3.5 Ton 16 SEER 96% AFUE 80,000 BTU Goodman Gas Furnace and Air Conditioner System - Downflow Review 2026

// Bottom Line

This Goodman system excels for homeowners seeking strong heating and cooling efficiency without premium pricing. The 96% AFUE furnace and 16 SEER air conditioner make it ideal for moderate to cold climates where both seasons demand reliable performance.

Review

Goodman's gas furnace and air conditioner combo targets the mid-market segment where efficiency and reliability matter without excessive cost. This downflow system combines an 80,000 BTU furnace rated at 96% AFUE with a 42,000 BTU air conditioner delivering 16 SEER cooling. The variable-speed ECM blower and two-stage burner indicate thoughtful engineering beyond basic models. Online Supply offers this as a complete system solution for contractors and homeowners managing separate HVAC replacements or new installations.

The heating side performs exceptionally well with 96% AFUE efficiency, meaning 96 cents of every energy dollar converts to usable heat. Two burner stages allow the furnace to run at lower capacity during mild weather, reducing energy consumption. On cooling, the 16 SEER rating exceeds standard efficiency requirements and qualifies for Energy Star status. The scroll compressor and 1600 CFM maximum airflow deliver adequate performance for the stated tonnage, though the single-stage compressor cannot modulate cooling output on partial-load days.

Pros & Cons

Pros

96% AFUE furnace efficiency reduces heating costs significantly versus older 80-85% models
16 SEER air conditioner qualifies for Energy Star certification and utility rebates
Variable-speed ECM blower motor optimizes airflow and reduces energy waste year-round
Two-stage burner provides flexible heating output for better comfort and efficiency
Scroll compressor technology delivers reliable cooling with 10-year warranty upon registration
PVC flue exhaust compatibility simplifies retrofit installations in many homes

Cons

Single-stage air conditioner cannot modulate cooling capacity on mild days, reducing efficiency in temperate climates
73 dB noise level is audible during operation and louder than some premium models at 68-70 dB
SKU and specs show tonnage mismatch: title claims 3.5 tons but specs list 5 tons, creating confusion about actual cooling capacity

Who Should Buy

Best For

Contractors and homeowners in heating-dominant climates where furnace performance matters most. This system works well for split installations where upgrading an existing furnace and replacing an older AC unit separately.

Consider Alternatives If

Buyers in hot climates who need maximum cooling efficiency, or those seeking premium quiet operation. The tonnage specification discrepancy also suggests due diligence is needed before purchase.

3.5 Ton 16 SEER 96% AFUE 80,000 BTU Goodman Gas Fu

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Installation

Downflow configuration suits basements and crawlspaces with underfloor ductwork. Requires 115V single-phase 60Hz power with 23.5 to 40 amp breaker capacity, standard in most homes. PVC plastic flue compatibility simplifies retrofit work. Suction line insulation (1/2 inch over 50 feet) prevents moisture and maintains efficiency. A-coil style demands proper drainage and condensate handling during installation.

Warranty & Reliability

Goodman provides 10-year comprehensive coverage upon online registration. This protects major components including the compressor, heat exchanger, and coil against manufacturing defects. Registration is required to activate full warranty benefits. This coverage period is competitive for mid-tier equipment and provides meaningful protection for homeowners.

Specifications

SKU	LS381183850
Brand/Manufacturer	Online Supply
Cooling BTU	42,000
Heating BTU	80,000
Refrigerant	R410A or R22
Electrical	115 V. 1 Phase 60 Hz
Warranty	10 Years with Online Registration
Decibel Level (dBA)	73
Weight (in lbs)	48.000000
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	40 amps
Min. Breaker Size	23.5 amps
Tonnage	5 Ton
Height	30"
Width	21"
Depth	21"
Resources	CAPF Installation Manual CAPF 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.
AHRI Certificate Number	7368843
Airflow Direction	Downflow/Horizontal
Exhaust Flue Requirement	Plastic / PVC
Product Features	Rebate Available
Furnace Efficiency / AFUE	96%
Blower Motor	Variable Speed - ECM
Maximum CFM	1600
Configuration	Upflow / Downflow
Burner Stages	Two
Fuel Type	Propane, Natural Gas
Liquid Line	3/8"
Suction Line	1 1/8"
Style	A-Coil
Suction Line Insulation Thickness	1/2"
Length	50 feet

Frequently Asked Questions

What's the actual cooling tonnage, 3.5 or 5 tons? +

The product listing shows conflicting information. Title specifies 3.5 tons but specifications list 5 tons tonnage. The 42,000 BTU cooling capacity actually matches 3.5 tons more accurately than 5 tons. Verify with the seller before purchasing to confirm the correct unit size.

Can this furnace use R22 refrigerant, or is it R410A only? +

Specifications indicate compatibility with both R410A and R22 refrigerant options. However, confirm with your HVAC contractor which refrigerant the specific unit ships with, as R22 availability is limited and more expensive than R410A in most markets.

How much will this system reduce my heating bills compared to an 80% AFUE furnace? +

The 96% AFUE rating versus 80% AFUE represents a 20% improvement in fuel efficiency. On a typical $1,200 annual heating bill, you could save approximately $240 yearly. Exact savings depend on fuel prices, climate zone, and your home's insulation quality.

Is 16 SEER good enough, or should I wait for SEER2 ratings? +

16 SEER is excellent and represents high-efficiency cooling. The industry is transitioning to SEER2 ratings, which are slightly lower numerically due to harder testing standards. A 16 SEER unit typically equals roughly 13 SEER2. This system remains competitive regardless.

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

Without online registration, you forfeit the 10-year comprehensive coverage. Only limited or default warranty applies, typically 1-2 years. Registration is essential to protect your investment and ensure coverage eligibility.

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