Independent Review · Updated June 2026

3 Ton 17 SEER 96% AFUE 100,000 BTU Goodman Gas Furnace and Air Conditioner System - Downflow

High-efficiency 3-ton combo system with 96% AFUE and 18 SEER1 at an accessible price point

8.2
IndustrialRank Score
Efficiency
8.5
Reliability
7.8
Value
8.0
Installation
8.5
Warranty
8.0
3 Ton 17 SEER 96% AFUE 100,000 BTU Goodman Gas Furnace and Air Conditioner System - Downflow
Current Price
$504
Check Price at HVACDirect → Shop Now at HVACDirect
Authorized dealer · Full manufacturer warranty
// Bottom Line
This Goodman system delivers excellent heating and cooling efficiency at $504, making it ideal for homeowners upgrading older equipment or contractors seeking a proven, budget-friendly combo unit. The 96% AFUE furnace and 18 SEER1 air conditioner balance performance with real-world affordability.

Review

The Goodman 3-ton downflow gas furnace and air conditioner system represents a practical middle ground in the residential HVAC market. Priced at $504, this combo unit targets homeowners and contractors seeking reliable equipment without premium pricing. Goodman maintains strong presence in contractor networks for good reason: their systems deliver consistent performance. This particular model emphasizes efficiency, carrying both Energy Star certification and respectable seasonal ratings that should appeal to cost-conscious buyers.

Performance specs tell an encouraging story. The furnace achieves 96% AFUE, meaning 96 cents of every heating dollar converts to home warmth, with 100,000 BTU capacity for adequate winter heating. Cooling delivers 18 SEER1 efficiency with a two-stage scroll compressor, variable-speed ECM blower motor, and plastic PVC exhaust compatibility. The unit operates at 71 dB, uses R410A refrigerant, and requires standard 115V single-phase 60Hz power with 21.3 to 35 amp breaker sizing. These specs align with modern efficiency standards.

Pros & Cons

Pros

  • 96% AFUE furnace efficiency minimizes heating fuel waste and reduces winter utility bills significantly
  • 18 SEER1 cooling rating exceeds Energy Star requirements for optimal air conditioning performance
  • Two-stage compressor and variable-speed ECM blower motor optimize comfort across partial and full load conditions
  • 100,000 BTU heating capacity handles cold climates with adequate sizing for most residential applications
  • 10-year warranty with online registration provides solid long-term protection at this price tier

Cons

  • Product listing shows conflicting tonnage data: title states 3 ton while specs list 3.5 ton, creating confusion
  • 35,000 cooling BTU appears undersized relative to the 3.5 ton rating, suggesting potential specification error
  • 71 dB noise level runs slightly loud during operation, noticeable in quieter neighborhoods or bedrooms

Who Should Buy

Best For

Homeowners replacing 15+ year old furnace and AC units who prioritize efficiency savings over premium features, or budget-conscious contractors needing dependable residential combo systems for modest-sized homes in moderate to cold climates.

Consider Alternatives If

Anyone requiring a true 3-ton system should verify actual cooling capacity, and buyers in noise-sensitive environments may prefer units rated below 70 dB.

3 Ton 17 SEER 96% AFUE 100,000 BTU Goodman Gas Fur
$504
Buy at HVACDirect →

Installation

This downflow A-coil configuration suits attic or basement installations where gravity-assisted airflow works naturally. Copper line sets feature 3/8 inch liquid and 7/8 inch suction ports with 3/4 inch insulation thickness and 50-foot maximum length. Standard sweat valve connections require basic soldering skills or professional service. Electrical installation demands only standard 120V power. Most contractors complete installation in one day with proper staging.

Warranty & Reliability

Online registration unlocks a 10-year parts and compressor warranty, placing this system in the solid mid-tier protection category. Coverage extends through typical system lifespan for residential use. Registration is straightforward and necessary to activate benefits. This warranty assumes proper installation and maintenance per Goodman specifications.

Specifications

SKULS38783850
Brand/ManufacturerOnline Supply
Cooling BTU35,000
Heating BTU100,000
RefrigerantR410A
Electrical115 V. 1 Phase 60 Hz
Warranty10 Years with Online Registration
Decibel Level (dBA)71
Weight (in lbs)30.000000
FeatureSpec
Product FeaturesRebate Available
Energy StarYes
SEER1 (Efficiency)18
Condenser StagesTwo Stage
Compressor TypeScroll
Liquid Valve Size3/8"
Suction Valve Size3/4"
Max Breaker Size35 amps
Min. Breaker Size21.3 amps
Tonnage3.5 Ton
Valve TypeSweat
Height34.5"
Width21"
Depth28.75"
ResourcesGoodman Brochure Goodman Installation Instructions Goodman Parts Manual Goodman Service Manual Goodman Specifications Goodman Technical Information Goodman User Information Goodman 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.
ConfigurationDownflow/Horizontal
Liquid Line3/8"
Suction Line7/8"
StyleA-Coil
AHRI Certificate Number7368844
Airflow DirectionDownflow/Horizontal
Exhaust Flue RequirementPlastic / PVC
Furnace Efficiency / AFUE96%
Blower MotorVariable Speed - ECM
Maximum CFM2000
Burner StagesTwo
Fuel TypePropane, Natural Gas
Suction Line Insulation Thickness3/4"
Length50 feet

Frequently Asked Questions

What's the actual tonnage, 3 or 3.5 tons? +
Specifications list 3.5 ton capacity, though the product title says 3 ton. This discrepancy warrants clarification with the seller before purchase. If true cooling output is 35,000 BTU as listed, the system undershoots even 3-ton standards (36,000 BTU). Request a confirmed AHRI certificate matching your intended application.
Can I install this myself? +
Furnace and electrical portions can be handled by experienced DIYers with proper permits. However, refrigerant charging absolutely requires EPA-certified technicians. Improper charging causes efficiency loss and compressor damage. Budget for professional installation unless you hold current EPA Section 608 certification.
How much will this save on heating and cooling bills? +
The 96% AFUE furnace reduces heating costs roughly 15-25% compared to 80% AFUE units, depending on climate and usage. 18 SEER1 cooling saves approximately 20-30% versus older 10 SEER equipment. Actual savings depend on local energy rates, home insulation quality, and thermostat programming habits.
How does this compare to Carrier or Lennox equipment? +
Goodman delivers comparable efficiency and reliability at significantly lower cost than Carrier or Lennox premium lines. You sacrifice brand prestige and extended warranty options for solid mid-range performance. Goodman parts availability rivals major competitors through most contractors and online suppliers.
Is the 10-year warranty worth it? +
Yes. Most furnace and compressor failures occur within the first decade. Online registration takes minutes and provides meaningful peace of mind. This warranty represents good value at this price point, though exclude coverage for installation errors or lack of maintenance.

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