Lennox International Inc Merit Series Gas Furnace installation instructions Right, End Bottom

Page 11

Removing the Bottom Panel

Remove the two screws that secure the bottom cap to the furnace. Pivot the bottom cap down to release the bottom panel. Once the bottom panel has been removed, reinstall the bottom cap. See figure 11.

Removing the Bottom Panel

Screw

Bottom Cap

Bottom Panel

 

FIGURE 11

 

 

Horizontal Application

 

 

Installation Clearances

 

 

Top

 

Left

FLOW

Right

AIR

End

 

End

 

Bottom

 

Vent Connector

Type C

Type B1

Type

 

 

Top

0

0

*Front

2−1/4 in. (57 mm)**

2−1/4 in. (57 mm)

 

 

 

Back

0

0

 

 

 

Ends

2 in. (51 mm)

2 in. (51 mm)

 

 

 

Vent

6 in. (152 mm)

1 in. (25 mm)

 

 

 

Floor

0‡

0‡

*Front clearance in alcove installation must be 24 in. (610 mm). Maintain a minimum of 24 in. (610 mm) for front service access. ** 4−1/2 in. if singlewall vent pipe is used.

‡For installations on a combustible floor, do not install the furnace directly on carpeting, tile or other combustible materials other than wood flooring.

FIGURE 12

Horizontal Applications

The ML180UH furnace can be installed in horizontal ap- plications. Order horizontal suspension kit (51W10) from Lennox, or use equivalent suspension method.

Allow for clearances to combustible materials as indicated on the unit nameplate. Minimum clearances for closet or al- cove installations are shown in figure 12.

This furnace may be installed in either an attic or a crawl- space. Either suspend the furnace from roof rafters or floor joists, as shown in figure 13, or install the furnace on a platform, as shown in figure 14.

Typical Horizontal Application

 

Unit Suspended in Attic or Crawlspace

 

 

Metal

Internal

Strap

Brace

 

Bracket

3/16

 

Air Flow

FIGURE 13

NOTE − Heavy−gauge perforated sheet metal straps may be used to suspend the unit from roof rafters or ceiling joists. When straps are used to suspend the unit in this way, support must be provided for both the ends. The straps must not interfere with the plenum or exhaust pip- ing installation. Cooling coils and supply and return air plenums must be supported separately.

NOTE − When the furnace is installed on a platform in a crawlspace, it must be elevated enough to avoid water damage and to allow the evaporator coil to drain.

Return Air −− Horizontal Applications

Return air must be brought in through the end of a furnace installed in a horizontal application. The furnace is equipped with a removable bottom panel to facilitate installation. See figure 11.

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Contents Table of Contents Installation Instructions ML180UHTOP View Unit Dimensions − inches mmParts Arrangement Shipping and Packing List Safety InformationML180UH Gas Furnace General Use of Furnace as Construction HeaterCombustion, Dilution & Ventilation Air Equipment in Confined Space ALL AIR from Inside Equipment in Confined Space Setting Equipment Return Air Plenum End Bottom Horizontal Application Installation Clearances Top LeftRight Duct System FiltersLeft Side Vent Discharge VentingUpflow Position Top Vent DischargeSide Vent Discharge Horizontal Left PositionHorizontal Right Position Vent Connection Upflow and Horizontal Position Common Venting Using Metal−Lined Masonry Chimney −1/2 18 − The common vent diameter must always be at least as Cated or common venting system, you must inspectFeet FAN + FAN FAN + NAT 112 175 169 278 Carbon Monoxide Poisoning Hazard Every 8 to 10 feet 2.44 to 3.01 m with suitable hang Ers or straps. Install a drip leg in vertical pipe runs to− In some localities, codes may require the installation Gas PipingRight−Side Air Discharge Horizontal ApplicationLeft−Side Air Discharge Electrostatic Discharge ESD Interior MAKE−UP BOX InstallationElectrical Thermostat Designations ML180UH Schematic Wiring Diagram and Sequence of Operation Integrated Control Typical ML180UH Field Wiring DiagramUnit Start−Up For Your Safety Read Before LightingHigh Altitude Gas Pressure AdjustmentProper Combustion Manifold Pressure Settings at all Altitudes Other Unit AdjustmentsNo Jumper Heat FAN-OFF Time in Seconds885 453 900750 680653 Single Side Return Air − Air volumes in bold require field1391 860Electrical SHOCK, Fire Or Explosion Hazard Service−045 and −070 units ML180UH BURNER, Combustion AIR Inducer AssemblyHeat Exchanger Removal −090, −110 −135 unitsPage Repair Parts List Planned ServiceDescription Integrated Control Diagnostic CodesNormal Heating Mode Abnormal Heating Mode Troubleshooting Heating Sequence of OperationHeating Sequence Normal Cooling Mode Abnormal Cooling Mode Troubleshooting Cooling Sequence of OperationContinuous Heat Speed FAN Sequence of Operation Troubleshooting Continuous Fan Sequence of Operation

Merit Series Gas Furnace specifications

Lennox International Inc. is a leading name in the heating and cooling industry, and their Merit Series Gas Furnace embodies the commitment to quality and efficiency that the company is known for. The Merit Series is designed to provide reliable heating in a sustainable manner, making it an excellent choice for homeowners seeking comfort without excessive energy bills.

One of the standout features of the Merit Series Gas Furnace is its efficiency ratings. The units in this series typically boast Annual Fuel Utilization Efficiency (AFUE) ratings of up to 95%. This level of efficiency means that the furnace converts a significant portion of the fuel it uses into heat, ultimately lowering operating costs. Such energy-efficient performance is not only beneficial for the wallet but also promotes environmental sustainability.

The Merit Series also incorporates advanced technologies that enhance its operation. The inclusion of a multi-speed blower motor is a notable feature that provides thoughtful airflow management throughout the home. By adjusting the speed according to the heating needs, the furnace optimizes comfort levels while minimizing noise and energy consumption. Homeowners can enjoy a warm environment without the disruptive sounds often associated with traditional furnaces.

Moreover, the Merit Series comes equipped with durable construction materials designed to withstand the test of time. From the robust heat exchanger to the heavy-gauge cabinet, Lennox focuses on longevity and reliability. This ensures that homeowners can trust their furnace to operate effectively even in the harshest winter conditions.

Safety features are also integral to the design of the Merit Series Gas Furnace. With an integrated Flame Sensor and a built-in safety shut-off system, the furnace ensures that any irregularities in operation are promptly detected and addressed. Such measures provide peace of mind for families using the heating system throughout the cold months.

Installation and maintenance are further simplified with the Merit Series. Its design facilitates easier access for HVAC professionals, allowing for quicker installations and routine service, ensuring that homeowners spend less time and money on upkeep.

In conclusion, Lennox International Inc.'s Merit Series Gas Furnace combines efficiency, advanced technology, and robust construction, making it a top choice for families looking to enhance their home's heating system. With its energy-saving innovations and commitment to reliability, the Merit Series stands as an exemplary option in today’s market.
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