3.5 Ton 13 SEER 80% AFUE 80,000 BTU Goodman Gas Furnace and Air Conditioner System - Upflow Review 2026

// Bottom Line

This Goodman system works best for homeowners replacing older equipment who prioritize affordability over peak efficiency. The two-stage burner and multi-speed blower deliver reasonable comfort, though 80% AFUE means higher heating costs than premium alternatives.

Review

Goodman's 3.5 ton gas furnace and air conditioner system represents the practical middle ground for budget-conscious HVAC replacements. This upflow configuration delivers 80,000 BTU of heating output and 42,000 BTU of cooling capacity, sizing appropriately for homes in the 1,400-1,600 square foot range. While not cutting-edge, it's a reliable workhorse that prioritizes affordability without sacrificing essential functionality.

Performance specs tell a straightforward story. The 80% AFUE rating means approximately 80 cents of every heating dollar reaches your home, with the rest lost through the metal flue. On cooling, the 13 SEER rating falls below today's minimum standards (14 SEER in most markets) but handles moderate cooling loads competently. The high-efficiency multi-speed blower adjusts CFM up to 2,000, reducing temperature swings compared to single-speed designs. Electrical requirements are modest at 208-230V single-phase with a 40-amp maximum breaker.

Pros & Cons

Pros

Two-stage gas burner reduces short cycling and improves comfort compared to single-stage units
High-efficiency multi-speed blower motor optimizes airflow across heating and cooling seasons
13 SEER rating provides mid-range cooling efficiency for moderate climates
Compact 30x21x21 inch footprint fits tight installation spaces
10-year warranty with online registration offers reasonable protection

Cons

80% AFUE is below current industry standards; premium models reach 95%+
Not Energy Star certified, limiting efficiency rebate eligibility in many regions
Single-stage condenser limits cooling efficiency optimization
75 dBA noise level runs louder than high-end competitors during operation

Who Should Buy

Best For

This system suits cost-conscious homeowners in mild to moderate climates replacing 15+ year old equipment. It's particularly appropriate for rental properties or secondary residences where operational simplicity and lower upfront cost matter more than premium efficiency.

Consider Alternatives If

Skip this if you live in a climate with extreme heating demands, qualify for efficiency rebates, or plan to stay in your home 15+ years, as the low AFUE will cost significantly more to operate.

3.5 Ton 13 SEER 80% AFUE 80,000 BTU Goodman Gas Fu

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Installation

Installation complexity is straightforward for licensed HVAC contractors. The unit requires metal exhaust flue, standard 3/8-inch liquid and 7/8-inch suction line connections with sweat valves, and 3/8-inch suction line insulation. Upflow/downflow flexibility lets installers adapt to basement or attic placement. Pre-charged with R410A refrigerant, it integrates easily with compatible evaporator coils using standard ductwork configurations.

Warranty & Reliability

The 10-year parts warranty activates upon online registration, protecting against compressor and component failures. This matches industry baseline for mid-tier equipment. Coverage is straightforward but doesn't extend labor costs or include system tune-ups, so budget separately for annual maintenance to preserve the warranty and efficiency.

Specifications

SKU	LS38783830
Brand/Manufacturer	Online Supply
Cooling BTU	42,000
Heating BTU	80,000
Refrigerant	R410A
Electrical	208 / 230 V. 1 Phase 60 Hz
Warranty	10 Years with Online Registration
Decibel Level (dBA)	75
Weight (in lbs)	30.000000
Feature	Spec
Airflow Direction	Upflow/Horizontal
Exhaust Flue Requirement	Metal
Furnace Efficiency / AFUE	80%
Blower Motor	High Efficiency Multi-Speed
Maximum CFM	2000
Configuration	Upflow / Downflow
Burner Stages	Two
Fuel Type	Gas
Height	30"
Width	21"
Depth	21"
Resources	CAPT Installation Manual CAPT 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.
Energy Star	No
SEER1 (Efficiency)	13
Condenser Stages	Single Stage
Compressor Type	Reciprocating
Liquid Line	3/8"
Suction Line	7/8"
Liquid Valve Size	3/8"
Max Breaker Size	40 amps
Min. Breaker Size	23.9 amps
Tonnage	5 Ton
Valve Type	Sweat
Style	A-Coil
Suction Line Insulation Thickness	3/8"
Length	30 feet

Frequently Asked Questions

Why is 80% AFUE a problem if the unit works fine? +

An 80% AFUE unit wastes 20% of fuel heating costs yearly. Over 15 years in a cold climate, upgrading to 95% AFUE saves $3,000-5,000 in heating bills. The lower initial cost is offset by higher operating expenses, making it better for short-term ownership.

Will this system fit my existing ductwork? +

The upflow/downflow configuration accommodates most standard residential ducts. However, verify your existing evaporator coil compatibility before purchasing. The system's 2,000 CFM maximum requires properly sized ducts, ideally 6-8 inches in diameter for main trunk lines.

How does two-stage heating compare to single-stage? +

Two-stage burners modulate between approximately 60% and 100% capacity, reducing on-off cycling and improving temperature consistency. You'll notice fewer furnace startups and more even heating than single-stage units, resulting in modest comfort gains.

Is 13 SEER adequate, or should I wait for a newer model? +

13 SEER is acceptable for mild climates but underperforms in hot regions. Modern units reach 14-16 SEER. If air conditioning runs 6+ months yearly, a higher SEER rating pays back in 5-7 years through lower electric bills.

Does the 10-year warranty cover everything? +

The warranty covers parts only, not labor or service calls. Registration is mandatory to activate it. No coverage for wear items or maintenance, so plan annual inspections to keep the warranty valid and system efficient.

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