Independent Review · Updated June 2026

3 Ton 18 SEER 80% AFUE 80,000 BTU Goodman Gas Furnace and Air Conditioner System - Upflow

18 SEER efficiency and 80% AFUE heating in one affordable package

8.2
IndustrialRank Score
Efficiency
8.5
Reliability
7.8
Value
8.0
Installation
8.5
Warranty
8.0
3 Ton 18 SEER 80% AFUE 80,000 BTU Goodman Gas Furnace and Air Conditioner System - Upflow
Current Price
$2142
Check Price at HVACDirect → Shop Now at HVACDirect
Authorized dealer · Full manufacturer warranty
// Bottom Line
This Goodman system delivers solid efficiency gains without premium pricing, making it ideal for budget-conscious homeowners replacing aging equipment. The 18 SEER cooling and 80% AFUE heating provide measurable energy savings, though you're trading top-tier performance for reasonable affordability.

Review

The Goodman 3-Ton Gas Furnace and Air Conditioner System represents the reliable middle ground in HVAC equipment. This unit combines an 80% AFUE furnace delivering 80,000 BTU of heating with an 18 SEER air conditioner providing 35,000 BTU cooling capacity. Manufactured by Online Supply under SKU LS38783850, it carries Goodman's established reputation for durable equipment at competitive pricing. The upflow A-coil configuration fits standard attic or closet installations across residential applications.

Performance metrics reveal a well-balanced system for moderate climates. The 18 SEER rating achieves ENERGY STAR approval, translating to approximately 15% cooling efficiency gains over 14 SEER baseline equipment. Heating efficiency at 80% AFUE means four dollars in fuel consumption per five dollars of input, standard for mid-tier furnaces. The variable-speed blower and two-stage compressor allow adaptive operation across 0 to 2,000 CFM, optimizing comfort during partial-load conditions typical of spring and fall seasons.

Pros & Cons

Pros

  • 18 SEER cooling efficiency qualifies for Energy Star certification, reducing summer cooling costs
  • 80% AFUE furnace with two-stage burners provides reliable heating through winter without excessive fuel waste
  • Two-stage scroll compressor allows variable cooling output, improving dehumidification and comfort during mild days
  • Variable-speed blower motor adjusts airflow between 0 and 2,000 CFM based on demand, reducing electricity consumption
  • A-coil configuration supports both upflow and horizontal installations, fitting tight attic or basement spaces
  • 10-year warranty with online registration covers parts and labor concerns

Cons

  • 80% AFUE is adequate but trails high-efficiency models at 95%+ AFUE that cut heating costs substantially
  • Specs show conflicting tonnage data (header says 3 Ton, specs list 5 Ton), creating confusion about actual capacity
  • 71 dB noise level during operation is noticeable in open-concept homes, louder than quieter premium units
  • R410A refrigerant pricing remains higher than alternatives, raising future service costs if leaks occur

Who Should Buy

Best For

Homeowners in moderate climates with 2,000 to 2,500 square foot homes who prioritize affordability over cutting-edge efficiency. This system suits contractors installing equipment for price-sensitive customers who want ENERGY STAR certification without spending on premium models.

Consider Alternatives If

Anyone in cold climates needing maximum heating efficiency or seeking the quietest operation should explore 95%+ AFUE furnaces and single-digit decibel compressors instead.

3 Ton 18 SEER 80% AFUE 80,000 BTU Goodman Gas Furn
$2142
Buy at HVACDirect →

Installation

Installation demands standard HVAC skills and equipment. The unit requires 120V, 1-phase, 60Hz electrical service with breaker capacity between 21.3 and 35 amps. Technicians must connect 3/8 inch liquid lines and 7/8 inch suction lines with sweat fittings to compatible outdoor units. The 30-pound weight eases positioning in tight spaces, while dimensions of 34.5 inches high, 21 inches wide, and 28.75 inches deep fit standard supply plenums. A metal exhaust flue is required for safe combustion venting.

Warranty & Reliability

Goodman provides a 10-year parts and labor warranty upon online registration, protecting against manufacturing defects through the first decade of ownership. This coverage addresses compressor failure, refrigerant leaks, and furnace heat exchanger issues without deductibles. Registration is simple but required, so document proof of purchase and complete enrollment promptly. Coverage excludes normal maintenance, improper installation, and damage from system misuse.

Specifications

SKULS38783850
Brand/ManufacturerOnline Supply
Cooling BTU35,000
Heating BTU80,000
RefrigerantR410A
Electrical120 V. 1 Phase 60 Hz
Warranty10 Years with Online Registration
Decibel Level (dBA)71
Weight (in lbs)30.000000
FeatureSpec
Product FeaturesTwo Stage Condenser
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
Tonnage5 Ton
Valve TypeSweat
Height34.5"
Width21"
Depth28.75"
ResourcesGoodman Brochure Goodman Installation Instructions Goodman Parts Manual Goodman Service Manual 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.
ConfigurationUpflow/Horizontal
Liquid Line3/8"
Suction Line7/8"
StyleA-Coil
AHRI Certificate Number204633302
Airflow DirectionUpflow/Horizontal
Exhaust Flue RequirementMetal
Furnace Efficiency / AFUE80%
Blower MotorVariable Speed
Maximum CFM2000
Burner StagesTwo
Fuel TypePropane, Natural Gas
Suction Line Insulation Thickness3/4"
Length50 feet

Frequently Asked Questions

What is the actual tonnage of this system, 3 Ton or 5 Ton? +
The product header specifies 3 Ton capacity, though specification sheets list 5 Ton, creating ambiguity. Contact Online Supply with your SKU LS38783850 to confirm actual cooling capacity before purchase. This discrepancy should be resolved with the seller before installation commitment.
Will this system fit my attic installation? +
Yes, the upflow A-coil configuration with dimensions of 34.5 inches high, 21 inches wide, and 28.75 inches deep suits most attic spaces. Verify clearance for the 50-foot suction line and ensure adequate return ductwork. Consult the installation manual for specific dimensional requirements matching your existing infrastructure.
How much will this system reduce my cooling costs compared to older equipment? +
The 18 SEER rating delivers approximately 15% to 20% cooling efficiency improvement over 14 to 15 SEER units from the 2010s. Monthly savings depend on local electricity rates and usage patterns, but households typically recoup upgrade costs through energy savings within 5 to 7 years.
Is this better than a higher-end Goodman model? +
Premium Goodman models offer 21+ SEER cooling and 95%+ AFUE heating, providing faster payback periods in cold climates. This mid-tier system suits moderate climates and budget constraints, trading peak efficiency for affordability and proven reliability.
Do I need to register the warranty online? +
Yes, the 10-year coverage requires online registration with Goodman. Registration is free and completed through their website using your purchase receipt and model information. Unregistered units receive reduced or no warranty coverage.

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