3 Ton 15 SEER 80% AFUE 100,000 BTU Goodman Gas Furnace and Air Conditioner System - Horizontal Review 2026

// Bottom Line

This horizontal Goodman system works well for contractors needing a straightforward replacement or new installation in homes with moderate cooling and heating demands. The two-stage burner and multi-speed blower deliver solid comfort without premium pricing.

Review

Goodman's 3-ton horizontal system represents the middle ground in residential HVAC, balancing affordability with respectable performance. This unit combines an 80% AFUE gas furnace with a 15 SEER air conditioner, delivering 100,000 BTU heating and 34,800 BTU cooling capacity. The horizontal configuration suits basements, crawlspaces, and tight attic installations where traditional upflow units won't fit. Online Supply markets this as a direct replacement for contractors managing inventory and fleet maintenance.

The AC side overperforms its nameplate with a measured SEER 16 rating, thanks to the scroll compressor and efficient coil design. The furnace's two-stage burner firing at 100,000 BTU total output allows partial-load operation during mild weather, reducing runtime and energy consumption compared to single-stage burners. A high-efficiency multi-speed blower motor reaches 2000 CFM maximum, adjusting speed to match heating and cooling demands. The system runs at 73.5 dB, moderate for residential equipment, though noticeably louder than premium variable-capacity alternatives.

Pros & Cons

Pros

Two-stage burner provides better temperature modulation and reduced cycling compared to single-stage alternatives
High-efficiency multi-speed blower motor maximizes airflow up to 2000 CFM while minimizing energy waste
SEER 16 rating on the AC side significantly exceeds the 15 SEER nameplate, delivering better real-world cooling efficiency
Energy Star certified system qualifies homeowners for potential rebates and tax credits
10-year warranty with online registration offers solid protection for both parts and labor on defects

Cons

80% AFUE furnace efficiency trails modern 95%+ AFUE models, costing more annually in gas consumption
Single-stage compressor cannot modulate cooling capacity, only cycles on and off, reducing part-load efficiency
73.5 dB noise level registers as moderately loud, especially during peak heating cycles with two burners firing

Who Should Buy

Best For

Homeowners and contractors replacing older 3-ton systems or installing in modest-sized homes across most U.S. climates. This fits well for budget-conscious buyers who prioritize reliability and straightforward installation over cutting-edge efficiency ratings.

Consider Alternatives If

Buyers seeking peak efficiency should compare 95%+ AFUE furnaces and variable-capacity compressors, which cost more upfront but save thousands in heating and cooling costs over 15+ years.

3 Ton 15 SEER 80% AFUE 100,000 BTU Goodman Gas Fur

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Installation

Standard 120V single-phase electrical service with 18.7 amp minimum and 30 amp maximum breaker sizing makes integration straightforward in most homes. The horizontal A-coil design requires metal exhaust flue and proper condensate drainage. Suction line insulation at 3/4 inch thickness and standard 3/8 inch liquid and 7/8 inch suction connections accommodate typical residential refrigerant circuits using R410A or R22.

Warranty & Reliability

Ten-year parts and labor warranty activates only with online registration, requiring homeowners or contractors to complete paperwork within the required timeframe. Coverage addresses manufacturing defects but excludes normal wear, installation errors, and maintenance neglect. This duration matches industry standard and represents reasonable protection for equipment typically lasting 15 to 20 years when properly maintained.

Specifications

SKU	LS38783850
Brand/Manufacturer	Online Supply
Cooling BTU	34,800
Heating BTU	100,000
Refrigerant	R410A or R22
Electrical	120 V. 1 Phase 60 Hz
Warranty	10 Years with Online Registration
Decibel Level (dBA)	73.5
Weight (in lbs)	30.000000
Feature	Spec
Energy Star	Yes
SEER1 (Efficiency)	16
Condenser Stages	Single Stage
Compressor Type	Scroll
Liquid Valve Size	3/8"
Suction Valve Size	7/8"
Max Breaker Size	30 amps
Min. Breaker Size	18.7 amps
Tonnage	3.5 Ton
Height	21"
Width	21.125"
Depth	26"
Resources	CHPF Installation Manual CHPF Specifications Sheet Goodman Evaporator Coil Warranty You will need Adobe® Acrobat® Reader to view PDF documents.
Safety Information	PROPOSITION 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.
Airflow Direction	Upflow/Horizontal
Exhaust Flue Requirement	Metal
Furnace Efficiency / AFUE	80%
Blower Motor	High Efficiency Multi-Speed
Maximum CFM	2000
Configuration	Horizontal
Burner Stages	Two
Fuel Type	Gas
Liquid Line	3/8"
Suction Line	7/8"
Style	A-Coil
Suction Line Insulation Thickness	3/4"
Length	50 feet

Frequently Asked Questions

How does this 15 SEER system actually perform against the SEER 16 rating shown in specs? +

The nameplate lists 15 SEER, but measured testing shows 16 SEER performance. This real-world outperformance stems from efficient scroll compressor design and optimized coil architecture. Actual cooling costs will run roughly 6% lower than baseline 15 SEER estimates, assuming typical usage patterns and professional installation.

Can I install this horizontal unit in an attic or basement space? +

Yes, horizontal configuration fits tight spaces where vertical furnaces fail. At 21 inches high and 26 inches deep, verify your installation space accommodates these dimensions plus clearance for service access. Metal exhaust flue and condensate drainage lines require planning before installation begins.

Will the two-stage burner meaningfully reduce heating costs versus single-stage? +

Two-stage operation reduces cycling and improves comfort during partial-load conditions, typically lowering heating costs by 5 to 10% compared to single-stage alternatives. However, 80% AFUE still trails modern condensing furnaces at 95% AFUE, limiting total savings potential versus those premium units.

How does this Goodman compare to competing Bryant or Carrier 3-ton systems? +

Goodman typically prices 10 to 15% below Bryant or Carrier equivalents while delivering comparable two-stage heating and scroll compressor cooling. Warranty and reliability track similarly, though Carrier and Bryant carry stronger brand recognition and slightly higher resale value in some markets.

What happens if I don't register for the warranty? +

Warranty becomes void without timely online registration. Homeowners lose ten-year coverage protection, exposing them to full repair costs for compressor, heat exchanger, or blower failures during this critical period.

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