EcoTemp 95% Single Stage 80K BTU Gas Furnace, WFSX080B048B
When winters get colder or the floor plan gets bigger, the EcoTemp WFSX080B048B adds real heating muscle without growing the footprint. This 80,000 BTU input, 78,000 BTU output condensing gas furnace keeps the same 17-1/2" cabinet as the 60K model while reaching 97.0% AFUE in upflow and horizontal positions. Four burners, a stainless steel secondary heat exchanger, and a 3/4 HP multi-speed constant torque ECM blower make it a strong fit for larger homes, colder-climate replacements, and contractors who want one cabinet size to stock for several jobs. Explore more EcoTemp furnaces and split systems.
Is an 80,000 BTU Gas Furnace the Right Size?
An 80K furnace belongs in homes whose calculated heat loss lands between the 60K and 100K outputs, usually larger single-family houses, older homes with less insulation, or any home in a region with a low winter design temperature. EcoTemp's instructions are clear that the WFSX should be sized to the design heating load using ACCA Manual J and S or another approved method, not to the size of the furnace being removed.
If you are replacing an older standard-efficiency furnace, do not assume the same input rating is needed. Because a 97% AFUE furnace turns more of its input into delivered heat, the WFSX080B048B's 78,000 BTUh output may cover a load that once called for a bigger 80% unit. Air sealing, attic insulation upgrades, replacement windows, duct condition, and installation altitude should all be considered before you select a size.
Ideal for: Larger two-story homes, colder-climate furnace replacements, homes upgrading from older 80%–90% furnaces, and systems paired with up to roughly a 4-ton air conditioner.
Need more capacity? Step up to the EcoTemp 95% Single Stage 100K BTU Gas Furnace, WFSX100C060B for higher heat loads and a 2,000 CFM cooling designation.
Recommended heating applications are general guidelines only. Actual furnace sizing depends on a heat-load calculation, insulation, climate, ductwork, elevation, and air-conditioning match. Request free sizing assistance, contact Budget Heating, or call 813-885-7999.
What's Included
| Gas Furnace | WFSX080B048B — 80,000 BTU Single-Stage Condensing Gas Furnace |
|---|---|
| Heating Input / Output | 80,000 BTUh Input / 78,000 BTUh Output |
| Efficiency | 97.0% AFUE Upflow/Horizontal, 95.0% AFUE Downflow |
| Fuel | Natural Gas (Propane with Factory Conversion Kit) |
| Blower Motor | 3/4 HP Multi 18-Speed Constant Torque ECM |
| Airflow Positions | Multi-Position: Upflow, Downflow, Horizontal Left/Right |
| Electrical | 115V, Single Phase, 60 Hz — 15 Amp Max Breaker |
| Cabinet Width | 17-1/2" W x 35" H |
Inside the WFSX080B048B you get four inshot burners, a redundant White-Rodgers gas valve, a silicon nitride igniter, and an 11" x 8" direct-drive blower wheel driven by a 3/4 HP ECM motor. The factory default heating tap (#12) delivers 1,290 CFM at rated static, and cooling airflow is adjustable from 370 to 1,625 CFM. Shipping weight is 150 lb. Vent pipe, condensate drain components, return filter, and thermostat are field supplied.
Furnace Performance & Installation Features
WFSX080B048B Heating & Efficiency
- 78,000 BTUh heating output in a 17-1/2" cabinet
- 97.0% AFUE upflow/horizontal, 95.0% AFUE downflow
- ENERGY STAR version 5.0 North qualified in upflow/horizontal
- Four-burner single-stage heating with silicon nitride ignition
- 1,290 CFM heating airflow at the default setting
- 40–70°F certified temperature rise for even, comfortable heat
- Stainless steel secondary heat exchanger
- Insulated heat exchanger compartment
- Manual-reset flame roll-out switches and main limit control
- Suitable for 40 ng/J NOx air quality districts
WFSX080B048B Installation & Service
- Same 17-1/2" footprint as the 60K WFSX for easy cabinet swaps
- Four installation positions for basements, closets, attics, crawlspaces
- Vent with 1-1/2" through 4" pipe based on length and altitude
- Up to 175 ft. equivalent vent length on 3" pipe (0–2,000 ft.)
- Through-the-casing flue option for downflow or horizontal (accessory)
- Cooling airflow adjustable from 370 to 1,625 CFM
- Electronic air cleaner (EAC-1) and humidifier (HUM) terminals
- Approved for twinning with manufacturer's accessory kit
- 3-digit display speeds up fault diagnosis
- 14 AWG minimum wire on a 15 amp breaker
Specifications & Manuals
Use the 80,000 BTUH vent tables in the technical specifications to choose pipe diameter, and see the installation instructions for condensate trap setup in each position. Find ventilation pipe and accessories, 3.5–4 ton cased evaporator coils, and furnace air filters.
Frequently Asked Questions
Should I choose the 80K or the 60K WFSX if both use a 17-1/2" cabinet?
Pick based on your heat-loss calculation. The WFSX080B048B delivers 78,000 BTUh versus 58,000 BTUh for the WFSX060B048B, and its heating airflow is higher (1,290 vs. 1,030 CFM). Both share the same cabinet width and 1,600 CFM cooling designation, so ductwork connections are similar.
What is the actual heating output of the WFSX080B048B?
The DOE-rated output capacity is 78,000 BTUh from 80,000 BTUh of input, certified for elevations up to 2,000 ft. Above that, U.S. installations reduce ratings 4 percent per 1,000 ft.
Which thermostat wires does the WFSX080B048B accept?
The control board uses standard G, C, W, Y, and R connections for single-stage heating and single-stage cooling. There is no communicating system, so any compatible 24V conventional thermostat works.
Can the WFSX080B048B be installed in a manufactured home?
Yes, when the manufacturer-approved manufactured (mobile) home accessory kit is installed, ordered separately. The furnace is not designed for recreational vehicles or outdoor installation.
What vent pipe diameter works for long runs on the WFSX080B048B?
At 0–2,000 ft. elevation the 80K allows 55 ft. on 2" pipe, 130 ft. on 2-1/2", 175 ft. on 3", and 200 ft. on 4" pipe (maximum equivalent vent length before elbow deductions). Use the smallest diameter that meets your run, as oversizing can cause icing or flame disturbance.
What is the default heating airflow setting on the WFSX080B048B?
Airflow setting #12 is the factory heating default, with a designated heating range of settings 7–13. Cooling defaults to setting #18 and constant fan to setting #1, all adjustable to achieve the proper temperature rise.
WFSX Technical Specifications
ICP Warranty Certificate
