4 Ton 16 SEER 96% AFUE 120,000 BTU Goodman Gas Furnace and Air Conditioner System - Downflow Review 2026

// Bottom Line

This Goodman system works well for homeowners upgrading from older equipment who want high efficiency without premium pricing. The 96% AFUE heating and 16 SEER cooling make it an ENERGY STAR qualified choice suitable for most residential applications, especially in moderate to cold climates where furnace efficiency matters most.

Review

Goodman remains the volume leader in residential HVAC for good reason: this 4-ton combination system delivers practical efficiency at street-level pricing. The downflow A-coil configuration suits homes with basement or crawlspace installation, while the 120,000 BTU capacity covers typical single-family loads. At $3,253, it positions between builder-grade equipment and premium brands, making it the default choice for contractors and homeowners balancing performance against budget constraints.

The 96% AFUE rating means 96 cents of every heating dollar converts to home warmth, substantially beating 80% models common in older homes. Paired with 16 SEER cooling and 45,500 BTU capacity, this unit earns ENERGY STAR qualification. The variable-speed ECM blower adjusts airflow between 0 and 2000 CFM based on actual demand, preventing the energy waste of constant-speed motors. Two-stage burner modulation further improves comfort by varying heat output rather than cycling on and off repeatedly.

Pros & Cons

Pros

96% AFUE furnace efficiency exceeds federal minimum standards by significant margin, lowering heating costs
16 SEER cooling efficiency qualifies for ENERGY STAR certification and utility rebates
Variable speed ECM blower motor adjusts to actual heating and cooling demand, reducing runtime and energy waste
Two-stage burner provides modulating heat output for improved comfort and efficiency
10-year warranty with online registration covers parts and protects your investment
120,000 BTU heating capacity handles most single-family homes without oversizing

Cons

73 dB noise level runs slightly louder than premium competitors, noticeable during operation
Single-stage cooling condenser offers less efficiency than two-stage systems in variable conditions
Proprietary Online Supply branding may complicate service sourcing compared to direct Goodman units
40 amp maximum circuit breaker requirement needs adequate electrical service, limiting some retrofit applications

Who Should Buy

Best For

Homeowners replacing 10 to 15-year-old furnace and air conditioner systems who prioritize reliable heating efficiency and want to capture utility rebates. This system makes sense for occupied climates where furnace run time justifies the 96% AFUE investment over standard 80% models.

Consider Alternatives If

Anyone needing premium variable-capacity cooling should look at two-stage condenser units, and households in exclusively warm climates should prioritize air conditioning efficiency over furnace performance.

4 Ton 16 SEER 96% AFUE 120,000 BTU Goodman Gas Fur

$3253

Buy at HVACDirect →

Installation

This downflow unit requires 208/230V single-phase power and a 40-amp breaker, so confirm adequate electrical service before purchasing. PVC exhaust venting is required, which costs less than metal flue systems. Height of 30 inches and depth of 21 inches fit standard utility closets and basements. Technicians should allow 4-6 hours for complete furnace-condenser installation including refrigerant lines, electrical connections, and ductwork testing.

Warranty & Reliability

Ten-year parts warranty activates upon online registration at no cost, providing solid protection against manufacturing defects. This covers compressor, heat exchanger, and major components but excludes wear items and improper installation. Registration is straightforward and extends coverage beyond industry standard five years, adding real resale value and peace of mind for second owners.

Specifications

SKU	LS381183850
Brand/Manufacturer	Online Supply
Cooling BTU	45,500
Heating BTU	120,000
Refrigerant	R410A
Electrical	208 / 230 V. 1 Phase 60 Hz
Warranty	10 Years with Online Registration
Decibel Level (dBA)	73
Weight (in lbs)	48.000000
Feature	Spec
AHRI Certificate Number	7368845
Airflow Direction	Downflow/Horizontal
Exhaust Flue Requirement	Plastic / PVC
Product Features	Rebate Available
Furnace Efficiency / AFUE	96%
Blower Motor	Variable Speed - ECM
Maximum CFM	2000
Configuration	Upflow / Downflow
Energy Star	Yes
Burner Stages	Two
Fuel Type	Propane, Natural Gas
Height	30"
Width	24.5"
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.
Replaces	GSX16S481
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	23.9 amps
Tonnage	5 Ton
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 does 16 SEER actually mean for my cooling costs? +

SEER measures cooling efficiency; 16 SEER means the system removes 16 units of heat per 1 unit of electrical energy consumed. Compared to 10 SEER older units, you'll see approximately 35-40% lower summer electricity usage. Exact savings depend on local climate, home insulation, and thermostat settings, but expect $30-60 monthly reduction in humid regions.

Can I install this in an upflow position instead of downflow? +

Yes, the unit supports both upflow and downflow configurations. However, coil orientation and return duct placement differ between setups. Have your installer determine positioning before delivery, as coil installation direction affects drainage and refrigerant flow. Improper orientation causes performance loss and potential water damage.

How does the two-stage burner improve efficiency? +

Two-stage burners run at lower output (approximately 65-70% capacity) during mild weather instead of cycling fully on and off. This reduces startup losses and maintains steadier home temperatures. On very cold days, it fires at full 120,000 BTU output. The result is smoother heating and approximately 5-8% better efficiency than single-stage burners.

How does this compare to higher-SEER units from Lennox or Carrier? +

Premium brands offer 18-20 SEER systems with variable-capacity compressors and two-stage condensers, costing $4,500-6,000 installed. This 16 SEER Goodman delivers 85-90% of their cooling efficiency at 60% of the price. Pick this for value-conscious decisions; choose premium brands if maximum efficiency and quietest operation justify extra cost.

Does the warranty cover refrigerant and labor? +

The 10-year parts warranty covers compressor, coil, and components, but excludes refrigerant replacement and service labor. You pay for technician time and any refrigerant needed beyond factory charge. Extended service plans are available separately through dealers if additional labor coverage matters.

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