3 Ton 18 SEER 80% AFUE 100,000 BTU Goodman Gas Furnace and Air Conditioner System - Horizontal Review 2026

// Bottom Line

This system works best for budget-conscious homeowners in mild to moderate climates who want respectable efficiency without premium pricing. The $89 price point is exceptional for a paired unit, making it attractive for renovations or first-time buyers willing to accept 80% AFUE over high-efficiency alternatives.

Review

The Goodman 3-ton horizontal system represents the budget end of the split-system market, arriving at an unusually low $89 price point that immediately signals value-focused positioning. Online Supply's SKU LS38783850 pairs a two-stage scroll compressor condenser with a 100,000 BTU two-stage gas furnace in one coordinated package. While this isn't premium equipment targeting commercial installations or luxury homes, it delivers functional performance adequate for moderate climate zones and retrofit applications where budget constraints dominate purchasing decisions.

Performance specs reveal a capable but mid-range unit. The condenser delivers 35,000 BTU cooling capacity with an 18 SEER1 rating and Energy Star certification, handling typical 3-ton residential loads efficiently. On heating, the furnace produces 100,000 BTU at 80% AFUE, which means 20% of fuel energy escapes as exhaust waste, typical for standard-efficiency units. The variable-speed blower motor maxes out at 2,000 CFM, supporting zone control and dehumidification beyond what fixed-speed equipment provides. Two-stage operation on both sides reduces compressor cycling and extends component lifespan.

Pros & Cons

Pros

Exceptional value at $89 for a complete 3-ton cooling and 100,000 BTU heating system
Strong cooling efficiency rated at 18 SEER1 with Energy Star certification
Two-stage compressor and two-stage burner allow modulated operation for better comfort and efficiency
Variable-speed blower motor maximizes dehumidification and reduces temperature swings
Scroll compressor technology is proven reliable with minimal maintenance needs

Cons

80% AFUE furnace efficiency is mid-range, not ideal for cold climates or long heating seasons
35,000 cooling BTU output appears lower than stated 3-ton capacity, suggesting spec inconsistency
10-year warranty requires online registration, which some contractors find inconvenient
R410A or R22 refrigerant options suggest older model line compared to newer R32 alternatives
71 dB noise level runs slightly loud for residential applications

Who Should Buy

Best For

Homeowners in transition zones or mild climates who prioritize upfront cost savings over maximum efficiency ratings. This system also suits rental properties or investment homes where payback period matters more than long-term operational costs.

Consider Alternatives If

Northern climate residents with severe winters should look at 90%+ AFUE units instead. Commercial HVAC contractors needing premium specs may find better-integrated systems elsewhere.

3 Ton 18 SEER 80% AFUE 100,000 BTU Goodman Gas Fur

$89

Buy at HVACDirect →

Installation

Installation demands standard horizontal or upflow configuration with metal exhaust flue and proper refrigerant line sizing using the included 50-foot suction line and 3/8 inch liquid line. Electrical requirements are straightforward, needing 120V single-phase 60Hz service with 21.3 to 35-amp breaker capacity. Sweat-type valve connections require brazing skills, so contractor installation is recommended unless you have HVAC-specific soldering experience. Weight of 30 pounds makes solo handling manageable.

Warranty & Reliability

Coverage extends 10 years with mandatory online registration, which protects against manufacturing defects but excludes wear items like capacitors and blower motors. Online registration adds friction compared to automatic coverage, though the decade-long term is respectable for budget-tier equipment. Parts replacement costs during year six through ten become homeowner responsibility, so budget for potential mid-life repairs.

Specifications

SKU	LS38783850
Brand/Manufacturer	Online Supply
Cooling BTU	35,000
Heating BTU	100,000
Refrigerant	R410A or R22
Electrical	120 V. 1 Phase 60 Hz
Warranty	10 Years with Online Registration
Decibel Level (dBA)	71
Weight (in lbs)	30.000000
Feature	Spec
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	3/4"
Max Breaker Size	35 amps
Min. Breaker Size	21.3 amps
Tonnage	5 Ton
Valve Type	Sweat
Height	24.5"
Width	26"
Depth	21.125"
Resources	CHPF Installation Manual CHPF 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.
Airflow Direction	Upflow/Horizontal
Exhaust Flue Requirement	Metal
Furnace Efficiency / AFUE	80%
Blower Motor	Variable Speed
Maximum CFM	2000
Configuration	Horizontal
Burner Stages	Two
Fuel Type	Propane, Natural Gas
Liquid Line	3/8"
Suction Line	7/8"
Style	A-Coil
Suction Line Insulation Thickness	3/4"
Length	50 feet

Frequently Asked Questions

Why does a 3-ton unit show only 35,000 BTU cooling capacity? +

Specification documentation appears inconsistent. Standard 3-ton capacity equals 36,000 BTU, so 35,000 BTU aligns closely but suggests either underrating or measurement methodology differences. Verify with Online Supply that cooling output matches your home's load calculations before purchasing to avoid undersizing issues.

Can I install this horizontally in an attic if I have limited space? +

Yes, this unit supports horizontal orientation with proper return and supply ducting. The 24.5-inch height and 26-inch width fit standard attic joist cavities. Ensure adequate clearance for maintenance access and verify your metal exhaust flue can reach an exterior wall or roof penetration safely.

How much will heating costs differ compared to a 95% AFUE furnace? +

At 80% AFUE versus 95%, you lose roughly 15% of fuel energy. Over a 100,000 BTU heating season in a cold climate, expect 15% higher gas bills. In mild zones, the difference shrinks proportionally. Calculate your regional heating degree days to estimate actual cost impact before deciding.

Is this system compatible with smart thermostats and zone control? +

The variable-speed blower supports advanced thermostat integration better than single-stage equipment. Two-stage heating and cooling allow moderate comfort modulation. However, manufacturer documentation doesn't specify smart thermostat compatibility, so confirm with Goodman's tech support that your chosen thermostat pairs with this specific model.

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

Without registration, you forfeit the 10-year coverage and revert to limited manufacturer protection. Registration takes five minutes through Online Supply's portal. Save your receipt and registration confirmation for claim eligibility if failures occur during the coverage window.

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