Rheem Select 100,000 BTU 80% AFUE Gas Furnace

W801T1005A21UHSNAS Rheem 100,000 BTU Gas Furnace

W801T1005A21UHSNAS is a Rheem Select residential gas furnace designed to deliver dependable heating and flexible indoor airflow. It provides 100,000 BTU per hour of heating input, approximately 80,000 BTU per hour of heating output and 80% AFUE performance. Its single-stage heating system and five-speed constant-torque blower make it suitable for compatible residential split HVAC systems.

The furnace supports upflow or horizontal installation and uses a low-profile cabinet approximately 34 inches high. It can be paired with an approved evaporator coil and outdoor air conditioner to create a complete gas split system. All components must be properly sized and matched before installation.

100,000 BTU Heating Input

The W801T1005A21UHSNAS has a rated natural-gas heating input of 100,000 BTU per hour. With its 80% AFUE rating, the furnace provides approximately 80,000 BTU per hour of usable heating output under standard test conditions.

AFUE represents the percentage of fuel energy converted into useful seasonal heat. An 80% AFUE furnace delivers approximately 80% of the fuel’s energy to the conditioned space, while the remaining portion leaves through the venting system.

The correct furnace capacity must be determined through a professional heating-load calculation. Climate, insulation, windows, air leakage, ceiling height, ductwork and building construction all affect the required heating output. A 100,000 BTU furnace should not be selected using square footage alone.

Single-Stage Heating Operation

The W801T1005A21UHSNAS uses single-stage gas heating. When the thermostat calls for heat, the furnace operates at its available heating capacity until the indoor temperature reaches the selected setting.

This straightforward design provides familiar operation and service requirements. Correct sizing is especially important because an oversized single-stage furnace may cycle frequently, while an undersized furnace may struggle to maintain comfort during cold weather.

Five-Speed Constant-Torque Blower

The W801T1005A21UHSNAS includes a five-speed constant-torque ECM blower motor. Multiple airflow settings allow the installer to coordinate the furnace with the selected evaporator coil and outdoor air-conditioning equipment.

This model uses a nominal 5 ton blower drive and provides approximately 1,840 CFM at its published cooling rating point. The final airflow depends on the selected speed tap, duct static pressure, evaporator coil and system configuration.

The 5 ton designation refers to the blower’s maximum nominal cooling support. It does not describe the furnace’s heating capacity. Heating performance is determined by its 100,000 BTU input and approximately 80,000 BTU output.

Upflow or Horizontal Configuration

The W801T1005A21UHSNAS is approved for upflow or horizontal installation. In an upflow application, return air enters through the lower portion of the furnace and conditioned air exits through the top. In a horizontal application, the furnace is installed on its side in an approved orientation.

The furnace must not be installed on its back with the access doors facing upward. Installation orientation, combustion clearances, venting and service access must follow Rheem’s instructions and applicable codes.

This furnace is not approved or recommended for manufactured or mobile homes. It is intended for compatible residential site-built applications. A furnace specifically certified for manufactured housing must be used in mobile-home installations.

Direct Spark Ignition and Diagnostics

A direct spark ignition system lights the burners electronically when heating is requested. This eliminates the need for a continuously burning standing pilot and supports reliable furnace operation.

The integrated seven-segment diagnostic display gives qualified technicians clearer operating and fault information during setup or service. The blower compartment also includes a door safety switch that interrupts operation when the access panel is removed.

Durable Heat Exchanger and Cabinet

The furnace uses an aluminized-steel heat exchanger designed to resist corrosion and repeated thermal cycling. Its removable heat-exchanger configuration supports service access, while hemmed cabinet and door edges help improve handling during maintenance.

The W801T1005A21UHSNAS has a low-profile cabinet approximately 34 inches high and a nominal width of approximately 21.5 inches. Xpress Supply lists approximate overall dimensions of 26 inches deep, 21 inches wide and 34 inches high, with a weight of approximately 140 pounds.

Actual installation clearances are not the same as cabinet dimensions. The contractor must provide the required space around the furnace for combustion air, venting, duct connections, filters and future maintenance.

Electrical, Gas and Venting Requirements

This furnace operates on a 115-volt, single-phase, 60 Hz electrical supply. The manufacturer lists a minimum circuit ampacity of approximately 10 amps and 15-amp overcurrent protection for this model.

The gas connection is 1/2-inch NPT. Factory configuration and approved fuel type must be confirmed before installation. Any conversion to propane requires the correct manufacturer-approved conversion kit, adjustments and professional testing.

As an 80% AFUE furnace, the unit requires code-compliant combustion venting. Vent material, diameter, termination, combustion air and clearances must follow the National Fuel Gas Code, local regulations and Rheem’s installation instructions.

Compatible Cooling Equipment Required

The W801T1005A21UHSNAS is the gas furnace only. It does not include an outdoor condenser, evaporator coil, thermostat, refrigerant line set, filter cabinet, venting materials or installation accessories unless those items are specifically included in a package.

For central air conditioning, the furnace must be paired with a compatible evaporator coil and outdoor condenser. The coil width, refrigerant type, blower airflow and certified equipment match must be confirmed before ordering.

Professional Installation Required

The W801T1005A21UHSNAS must be installed and commissioned by a qualified HVAC professional. Installation includes gas-pressure adjustment, combustion testing, venting, electrical wiring, airflow setup, temperature-rise verification and safety-control testing.

This standard-NOx model may not satisfy emissions requirements in certain regulated air districts. Local furnace efficiency, emissions and installation rules should be verified before purchase.

Review the official Rheem W801T specification sheet and browse more HVAC equipment from Xpress Supply. Confirm the fuel type, heating load, cabinet width, installation orientation and complete equipment match with your contractor.