3 Ton 18 SEER 96% AFUE 120,000 BTU Goodman Gas Furnace and Air Conditioner System - Downflow Review 2026

// Bottom Line

This Goodman system delivers solid efficiency for mixed climates where cooling and heating both matter, especially for contractors needing a reliable 3-ton split system without premium pricing. Best suited for retrofit jobs in moderate climates where 18 SEER cooling and 96% AFUE heating provide meaningful energy savings without oversizing.

Review

Goodman builds durable residential HVAC equipment that contractors have trusted for decades, and this 3-ton split system reflects that reputation. The combination of 18 SEER air conditioning and 96% AFUE gas heating targets the sweet spot for retrofit installations in mixed climates where both seasonal demands matter. At $3,225, it undercuts premium brands like Lennox and Carrier by 25-40% while maintaining respectable efficiency ratings and a decade-long warranty.

The cooling side delivers 35,000 BTU using a scroll compressor with two-stage operation and R410A or R22 refrigerant compatibility, hitting that 18 SEER mark through intelligent staging rather than brute force. On the heating side, the 120,000 BTU furnace achieves 96% AFUE with a two-stage burner and variable-speed ECM blower motor rated for 2,000 CFM. This modulation approach reduces noise (71 dB) and electricity waste compared to single-stage competitors, though it does require careful sizing to avoid oversizing mistakes.

Pros & Cons

Pros

18 SEER cooling efficiency qualifies for Energy Star and reduces summer utility costs by 20-30% versus 13 SEER baseline units
96% AFUE furnace means only 4% of heating fuel is wasted, excellent for natural gas and propane heating seasons
Two-stage compressor and burner allow the system to modulate capacity, reducing short cycling and improving comfort
Variable-speed ECM blower motor runs only as fast as needed, cutting electricity consumption and noise levels
10-year warranty with online registration covers parts, providing decent protection for residential and light commercial applications

Cons

Spec sheet shows 5 Ton tonnage capacity but product title claims 3 Ton, creating confusion about actual cooling output and proper sizing
71 dB noise level is moderately loud, not ideal if outdoor condenser is near bedrooms or quiet spaces
Requires 21.3 to 35 amp breaker and 115V single-phase power, necessitating electrical upgrade in some older homes

Who Should Buy

Best For

Contractors replacing older systems in homes with both significant cooling and heating needs will appreciate the 18 SEER and 96% AFUE combination at this price. Homeowners in zones 4-6 seeking equipment that performs well in shoulder seasons and handles both AC and heat will see attractive payback periods.

Consider Alternatives If

Skip this if you live in a heating-only climate or need quiet outdoor operation near sensitive areas, or if your home electrical service cannot support a 21-35 amp breaker without major upgrades.

3 Ton 18 SEER 96% AFUE 120,000 BTU Goodman Gas Fur

$3225

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Installation

Downflow configuration fits basement or attic installations where horizontal discharge works. Requires plastic PVC exhaust venting and standard refrigerant line sets (3/8 inch liquid, 3/4 inch suction). Electrical needs 115V single phase at 21.3 to 35 amps, potentially requiring breaker panel work in older homes. Sweat-type connections demand soldering skills or professional installation.

Warranty & Reliability

10-year parts coverage comes standard with online registration, protecting against compressor failure and most internal components. This is middle-of-the-road coverage compared to Carrier's 10-year compressor specific and Goodman's extended options. Labor and refrigerant are typically not covered, so negotiate service plan details with your installer upfront.

Specifications

SKU	LS38783850
Brand/Manufacturer	Online Supply
Cooling BTU	35,000
Heating BTU	120,000
Refrigerant	R410A or R22
Electrical	115 V. 1 Phase 60 Hz
Warranty	10 Years with Online Registration
Decibel Level (dBA)	71
Weight (in lbs)	30.000000
Feature	Spec
Product Features	Rebate Available
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	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.
AHRI Certificate Number	7368845
Airflow Direction	Downflow/Horizontal
Exhaust Flue Requirement	Plastic / PVC
Furnace Efficiency / AFUE	96%
Blower Motor	Variable Speed - ECM
Maximum CFM	2000
Configuration	Upflow / Downflow
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 the listing say 3 Ton but the specs show 5 Ton? +

This appears to be a data error in the spec sheet. The 35,000 BTU cooling capacity and product title indicate 3-ton rating. Always verify against the AHRI certificate number 7368845 before purchasing, as tonnage directly affects system sizing and warranty eligibility.

Can this system retrofit into an existing ductwork with 3-ton capacity? +

Yes, downflow configuration works with most existing forced-air systems. However, verify your ducts are sized for proper CFM (2,000 max on this unit). Undersized ducts will reduce efficiency and cause the system to cycle short, defeating the two-stage advantage.

How much will 18 SEER actually save compared to an 13 SEER unit? +

In moderate climates with 600-800 cooling hours annually, expect 20-30% lower AC electricity costs. In high-humidity zones (1,000+ hours), savings approach 35%. Combined with 96% AFUE heating, total utility savings typically reach 25-35% versus 10-year-old equipment.

How does this compare to Lennox or Carrier at similar price points? +

Goodman matches efficiency (18 SEER, 96% AFUE) but offers less premium brand cachet and shorter warranty periods. Lennox and Carrier often bundle smart controls and extended warranties, justifying higher prices. Goodman wins on raw price-to-performance ratio for cost-conscious contractors.

Is the 10-year warranty good enough for resale? +

Yes, transferable registration helps home resale value. However, confirm transferability with Online Supply. Many buyers prefer Carrier or Lennox simply for brand recognition, though this Goodman system is mechanically equivalent in reliability.

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