Trane A951X120DD5SA Gas Furnace 120000 Btu/h 95% Afue Multi Speed Downflow

Product Description

The Trane A951X120DD5SA is a single-stage, multi-speed natural gas furnace designed for dedicated downflow installations in residential forced-air heating systems. It delivers 120,000 BTU/h of heating input at 95% AFUE, meaning the unit converts 95 cents of every fuel dollar into usable heat. The furnace operates on 24-volt low-voltage control wiring and features a 9-tap Constant Torque Motor (CTM) with a nominal airflow of 2,000 CFM. Cabinet dimensions are 24.5 inches wide, 28.75 inches deep, and 34 inches tall. This unit is part of the RunTru by Trane RT Series, positioned as a reliable, cost-effective heating solution for residential applications. Licensed HVAC technicians are the intended installers.

The A951X120DD5SA is configured exclusively for downflow airflow orientation, making it suited for installations where supply air discharges downward through a floor or plenum below the unit. Typical scenarios include utility closet installs, garage mechanical rooms, and crawlspace-adjacent applications where downflow discharge is required. It integrates into standard forced-air duct systems and is compatible with split-system cooling when paired with a matched coil and outdoor unit. Compatible system pairings noted in supplier data include the A5AC3048A1 air conditioner and the 5MXCD010AC6HCA coil, among others.

Key Features

• 120,000 BTU/h heating input with 95% AFUE efficiency rating
• Single-stage gas valve with multi-speed CTM blower motor for variable airflow
• 9-tap CTM motor connector allows airflow balancing across a wide range of duct configurations
• Dedicated downflow cabinet orientation at 24.5 inches wide fits standard alcove and closet installations
• 24-volt low-voltage control interface compatible with standard thermostat wiring
• Nominal 2,000 CFM airflow capacity supports larger residential duct systems

Compatibility

Supplier data identifies this furnace as compatible with the A5AC3048A1 air conditioner and the 5MXCD010AC6HCA coil as part of a matched split system. It is designed as a downflow-only replacement or new-install furnace for residential gas heating applications requiring a 24.5-inch cabinet width.

Installation Notes

Installation must be performed by a licensed HVAC technician in accordance with local mechanical codes, the current edition of the IFGC, and the manufacturer installer guide (document 88-A951X001-1D-EN). Shut off all gas supply and disconnect electrical power at the disconnect switch before beginning any service or installation work. Verify flue venting meets local code requirements for 95% AFUE Category IV appliances before final commissioning. Do not alter gas orifices, burner assemblies, or CTM motor tap wiring without referencing the manufacturer installation documentation.

Technical Specifications

• Heating Input Capacity: 120,000 BTU/h
• AFUE: 95%
• Staging: Single stage
• Blower Motor Type: Multi-speed Constant Torque Motor (CTM)
• Motor Taps: 9-tap
• Nominal Airflow: 2,000 CFM
• Control Voltage: 24 volts
• Airflow Orientation: Dedicated downflow
• Cabinet Width: 24.5 inches
• Cabinet Depth: 28.75 inches
• Cabinet Height: 34 inches
• Series: RunTru RT Series

Standard Information

• Brand: Trane
• Manufacturer Part Number: A951X120DD5SA