Navien
Navien NPE-240A2
$2099
Best Tankless Water Heaters · head-to-head
Navien NPE-240A2 vs A.O. Smith ProLine XE ATI-540H-N
A sourced, side-by-side comparison. Navien NPE-240A2 is cheaper at $2099. Every spec and price links to its source.
A.O. Smith
A.O. Smith ProLine XE ATI-540H-N
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Full spec sheet
✓ marks the stronger figure where "more" — or "less", for price and weight — is unambiguously better.
| Spec |  Navien NPE-240A2 |  A.O. Smith ProLine XE ATI-540H-N |
|---|---|---|
| US price | $2099 | — |
| Brand | Navien | A.O. Smith |
| Released | — | — |
| Fuel type | natural-gas | natural-gas |
| Max flow rate (gpm) | 11.2 | 10 |
| Max btu per hour | 199900 | 199000 |
| Power input (kW) | — | — |
| Uniform energy factor | 0.95 | 0.93 |
| Condensing type | condensing | condensing |
| Min activation flow (gpm) | 0.5 | — |
| Vent type | pvc | pvc |
| Max temp (°F) | — | — |
| Heat exchanger warranty yrs | 15 | 15 |
| Wi-Fi enabled | No | — |
| Weight (lb) | 77 | — |
Sources — Navien NPE-240A2: navieninc.com (verified 2026-07-11). A.O. Smith ProLine XE ATI-540H-N: hotwater.com (verified 2026-07-11).
What's the difference between the Navien NPE-240A2 and A.O. Smith ProLine XE ATI-540H-N?
Where the two actually differ on the specs we track (3 of 12). Matching specs are omitted.
- Max flow rate (gpm): Navien NPE-240A2 11.2 vs A.O. Smith ProLine XE ATI-540H-N 10
- Max btu per hour: Navien NPE-240A2 199900 vs A.O. Smith ProLine XE ATI-540H-N 199000
- Uniform energy factor: Navien NPE-240A2 0.95 vs A.O. Smith ProLine XE ATI-540H-N 0.93