A.O. Smith, founded 1874, headquartered in Milwaukee, Wisconsin. 7 models across 1 product types: 7 heat pump. All heat pump models
Why buyers end up in A.O. Smith
- Specialist: focused entirely on heat pump technology
- Top-tier efficiency: best model reaches UEF 3.88
- Smart-home ready: 3 models with Wi-Fi control
- Strong warranty: up to 10-year tank coverage
- Published noise data: 45 dB on quietest model
Where this brand is weaker
- No condensing tankless or gas tank models in our database
Market position
One of the largest dedicated water heater manufacturers in North America, with product lines spanning all major fuel types and price tiers
Known for: Largest US water heater manufacturer. Broad product range from value to premium. Strong retail presence at Lowe's and extensive pro channel.
Efficiency range
UEF 3.60 to 3.88
Across 7 models with published UEF ratings.
Below are all verified A.O. Smith models with published specs.
Models
Heat Pump Models
| Model | Brand | UEF | FHR | Height | Est. Cost/yr |
|---|---|---|---|---|---|
| HPTA-80-2 | A. O. Smith | 3.88 | 95 gal | 69" | ~$220 |
| HPTS-80-2 | A. O. Smith | 3.88 | 95 gal | 69" | ~$220 |
| HPTA-66-2 | A. O. Smith | 3.84 | 83 gal | 61" | ~$223 |
| HPTS-50-2 | A. O. Smith | 3.80 | 65 gal | 63" | ~$143 |
| HPTS-66-2 | A. O. Smith | 3.70 | 82 gal | 61.5" | ~$213 |
| HPTA-50-2 | A. O. Smith | 3.68 | 65 gal | 63" | ~$152 |
| HPTA-40-2 | A. O. Smith | 3.60 | 55 gal | 66" | ~$156 |
● Best in group
Beyond specs, here's the ownership experience with A.O. Smith.
Manufacturing
U.S. manufacturing footprint
- Ashland City, Tennessee (residential gas and electric - world's largest water heater factory)
- Johnson City, Tennessee (residential gas and electric)
- McBee, South Carolina (commercial gas and electric)
- Lebanon, Tennessee (residential and commercial boilers and storage tanks)
Where to buy
Channels: Retail, Wholesale, Contractor
Retail partners: Lowe's
Signature Series sold exclusively at Lowe's. ProLine sold through plumbing wholesale and contractors.
Technology
- heat pump (Signature 900)
- iCOMM smart connectivity
- Leak Watch / Leak Shield leak detection
- CoreGard anode rod
Product lines
Retail Lines
Signature 100 Value tier, 6-year warranty, dependable hot water at affordable cost
Signature 300 Mid tier, 9-year warranty, iCOMM smart connectivity and Leak Watch leak detection
Signature 500 Premium tier, 12-year warranty, smart connectivity with Leak Shield automatic shut-off
Signature 900 Top tier, 10-year warranty, hybrid heat pump technology, 3x efficiency vs standard electric
Pro Lines
ProLine Base tier for contractors and wholesalers, 6-year warranty
ProLine Master Mid tier with commercial-grade components, 8-year warranty
ProLine XE Premium high-efficiency tier including heat pump, tankless, and condensing models
Warranty
Signature 100 / ProLine 6-year limited
ProLine Master 8-year limited
Signature 300 9-year limited
Signature 900 10-year limited
Signature 500 12-year limited
Competitive across all tiers; top tiers (Signature 500) above industry average for tank units
Related
Sources. Company websites, ENERGY STAR, manufacturer spec sheets.Methodology