4 Ton 15 SEER 97% AFUE 100,000 BTU Goodman Gas Furnace and Air Conditioner System - Downflow Review 2026

// Bottom Line

This Goodman system works best for homeowners replacing aging equipment in homes with downflow/horizontal ductwork and access to natural gas or propane. The 97% AFUE rating and variable-speed blower deliver measurable energy savings, making it ideal for cost-conscious buyers in moderate to cold climates.

Review

The Goodman 4-ton gas furnace and air conditioner system represents solid mid-range equipment for homeowners seeking efficient climate control without premium pricing. At $117 (likely per ton or a promotional price point), this downflow unit combines proven Goodman reliability with modern efficiency standards. The system includes both heating and cooling components, making it a complete replacement solution for older two-piece equipment.

Performance specifications highlight this unit's strengths in efficiency. The furnace delivers 97% AFUE with 100,000 BTU heating capacity and modulating burner stages that adjust output for comfort and savings. The cooling side provides 45,500 BTU at 16 SEER rating, backed by an Energy Star certification. The variable-speed ECM blower motor runs at up to 2,000 CFM while maintaining a reasonable 73 dB noise level, avoiding the constant hum of older single-speed motors.

Pros & Cons

Pros

97% AFUE furnace efficiency cuts heating costs compared to older 80-85% models
Variable-speed ECM blower motor reduces energy consumption and noise levels to 73 dB
Modulating burner stages provide precise temperature control rather than on-off cycling
16 SEER air conditioning unit meets Energy Star standards for cooling efficiency
Plastic/PVC exhaust flue compatibility simplifies installation in modern homes
10-year warranty with online registration provides solid long-term protection

Cons

Single-stage condenser limits cooling efficiency compared to two-stage models at higher SEER ratings
45,500 BTU cooling capacity is undersized for the 5-ton tonnage rating, creating a mismatch
Requires 208/230V single-phase power, limiting flexibility in some older residential installations
73 dB noise level is moderately loud for basement or utility room locations

Who Should Buy

Best For

Homeowners in gas-heated regions looking to replace 15-20 year old furnace and AC units who have downflow/horizontal ductwork and access to natural gas or propane. This system delivers strong efficiency gains and quiet operation at a competitive price point.

Consider Alternatives If

Buyers needing high-capacity cooling in hot climates should look at higher SEER models, and those with upflow-only ductwork applications need different configurations.

4 Ton 15 SEER 97% AFUE 100,000 BTU Goodman Gas Fur

$117

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Installation

This downflow unit requires PVC/plastic exhaust flue, which most modern homes accommodate easily. The 30 x 21 x 21 inch footprint fits standard utility closets and basement installations. Technicians need 208/230V single-phase power with 23.9 to 40 amp breaker capacity. Refrigerant lines are pre-sized at 3/8 inch liquid and 1 1/8 inch suction, with 50 feet of pre-insulated line included.

Warranty & Reliability

Goodman backs this system with a 10-year parts warranty when you register online, which is standard for their residential equipment. This covers compressor, coil, and furnace components, providing reasonable protection. Registration is straightforward and typically completed during professional installation. Coverage excludes labor, so budget separately for service calls.

Specifications

SKU	LS381183850
Brand/Manufacturer	Online Supply
Cooling BTU	45,500
Heating BTU	100,000
Refrigerant	R410A or R22
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	7424272
Airflow Direction	Downflow/Horizontal
Exhaust Flue Requirement	Plastic / PVC
Product Features	Rebate Available
Furnace Efficiency / AFUE	97%
Blower Motor	Variable Speed - ECM
Maximum CFM	2000
Configuration	Upflow / Downflow
Energy Star	Yes
Burner Stages	Modulating
Fuel Type	Propane, Natural Gas
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.
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

Why does a 5-ton system have only 45,500 BTU cooling capacity? +

This appears to be a specification inconsistency in the product listing. Standard 5-ton units deliver approximately 60,000 BTU cooling. You should verify actual cooling capacity with the manufacturer's AHRI certificate number 7424272 before purchasing to ensure it meets your home's cooling needs.

Can this downflow furnace be converted to upflow if I move it later? +

The specs indicate upflow/downflow configuration capability, suggesting some flexibility. However, conversion requires proper ductwork modification and re-certification. Your installer must confirm whether this specific unit can handle both directions, as some furnace designs have asymmetrical components that limit conversion.

How much will this system save on my heating bills compared to my 80 AFUE furnace? +

The 97% AFUE rating means 17 percentage points better efficiency than an 80 AFUE unit. On a typical $1,200 annual heating bill, you'd save roughly $204 per year, or about $2,040 over ten years, depending on gas prices and climate.

Should I choose this Goodman over higher-priced brands like Carrier or Lennox? +

Goodman offers excellent value for mid-range buyers. Carrier and Lennox command higher prices for marginally better efficiency and slightly extended warranties. At this price point, Goodman's 97% AFUE and variable-speed blower deliver comparable performance to costlier competitors, making it smart for budget-conscious buyers.

What does the 10-year warranty actually cover if my furnace breaks? +

The warranty covers parts like the heat exchanger, compressor, and blower motor for ten years with registration. Labor costs and refrigerant are your responsibility. Register immediately after installation to activate coverage and retain documentation for any future claims.

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