Picking a water heater is a series of yes/no decisions — tank or tankless, gas or electric, conventional or heat pump, 40 or 50 gallon. Each comparison page below walks through the actual tradeoffs without trying to push you toward one answer. Pick the comparison that matches your decision point.
Comparison directory
- Tank vs Tankless — the biggest decision. Upfront cost, lifetime cost, install complexity, real performance differences (32K monthly searches)
- Gas vs Electric — fuel decision. Operating cost, install requirements, regional considerations
- Heat Pump vs Gas — the modern electrification decision. Rebates, efficiency, install requirements
- 40 vs 50 Gallon — the most common sizing decision
- Hybrid vs Traditional Electric — when the heat pump premium pays back
Brand comparisons
For brand-vs-brand decisions, see the brand-specific vs hubs:
- Rinnai vs Navien — tankless
- Rheem vs AO Smith — tank
- Bradford White vs Rheem
- Navien vs Rinnai (cold-sandwich focus)
Quick verdict matrix
| If… | Buy… |
|---|---|
| Replacing in same location, same fuel, budget-conscious | Same type as current |
| Want endless hot water and have proper gas line | Tankless (Rinnai Sensei or Navien NPE-A2) |
| Have hydronic heat and need to replace boiler + WH | Combi boiler (Navien NCB or NFC) |
| Electricity is cheap and you want maximum rebates | Heat pump hybrid (AO Smith Voltex, Rheem ProTerra) |
| Cold climate, 3+ bathrooms, frequent simultaneous demand | 75-gallon tank or large tankless with recirc |
| Small condo, low usage, want cheap | 40-gallon electric tank |