Ruud is Rheem\'s contractor-channel brand. AO Smith is the other major US residential manufacturer, primarily sold at Lowe\'s under multiple brand badges.
Manufacturer comparison
| Ruud (Rheem) | AO Smith | |
|---|---|---|
| Parent | Rheem corporate | AO Smith corporate |
| US tank manufacturing | Yes | Yes |
| US tankless | Yes (RTGH / Ultra Series) | Via Takagi subsidiary |
| Heat pump | ProTerra / Professional Hybrid | Voltex (best UEF in residential) |
Tier comparison
| Warranty tier | Ruud (Rheem) | AO Smith |
|---|---|---|
| 6-year tank | Professional Classic | Signature |
| 9-year tank | Professional Achiever Plus | Signature Select |
| 12-year tank | Professional Ultra | Signature Premier |
| 10-year hybrid | Professional Hybrid | Voltex |
When Ruud wins
- You work with a Rheem-affiliated plumber
- Tankless preference (Ruud Ultra Series at contractor channel; AO Smith only via Takagi)
- Contractor wholesale pricing
When AO Smith wins
- You shop at Lowe\'s (AO Smith Signature available; Ruud isn\'t)
- Voltex heat pump has slightly better UEF reputation (though comparable)
- Premium plumber-channel relationship with AO Smith dealer
Bottom line
Both Rheem and AO Smith make competent products at every tier. Choose by your distribution channel — contractor (Ruud) vs Lowe\'s retail (AO Smith Signature) vs Home Depot retail (Rheem).