Two-Stage Variable Speed Furnaces - 96% AFUE

Higher-efficiency heating with higher savings.

Durastar’s Advanced Series two-stage variable-speed furnaces – 96% AFUE have additional technologies that elevate system efficiencies and deliver premium energy savings. AFUE, or Annual Fuel Utilization Efficiency, is a standard measurement that represents how effective your furnace is at turning fuel into heat. This high energy rating is a result of the system’s dual-stage power output. Aluminized primary and stainless steel secondary heat exchangers work together and adjust their output based on the current demands of the environment, drawing the minimal power necessary to maintain the desired temperature throughout your home. For example, during extreme cold weather events, the two-stage variable-speed furnaces operate using 100% power. However, on most days, they operate with a minimal output of 60-65% to reduce power usage. Furthermore, variable speed motors quiet the airflow and control humidity, creating a relaxing home environment. Depend on Durastar for heating and cooling solutions that are tested to perform and built to last.




No one stands behind their brand like we do. Durastar offers durable airflow during even the harshest heating and cooling conditions. In addition, our warranty provides maximum coverage for total peace of mind.

Extended warranty options are available for both parts and labor. Talk to your contractor for more information.

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Two-Stage Variable Speed Furnaces - 96% AFUE Features

  • HVAC equipment products sold to licensed contractors only. Products sold in select areas only, please contact your local branch for availability in your area.
  • Not all Durastar products may be available in all areas currently. See your local Durastar distributor for details.
  • Two-Stage Heating: Furnace operation mainly stays at low capacity around 60-65%, but will switch to high capacity to deliver stable heat distribution
  • Bluetooth Connectivity for ease of monitoring, troubleshooting, and repairing the product
  • Direct spark ignition system is one of the most dependable ignition systems on the market
  • Blocked drain sensor will prevent water spillage and potential water damage to your home.
  • Low profile 34" cabinet is ideal for space constrained installations
  • Aluminized steel constructed heat exchanger provides maximum corrosion resistance and thermal fatigue reliability. It is also removable for improved serviceability


  • AFUE: 96.00 %
  • BTU: 40000
  • BTU Heat Rating: 41000 Btu/h
  • Blower Type: Direct Drive
  • Communicating: Non-Communicating
  • Condensing: Yes
  • Configuration: Multi
  • Energy Star Compliant: Yes
  • Fan Speeds: Variable
  • Flue Size: 4
  • Fuel Type: Natural Gas
  • Green Product: Yes,Energy Star
  • Height: 34 in
  • Horsepower: 1/2 hp
  • Ignition System: Direct Spark Ignition
  • Length: 28 in
  • MBH: 40
  • Phase: Single Phase
  • Power Source: Gas
  • Specifications - UL Listed: Yes
  • Stages: Two
  • Style Name: DR96M4AW
  • Tonnage: 3 Ton
  • Volts: 115V
  • Weight: 123.5 lb
  • Width: 17-1/2 in

DR96M4AW0402317SAB Documents

Frequently Asked questions

Is an air handler or furnace better?

Both Durastar’s furnaces and air handlers offer dependable options for distributing even airflow throughout your home. When selecting between the two, consider your location and climate. For areas with long warm seasons, an air handler will likely be more energy-efficient, however, we recommend discussing your options with a licensed contractor to ensure the best combinations of HVAC products for your home.

What does variable speed mean?

Variable speed air handlers operate at the lowest possible speed to achieve your desired indoor temperature. This results in increased energy efficiency. Variable speed units are also quieter than standard units.

Is a two-stage air handler more efficient than a single-stage air handler?

Yes, when paired with a two-stage outdoor unit, both units will operate on low capacity during milder days, requiring less energy; and switch to full capacity and power when needed.

What is AFUE?

Annual Fuel Utilization Efficiency (AFUE), is a standardized measure of efficiency for how furnaces and boilers convert energy to useable heat.

What is the main difference between a furnace and a heat pump?

Furnaces burn fuel to generate heat whereas a heat pump draws air from outdoors across the condenser coil, either releasing heat to the outdoor air when in cooling mode or absorbing heat from the outdoors, even in the coldest weather in heating mode.

How often should my furnace be serviced?

Durastar recommends your furnace to be serviced at least once a year to ensure it is functioning optimally and providing maximum comfort.

How to talk to your contractor

Learn how to talk the talk with a few of our top tips. We cover important questions to ask your HVAC contractor, common mistakes when buying a new system, and more.

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