Independent Review · Updated June 2026

3.5 Ton 16 SEER 96% AFUE 120,000 BTU Goodman Gas Furnace and Air Conditioner System - Horizontal

High-efficiency horizontal furnace with 16 SEER cooling and 96% AFUE heating

8.2
IndustrialRank Score
Efficiency
8.5
Reliability
7.8
Value
8.0
Installation
8.5
Warranty
8.0
3.5 Ton 16 SEER 96% AFUE 120,000 BTU Goodman Gas Furnace and Air Conditioner System - Horizontal
Current Price
$0
Check Price at HVACDirect → Shop Now at HVACDirect
Authorized dealer · Full manufacturer warranty
// Bottom Line
This Goodman system works best for homeowners upgrading attic or basement installations where horizontal orientation is required. The 96% AFUE furnace and 16 SEER air conditioner deliver strong efficiency gains, and the dual-fuel capability covers both natural gas and propane applications.

Review

The Goodman 3.5-ton horizontal system combines a gas furnace and air conditioning unit in one integrated package, targeting mid-range residential applications. Online Supply positions this as a value-oriented option for homeowners replacing older equipment or upgrading existing horizontal installations. The system's dual-fuel compatibility and plastic flue option appeal to contractors managing diverse installation scenarios across mixed climates.

Performance numbers tell a compelling efficiency story. The furnace delivers 120,000 BTU heating output at 96% AFUE, meaning 96 cents of every fuel dollar convert to usable heat. The cooling side produces 42,000 BTU (3.5 tons) with 16 SEER rating, translating to roughly 16 units of cooling per watt consumed. Variable-speed ECM blower supports up to 2000 CFM, allowing the system to match load demands rather than cycling at full capacity constantly.

Pros & Cons

Pros

  • 96% AFUE furnace efficiency reduces heating costs significantly compared to older 80% units
  • 16 SEER cooling efficiency qualifies for Energy Star and many utility rebates
  • Variable-speed ECM blower motor optimizes airflow and reduces runtime noise
  • Dual fuel capability handles both natural gas and propane without modifications
  • Plastic/PVC exhaust flue reduces installation complexity and material costs
  • Two-stage burner provides better temperature control and shorter runtimes

Cons

  • Single-stage condenser limits cooling modulation compared to two-stage units
  • 73 dBA noise level at full capacity is audible in quiet homes
  • Tonnage mismatch: 5-ton condenser paired with 3.5-ton rating suggests sizing confusion in specs

Who Should Buy

Best For

Homeowners with horizontal ductwork in attics or crawl spaces who need both heating and cooling upgrades. This system is ideal for those seeking Energy Star certification and utility rebates without premium pricing.

Consider Alternatives If

Anyone with existing upflow equipment should verify compatibility, and buyers in areas with extremely cold winters may want to compare with higher-stage heating options.

3.5 Ton 16 SEER 96% AFUE 120,000 BTU Goodman Gas F
$0
Buy at HVACDirect →

Installation

Horizontal orientation requires proper return ductwork configuration and support mounting. The 48-pound unit fits compact spaces with dimensions of 26 inches wide by 24.5 inches tall by 21.125 inches deep. Plastic PVC exhaust venting simplifies installation compared to metal flue requirements. Dual voltage options (208/230V single phase) accommodate most residential electrical panels, requiring 23.5 to 40-amp breakers depending on final configuration.

Warranty & Reliability

Goodman provides 10 years of parts and labor coverage upon online registration. This duration is standard for mid-tier equipment and covers compressor, heat exchanger, and coil defects. Registration is essential, as some manufacturers reduce unregistered coverage to 5 years. Extended warranties are typically available through distributors for additional protection beyond the base coverage period.

Specifications

SKULS381183850
Brand/ManufacturerOnline Supply
Cooling BTU42,000
Heating BTU120,000
RefrigerantR410A
Electrical208 / 230 V. 1 Phase 60 Hz
Warranty10 Years with Online Registration
Decibel Level (dBA)73
Weight (in lbs)48.000000
FeatureSpec
AHRI Certificate Number7368842
Airflow DirectionUpflow/Horizontal
Exhaust Flue RequirementPlastic / PVC
Product FeaturesRebate Available
Furnace Efficiency / AFUE96%
Blower MotorVariable Speed - ECM
Maximum CFM2000
ConfigurationHorizontal
Energy StarYes
Burner StagesTwo
Fuel TypePropane, Natural Gas
Height24.5"
Width26"
Depth21.125"
ResourcesCHPF Installation Manual CHPF Specifications Sheet Goodman Evaporator Coil Warranty You will need Adobe® Acrobat® Reader to view PDF documents.
Safety InformationPROPOSITION 65 WARNING This product and many products on our site may contain a chemical know to the state of California to cause cancer or birth defects or other reproductive harm. For more information about Proposition 65 please Click Here.
SEER1 (Efficiency)16
Condenser StagesSingle Stage
Compressor TypeScroll
Liquid Valve Size3/8"
Suction Valve Size7/8"
Max Breaker Size40 amps
Min. Breaker Size23.5 amps
Tonnage5 Ton
Liquid Line3/8"
Suction Line1 1/8"
StyleA-Coil
Suction Line Insulation Thickness1/2"
Length50 feet

Frequently Asked Questions

Why does the spec show 5-ton tonnage when the product is listed as 3.5-ton? +
This appears to be a specification inconsistency. The cooling capacity is definitively 42,000 BTU, which equals exactly 3.5 tons (12,000 BTU per ton). The 5-ton reference may indicate condenser design, but the cooling output remains 3.5-ton rated. Clarify with Online Supply before ordering.
Can I install this in an upflow position instead of horizontal? +
The unit is specifically designed for horizontal installation in attics or crawl spaces. Upflow installation risks improper heat exchanger operation and condensation management. Check CHPF Installation Manual specifications, but upflow conversion is not recommended without manufacturer guidance.
How much will this reduce my heating and cooling bills? +
Energy savings depend on your current equipment efficiency. Upgrading from an 80% AFUE furnace and 10 SEER air conditioner to this 96% AFUE and 16 SEER system typically saves 15-25% annually on heating and cooling costs, though regional climate and usage patterns significantly affect actual savings.
Is 16 SEER still competitive in 2024? +
16 SEER meets Energy Star standards and qualifies for most utility rebates, though some manufacturers now offer 18+ SEER models. At the $0 price point listed, this represents solid value. However, verify current SEER2 ratings, as EPA transitioned labeling standards in 2023.
What happens if I don't register the warranty? +
Most manufacturers reduce unregistered warranty from 10 years to 5 years. Online registration is simple, typically takes minutes on Goodman's website, and protects your investment. Don't skip this step after installation.

Affiliate disclosure: IndustrialRank earns a commission on qualifying purchases at no extra cost to you. We only recommend products we have independently reviewed.