4 Ton 17 SEER 80% AFUE 100,000 BTU Goodman Gas Furnace and Air Conditioner System - Upflow Review 2026

// Bottom Line

This Goodman combo works well for homeowners upgrading from older single-stage systems and needing reliable, affordable heating and cooling without premium efficiency pricing. The two-stage design and variable-speed blower deliver solid comfort and energy savings for moderate climates.

Review

Goodman has built its reputation on dependable, affordable HVAC systems, and this 4-ton gas furnace and air conditioner combination reflects that market position. The system delivers 100,000 BTU heating capacity paired with 47,000 BTU cooling output, making it suitable for mid-sized homes in moderate climates. This SKU LS381183850 from Online Supply represents the practical middle ground between budget units and high-efficiency premium systems that many contractors specify for residential retrofit jobs.

Performance metrics show an 80% AFUE furnace with two-stage burners and a matching two-stage condenser with 17 SEER cooling efficiency. The variable-speed blower motor maxes out at 2,000 CFM while maintaining relatively quiet operation at 72 dBA. Using R410A refrigerant and a scroll compressor, the system runs on 208/230V single-phase power with breaker requirements between 26.3 and 45 amps, keeping electrical upgrades minimal for most installations.

Pros & Cons

Pros

Two-stage heating and cooling reduces energy waste during partial-load operation, improving comfort and efficiency
17 SEER rating meets Energy Star requirements for potential tax credits in some jurisdictions
Variable-speed blower motor runs quietly at 72 dBA and adjusts airflow to match demand
Compact footprint at 30 inches tall fits standard upflow closet installations
10-year warranty with registration provides reasonable protection against manufacturing defects
Two fuel options (natural gas or propane) offer installation flexibility

Cons

80% AFUE is standard efficiency for mid-tier furnaces, not high-efficiency like 95% AFUE models that reduce heating bills 10-15% more
5-ton cooling capacity exceeds the 4-ton heating capacity, creating a minor system mismatch that wastes cooling potential
17 SEER (SEER1) is outdated metric; modern units list SEER2, making direct comparisons to current products difficult
Price listed as $0 makes true value assessment impossible without actual cost data

Who Should Buy

Best For

Contractors installing complete systems in rental properties, multi-family buildings, or budget-conscious residential upgrades will appreciate the Goodman reliability and straightforward two-stage design. Homeowners in moderate climates seeking mid-range efficiency without premium pricing will find this system delivers solid performance and reasonable operating costs.

Consider Alternatives If

Those prioritizing maximum energy efficiency should look at 95% AFUE furnaces paired with 18+ SEER2 air conditioners, which offer substantially lower annual operating costs despite higher upfront investment.

4 Ton 17 SEER 80% AFUE 100,000 BTU Goodman Gas Fur

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Installation

Installation requires metal exhaust flue for the furnace, standard for gas systems. The compact 30 x 24.5 x 21 inch footprint fits typical upflow closet placement. Refrigerant lines use industry-standard 3/8 inch liquid and 1 1/8 inch suction connections with 1/2 inch insulation on the 50-foot line set. Two-stage configuration demands proper thermostat wiring to access both heating and cooling stages.

Warranty & Reliability

Goodman provides a solid 10-year parts warranty when you register the unit within 30 days of installation. This covers the furnace, condenser, and evaporator coil against manufacturing defects. Registration is straightforward online and gives contractors valuable documentation. Note that labor is not covered, so installation quality from your contractor matters significantly.

Specifications

SKU	LS381183850
Brand/Manufacturer	Online Supply
Cooling BTU	47,000
Heating BTU	100,000
Refrigerant	R410A
Electrical	208 / 230 V. 1 Phase 60 Hz
Warranty	10 Years with Online Registration
Decibel Level (dBA)	72
Weight (in lbs)	48.000000
Feature	Spec
Airflow Direction	Upflow/Horizontal
Exhaust Flue Requirement	Metal
Furnace Efficiency / AFUE	80%
Blower Motor	Variable Speed
Maximum CFM	2000
Configuration	Upflow / Downflow
Burner Stages	Two
Fuel Type	Propane, Natural Gas
Height	30"
Width	24.5"
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.
Product Features	Two Stage Condenser
Energy Star	Yes
SEER1 (Efficiency)	18
Condenser Stages	Two Stage
Compressor Type	Scroll
Liquid Valve Size	3/8"
Suction Valve Size	1 1/8"
Max Breaker Size	45amps
Min. Breaker Size	26.3 amps
Tonnage	5 Ton
Valve Type	Sweat
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 is the cooling capacity 5 tons when this is marketed as a 4-ton system? +

The 47,000 BTU cooling output actually represents approximately 3.9 tons, so there's a minor spec inconsistency. This oversizing won't harm performance but suggests the system was designed for flexibility. Ensure your heating load calculation justifies the 100,000 BTU furnace to avoid short-cycling.

Can I convert this from natural gas to propane after installation? +

Yes, Goodman furnaces accept both fuels, but conversion requires replacing the burner orifices and adjusting air-to-fuel ratios. Have a qualified technician perform this work. Do not attempt DIY conversion, as incorrect settings create safety and efficiency problems.

Is 17 SEER good efficiency compared to what's available today? +

17 SEER (SEER1 rating) was solid five years ago but falls below modern standards. Current units achieve 18-22 SEER2, which uses updated testing that shows real-world performance better. SEER2 ratings run 20-25% lower numerically than SEER1, so direct comparison is misleading. This system offers fair, not excellent, efficiency.

How does the two-stage design improve efficiency compared to single-stage units? +

Two-stage heating and cooling runs at lower capacity during mild weather, reducing cycling losses and improving comfort. Single-stage systems run full-blast whenever called, wasting energy. Two-stage systems cut energy use 10-15% in moderate climates but show smaller savings in extreme climates where full capacity runs constantly.

What does the 10-year warranty actually cover if something fails? +

Parts replacement for manufacturing defects in the furnace, condenser, and evaporator coil. Does not cover refrigerant loss, labor, or damage from improper installation or maintenance. Requires timely registration. Refrigerant leaks typically cost $500-1,200 to repair, with warranty covering only the part, not the service call.

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