Review
The Goodman 3 Ton 18 SEER system with 97% AFUE represents the efficiency tier that serious homeowners and contractors target when replacement costs justify premium equipment. Online Supply positions this unit competitively on price while maintaining specification parity with major distributors. The combination of modulating gas heating and two-stage cooling in a single package simplifies installation and minimizes coordination headaches. This downflow configuration works well for crawl spaces and specific ductwork layouts where space efficiency matters.
Performance specs tell a compelling efficiency story. The furnace delivers 100,000 BTU heating with 97% AFUE, meaning nearly all fuel converts to usable heat rather than escaping through the flue. Cooling produces 35,000 BTU at 18 SEER with a scroll compressor running at just 71 decibels, quieter than most window units. The variable-speed ECM blower motor handles up to 2,000 CFM and adjusts airflow demand in real time, reducing energy waste during partial-load operation. R410A refrigerant compatibility ensures modern efficiency standards, though R22 fallback support aids retrofits.
Pros & Cons
Pros
- 97% AFUE furnace efficiency ranks among the best available for gas heating systems
- 18 SEER cooling efficiency qualifies for Energy Star certification and most utility rebates
- Modulating furnace burner and variable-speed ECM blower motor optimize comfort and reduce runtime cycling
- Two-stage scroll compressor minimizes noise at 71 decibels, suitable for residential settings
- 10-year warranty with online registration provides solid coverage for parts and components
Cons
- 3-ton cooling capacity mismatches the 5-ton tonnage specification, creating confusion about actual system size and capacity
- 35 amp maximum breaker requirement demands dedicated electrical circuit and may need panel upgrade in older homes
- Downflow configuration limits installation flexibility and may not suit all basement or attic placements
Who Should Buy
Best For
Homeowners in mixed climates replacing older split systems who want best-in-class efficiency ratings and can absorb the electrical upgrade costs. Contractors building spec homes where Energy Star qualification helps with marketing and rebate programs.
Consider Alternatives If
Anyone with undersized electrical service or homes with space constraints, plus buyers needing systems larger than 5 tons should evaluate higher-capacity units.
Installation
Installation requires a 115V single-phase 60Hz circuit with 21.3 to 35 amp capacity, standard for most residential panels. Plastic PVC exhaust venting is mandatory for the furnace section, simplifying ductwork coordination. Suction and liquid line sizes at 7/8 inch and 3/8 inch respectively demand proper isolation and support to prevent vibration transmission. The 30-pound weight and compact 30 by 21 by 21 inch footprint fit most utility closets and mechanical rooms without major framing modifications.
Warranty & Reliability
The 10-year parts warranty kicks in upon online registration and covers manufacturing defects across all major components. This matches or exceeds competitor offerings at this price point and provides meaningful protection during the system's high-efficiency years. Labor and refrigerant are typically excluded, as is maintenance-related failure, so homeowners should budget for professional service contracts.
Specifications
| SKU | LS38783850 |
| Brand/Manufacturer | Online Supply |
| Cooling BTU | 35,000 |
| Heating BTU | 100,000 |
| 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 | 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. |
| AHRI Certificate Number | 7424272 |
| Airflow Direction | Downflow/Horizontal |
| Exhaust Flue Requirement | Plastic / PVC |
| Furnace Efficiency / AFUE | 97% |
| Blower Motor | Variable Speed - ECM |
| Maximum CFM | 2000 |
| Configuration | Upflow / Downflow |
| Burner Stages | Modulating |
| 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
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