided. The venting system should be re-sized to approach the minimum size as determined by using the appropriate tables in appendix G in the current standard of the National Fuel Gas Code ANSI-Z223.1/

NPFA 54 in the U.S.A., and the appropriate Natural

Gas and Propane appliances venting sizing tables in the current standard of the CSA-B149 Natural Gas and Propane Installation Codes in Canada.

9 - After determining that each appliance remaining connected to the common venting system properly vents when tested as indicated in step 3, return doors, windows, exhaust fans, fireplace dampers and any other gas-burning appliance to their previous condition of use.

Page 40

Other Unit Adjustments

Primary Limit

The primary limit is located on the heating compartment vestibule panel. This limit is factory set and requires no adjustment.

Flame Rollout Switches (Two)

These manually reset switches are located on the front of the burner box.

Pressure Switch

The pressure switch is located in the heating compartment on the cold end header box. This switch checks for proper combustion air inducer operation before allowing ignition trial. The switch is factory-set and must not be adjusted.

Temperature Rise

After the furnace has been started and supply and return air temperatures have been allowed to stabilize, check the temperature rise. If necessary, adjust the blower speed to maintain the temperature rise within the range shown on the unit nameplate. See TABLE 18 on page 48 for allowable heating speeds.Increase the blower speed to decrease the temperature. Decrease the blower speed to increase the temperature rise. Failure to adjust the temperature rise may cause erratic limit operation.

Fan Control

The fan on time of 30 seconds is not adjustable. The fan off delay (amount of time that the blower operates after the heat demand has been satisfied) may be adjusted by changing the jumper position across the five pins on the integrated control. The unit is shipped with a factory fan off setting of 120 seconds. The fan off delay affects com fort and is adjustable to satisfy individual applications. Adjust the fan off delay to achieve a supply air temperature between 90° and 110°F at the moment that the blower is de-energized. Longer off delay settings provide lower return air temperatures; shorter settings provide higher return air temperatures. See FIGURE 56.

Thermostat Heat Anticipation

Set the heat anticipator setting (if adjustable) according to the amp draw listed on the wiring diagram that is attached to the unit.

Electrical

1 - Check all wiring for loose connections.

2 - Check for the correct voltage at the furnace (furnace operating).

3 - Check amp-draw on the blower motor.

Motor Nameplate__________Actual__________

HEAT FAN ‐ OFF TIME IN SECONDS

NO JUMPER

To adjust fan-off timing, reposition jumper across pins to achieve desired setting.

60 Second off Time

90 Second off Time

120 Second off Time

180 Second off Time

FIGURE 56

Blower Speeds

Follow the steps below to change the blower speeds.

1 - Turn off electrical power to furnace.

2 - Remove blower access panel.

3 - Disconnect existing speed tap at integrated control speed terminal.

NOTE - Termination of any unused motor leads must be insulated.

4 - Place unused blower speed tap on integrated control

“PARK” terminal or insulate.

5 - Refer to blower speed selection chart on unit wiring diagram for desired heating or cooling speed.

See Product Specifications bulletin for blower performance tables. See TABLE 18 on page 48 for allowable heating speeds.

6 - Connect selected speed tap at integrated control speed terminal.

7 - Re-secure blower access panel.

8 - Turn on electrical power to furnace.

9 - Recheck temperature rise.

Exhaust and Air Intake Pipe

Check exhaust and air intake connections for tightness and to make sure there is no blockage.

2 - Is pressure switch closed? Obstructed exhaust pipe will cause unit to shut off at pressure switch. Check termination for blockages.

3 - Obstructed pipe or termination may cause rollout switches to open. Reset manual flame rollout switches on burner box assembly if necessary.

Page 41

Service

WARNING

. ELECTRICAL SHOCK, FIRE,

OR EXPLOSION HAZARD.

Failure to follow safety warnings exactly could result in dangerous operation, serious injury, death or property damage.

Improper servicing could result in dangerous operation, serious injury, death, or property damage. Before servicing, disconnect all electrical power to furnace.

When servicing controls, label all wires prior to disconnecting. Take care to reconnect wires correctly.

Verify proper operation after servicing.

WARNING

The blower access panel must be securely in place when the blower and burners are operating. Gas fumes, which could contain carbon monoxide, can be drawn into living space resulting in personal injury or death.

Annual Furnace Maintenance

At the beginning of each heating season, and to comply with the Lennox Limited Warranty, your system should be checked as follows:

1 - Check wiring for loose connections, voltage at indoor unit and amperage of indoor motor.

2- Check the condition of the belt and shaft bearings if applicable.

3- Inspect all gas pipe and connections for leaks.

4- Check the cleanliness of filters and change if necessary (monthly).

Check the condition and cleanliness of burners andeat exchanger and clean if necessary.

Check the cleanliness of blower assembly and clean the housing, blower wheel and blower motor if necessary

7- Inspect the condensate drain and trap for leaks and cracks. The drain and trap must also be cleaned and the trap must be primed with water. Inspect the rubber hoses connected to the pressure switches for cracks or loose connections, replace as necessary.

Remove the rubber hoses from the cold end header box and inspect for any blockage, clean as needed.

If strainers are installed in the hoses remember to remove and clean before reinstalling the hoses.

8- Evaluate the heat exchanger integrity by inspecting the heat exchanger per the AHRI heat exchanger inspection procedure. This procedure can be viewed at www.ahrinet.org

9- Ensure sufficient combustion air is available to the furnace. Fresh air grilles and louvers (on the unit and in the room where the furnace is installed) must be properly sized, open and unobstructed to provide combustion air.

10- Inspect the furnace intake and exhaust pipes to make sure they are in place, structurally sound, without holes, blockage or leakage and the exhaust pipe is sloped toward he furnace. Inspect terminations to ensure they are free of obstructions and are structurally sound. Inspect the furnace return air duct connection to ensure the duct is sealed to the furnace. Check for air leaks on supply and return ducts and seal where necessary.

11- Inspect the furnace return air duct connection to ensure the duct is sealed to the furnace. Check for air leaks on supply and return ducts and seal where necessary.

12- Check the condition of the furnace cabinet insulation and repair if necessary.

13- Perform a complete combustion analysis during the furnace inspection to ensure proper combustion and operation. Consult Service Literature for proper combustion values.

Verify operation of CO detectors and replace batteries as required.

Perform a general system test. Turn on the furnace to check operating functions such as the start-up and shutoff operation.

1 - Check the operation of the ignition system, inspect and clean flame sensor. Check microamps before and after. Check controls and safety devices (gas valve, flame sensor, temperature limits). Consult

Service Manual for proper operating range. Thermal

Limits should be checked by restricting airflow and not disconnecting the indoor blower. For additional details, please see Service and Application Note

H049.

2 - Verify that system total static pressure and airflow settings are within specific operating parameters.

3 - Clock gas meter to ensure that the unit is operating at the specified firing rate. Check the supply pressure and the manifold pressure. If manifold pressure adjustment is necessary, consult the Service

Literature for unit specific information on adjusting gas pressure. Not all gas valves are adjustable.

Verify correct temperature rise.

Page 42

Winterizing and Condensate Trap Care

1 - Turn off power to the furnace.

2 - Have a shallow pan ready to empty condensate water.

3 - Remove the clean out cap from the condensate trap and empty water. Inspect the trap then reinstall the drain plug.

Cleaning the Burner Assembly

1 - Turn off electrical and gas power supplies to furnace.

Remove upper and lower furnace access panels.

2 - Disconnect the 2-pin plug from the gas valve.

3 - Remove the burner box cover.

4 - Disconnect the gas supply line from the gas valve.

Remove gas valve/manifold assembly.

5 - Mark and disconnect sensor wire from the sensor.

Disconnect 2-pin plug from the ignitor at the burner box.

Remove four screws which secure burner box assembly to vest panel. Remove burner box from the unit.

7 - Use the soft brush attachment on a vacuum cleaner to gently clean the face of the burners. Visually inspect the inside of the burners and crossovers for any blockage caused by foreign matter. Remove any blockage.

8 - Reconnect the sensor wire and reconnect the 2-pin plug to the ignitor wiring harness.

9 - Reinstall the burner box assembly using the existing four screws. Make sure that the burners line up in the center of the burner ports.

10 Reinstall the gas valve manifold assembly.

Reconnect the gas supply line to the gas valve.

Reinstall the burner box cover.

11 - Reconnect 2-pin plug to gas valve.

12 - Replace the blower compartment access panel.

13 - Refer to instruction on verifying gas and electrical connections when re-establishing supplies.

14 - Follow lighting instructions to light and operate furnace for 5 minutes to ensure that heat exchanger is clean and dry and that furnace is operating properly.

15 - Replace heating compartment access panel

Repair Parts List

The following repair parts are available through Lennox dealers. When ordering parts, include the complete furnace model number listed on the CSA nameplate -- Example: ML193DF045XE36B. All service must be performed by a licensed professional installer (or equivalent), service agency, or gas supplier.

Cabinet Parts

Upper access panel

Blower access panel

Top Cap

Control Panel Parts

Transformer

Integrated control board

Door interlock switch

Blower Parts

Blower wheel

Motor

Motor mounting frame

Motor capacitor

Blower housing cutoff plate

Heating Parts

Flame Sensor

Heat exchanger assembly

Gas manifold

Combustion air inducer

Gas valve

Main burner cluster

Main burner orifices

Pressure switch

Ignitor

Primary limit control

Flame rollout switches

Page 43

Start-Up & Performance Check List

2

2

UNIT SET UP

(typical)

Furnace:

Model Number_______________

Serial Number_________________

Line Voltage

4

1 GAS SUPPLY

Natural Gas LP Propane Gas

Piping Connections Tight

Leak Tested

Supply Line Pressure “W.C.________

1

Gas Supply Pressure

1

SUPPLY

AIR

2 INTAKE / EXHAUST PIPE

All Joints Primed and Glued

Terminations Installed Properly

Horizontal Pipes Sloped (if applicable)

Condensate Trap Primed / Line Sloped

Pipes Supported

Heat Cable Installed and Operable (if applicable)

3

Flter

RETURN AIR

3

DUCT SYSTEM

SUPPLY AIR DUCT

Sealed

Insulated (if necessary)

RETURN DUCT

Sealed

Filter Installed and Clean

4

Grilles Unobstructed

VOLTAGE CHECK

Supply Voltage _____

Electrical Connections Tight

Page 44

1

HEATING MODE

GAS MANIFOLD PRESSURE “W.C._____

UNIT OPERATION

2 COMBUSTION SAMPLE CO

2

%

______

CO PPM_______

3

INDOOR BLOWER AMPS______

4

5

6

7

TEMPERATURE RISE

Supply Duct Temperature ________

Return Duct Temperature _ _____

Temperature Rise = ________

TOTAL EXTERNAL STATIC

Supply External Static _______

Return External Static + ______

Total External Static = _______

CONDENSATE LINE

Leak Free

VENT PIPE

Leak Free

Combustion CO

2

2

7

SUPPLY

AIR

3

COOLING MODE

INDOOR BLOWER AMPS______

4 TEMPERATURE DROP

Return Duct Temperature _________

Supply Duct Temperature _ _______

Temperature Drop = _________

5

8

TOTAL EXTERNAL STATIC (dry coil)

Supply External Static _______

Return External Static + ______

Total External Static = _______

DRAIN LINE

Leak Free

9 THERMOSTAT

Adjusted and Programmed

Explained Operation to Owner

Thermostat

9

Blower Motor Amps

3

6

8

Gas Manifold Pressure

1

Temperatures

4

Duct Static

High +

5

RETURN AIR

Low -

Contractor's: Name_________________________Telephone_____________Checklist Completed____________________

Job Address_____-________________________________Technician's Name___________________________________

Page 45

Requirements for Commonwealth of Massachusetts

Modifications to NFPA-54, Chapter 10

Revise NFPA-54 section 10.8.3 to add the following requirements:

For all side wall, horizontally vented, gas-fueled equipment installed in every dwelling, building or structure used in whole or in part for residential purposes, including those owned or operated by the Commonwealth and where the side wall exhaust vent termination is less than seven (7) feet above the finished grade in the area of the venting, in cluding but not limited to decks and porches, the following requirements shall be satisfied:

INSTALLATION OF CARBON MONOXIDE

DETECTORS. At the time of installation of the side wall, horizontally vented, gas-fueled equipment, the installing plumber or gasfitter shall observe that a hard-wired carbon monoxide detector with an alarm and battery backup is installed on the floor level where the gas equipment is to be installed.

In addition, the installing plumber or gasfitter shall observe that a battery-operated or hard-wired carbon monoxide detector with an alarm is installed on each additional level of the dwelling, building or structure served by the side wall, horizontally vented, gas-fueled equipment. It shall be the responsibility of the property owner to secure the services of qualified licensed professionals for the installation a. In the event that the side wall, horizontally vented, gas-fueled equipment is installed in a crawl space or an attic, the hardwired carbon monoxide detector with alarm and battery backup may be installed on the next adjacent floor level.

b. In the event that the requirements of this subdivision cannot be met at the time of completion of installation, the owner shall have a period of thirty (30) days to comply with the above requirements; provided, however, that during said thirty (30) day period, a battery-operated carbon monoxide detector with an alarm shall be installed.

2 - APPROVED CARBON MONOXIDE DETECTORS.

Each carbon monoxide detector as required in accordance with the above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and IAS certified.

3 - SIGNAGE. A metal or plastic identification plate shall e permanently mounted to the exterior of the building at a minimum height of eight (8) feet above grade directly in line with the exhaust vent terminal for the horizontally vented, gas-fueled heating appliance or equipment. The sign shall read, in print size no less than one-half (1/2) inch in size, “GAS

VENT DIRECTLY BELOW. KEEP CLEAR OF ALL

OBSTRUCTIONS.”

4 - INSPECTION. The state or local gas inspector of the side wall, horizontally vented, gas-fueled equipment shall not approve the installation unless, upon inspection, the inspector observes carbon monoxide detectors and signage installed in accordance with the provisions of 248 CMR 5.08(2)(a) 1 through 4.

EXEMPTIONS: The following equipment is exempt from 24 CMR 5.08(2)(a) 1 through 4:

The equipment listed in Chapter 10 entitled

“Equipment Not Required to Be Vented” in the most current edition of NFPA 54 as adopted by the Board; and

2 - Product Approved side wall, horizontally vented, gasfueled equipment installed in a room or structure separate from the dwelling, building or structure used in whole or in part for residential purposes.

MANUFACTURER REQUIREMENTS - GAS EQUIP-

MENT VENTING SYSTEM PROVIDED.

When the manufacturer of Product Approved side wall, horizontally vented, gas-fueled equipment provides a venting system design or venting system components with the equipment, the instructions provided by the manufacturer for installation of the equipment and the venting system shall include:

1 - Detailed instructions for the installation of the venting system design or the venting system components: and

2 - A complete parts list for the venting system design or venting system.

MANUFACTURER REQUIREMENTS - GAS EQUIP-

MENT VENTING SYSTEM NOT PROVIDED.

When the manufacturer of Product Approved side wall, horizontally vented, gas-fueled equipment does not provide the parts for venting the flue gases, but identifies

“special venting systems,” the following requirements shall be satisfied by the manufacturer:

1 - The referenced “special venting system” instructions shall be included with the appliance or equipment installation instructions; and

2 - The “special venting systems” shall be Product

Approved by the Board, and the instructions for that system shall include a parts list and detailed installation instructions.

A copy of all installation instructions for all Product

Approved side wall, horizontally vented, gas-fueled equipment, all venting instructions, all parts lists for venting instructions, and/or all venting design instructions shall remain with the appliance or equipment at the completion of the installation.

Page 46

FOR THE PROVINCE OF ONTARIO, HORIZONTAL SIDE-

WALL VENT APPLICATIONS ONLY

For exterior horizontal venting applications, the 2” X 1.5” reducer for 2” venting at the point where the exhaust pipe exits the structure is not required in direct or non-direct vent applications in the Province of Ontario. In these applications, the vent should be oriented such that the exhaust plume is unobjectionable. If the installation requires more separation between the flue gases and the building struc ture, a reducer may be installed on the exhaust pipe to increase the flue gas velocity.

ADDENDUM FOR ALL PROVINCES OF CANADA

See below for venting in all provinces of Canada. Lennox approves the following termination for use in all provinces of Canada.

C

B

D

12”

A

A − Clearance above grade or average snow accumulation

2” (51MM)

Vent Pipe

3” (76MM)

Vent Pipe

12” (305 mm) Min. 12” (305 mm) Min.

B − Horizontal separation between intake and exhaust

6” (152 mm) Min.

24” (610 mm) Max.

6” (152 mm) Min.

24” (610 mm) Max.

C − Exhaust pipe length Per: Saskatchewan Code of Practice

D − Wall support distance from top of each pipe (intake/exhaust)

6” (152 mm) Max.

6” (152 mm) Max.

NOTE − Flue gas may be acidic and may adversely affect some building materials. If flue gases impinge on the building materials, a corrosion−resistant shield should be used to protect the wall surface. The shield should be constructed using wood, sheet metal or other suitable material. All seams, joints, cracks, etc. in affected area, should be sealed using an appropriate sealant.

Page 47

Blower Data

ML193DF045XE36B PERFORMANCE (Less Filter)

External

Static

Pressure in. w.g.

cfm

High

(Black)

Watts

Air Volume / Watts at Various Blower Speeds

Medium-High

(Brown)

Medium

(Blue)

Medium-Low

(Yellow) cfm Watts cfm Watts cfm Watts

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

1430

1395

1365

1330

1305

1275

1245

- - -

- - -

353

364

375

383

391

400

406

- - -

- - -

1305

1270

1245

1215

1180

1140

1110

1080

1030

270

279

291

298

310

320

328

335

332

1180

1145

1105

1070

1025

980

950

910

870

199

207

212

221

228

237

250

252

264

890

845

795

740

700

660

615

585

545

107

113

121

126

136

143

147

151

160

ML193DF070XE36B PERFORMANCE (Less Filter)

External

Static

Pressure in. w.g.

cfm

High

(Black)

Watts


Medium-High

(Brown)

Medium

(Blue)

Medium-Low


0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

1415

1380

1345

1325

1295

1260

1235

1185

- - -

340

351

360

371

380

392

402

411

- - -

1295

1265

1240

1215

1175

1135

1105

1080

1040

269

276

285

291

302

318

320

333

342

1175

1140

1090

1060

1025

985

955

910

865

191

202

208

218

228

236

247

254

261

905

860

810

770

710

670

620

585

540

101

109

119

124

132

138

146

152

157

ML193DF090XE48C PERFORMANCE (Less Filter)

External

Static

Pressure in. w.g.

cfm

High

(Black)

Watts


Medium-High

(Brown)

Medium

(Blue)

Medium-Low


0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

1720

1695

1680

1640

1605

1575

1550

1490

- - -

412

418

431

444

455

466

473

467

- - -

1530

1495

1445

1410

1385

1355

1310

1265

1240

281

288

300

309

318

325

334

346

354

1400

1365

1315

1285

1245

1215

1165

1125

1075

220

229

240

247

255

263

274

282

288

1290

1265

1240

1200

1160

1115

1085

1030

995

218

227

232

243

251

187

194

204

214

ML193DFE Model

-045

-070

-090

Red

Allowed

Not Allowed

TABLE 18

Allowable Heating Speeds

Yellow Blue

Factory Setting Allowed

Alllowed Factory Setting

Brown

Allowed

Model Number

All Models

Red

Factory Setting

TABLE 19

Allowable Circulation Speeds

Yellow Blue

Not Allowed Not Allowed

Brown

Not Allowed cfm

740

695

640

575

530

485

445

390

335

Low

(Red)

Watts

70

76

81

86

93

97

103

107

116 cfm

750

700

645

590

530

490

440

395

340

Low

(Red)

Watts

64

73

79

84

91

94

102

106

113 cfm

1195

1160

1110

1070

1020

975

925

885

825

Low

(Red)

Watts

171

179

188

195

202

146

152

159

165

Black

Not Allowed

Black

Not Allowed

Page 48

Lennox ML193DFE Gas Furnace Installation Instructions

INSTALLATION

INSTRUCTIONS

ML193DFE

THIS MANUAL MUST BE LEFT WITH THE

HOMEOWNER FOR FUTURE REFERENCE

Duct Installation

Down-Flow Unit

UNIT SET UP

(typical)

Line Voltage

Related manuals

Table of contents

Lennox ML193DFE Gas Furnace Installation Instructions

INSTALLATION

INSTRUCTIONS

ML193DFE

THIS MANUAL MUST BE LEFT WITH THE

HOMEOWNER FOR FUTURE REFERENCE

Duct Installation

Down-Flow Unit

UNIT SET UP

(typical)

Line Voltage

Related manuals

Lennox

ML193DFE Gas Furnace

Lennox

EL195UHNE Low Nox Series Units

Lennox

ML296DFV Series Units

Lennox

ML193UHE Gas Furnace

Lennox

ML196DFE Series Units

Lennox

ML195UH Series Units

Lennox

SL280DFNV Series Units

Lennox

SLP99DFV Series Units

Lennox

ML195DF Series Units

Lennox

Merit ML193UH

Lennox

ML296UHV Series Units

Lennox

ML196UHE Series Units

Table of contents