Gas tankless · high draw
Navien NPE-xxA2
The Navien NPE-xxA2 line holds three certified rating sets of gas tankless water heaters, 4 model numbers sold under two brand names, listed by Navien and Vesta.DS. Gas input runs from 150,000 to 199,000 Btu/h, and max flow at a 67 °F rise runs from 4.3 to 5.6 gal/min. Navien NPE-180A2 lists 4.3 gal/min, the third lowest of the 40 gas tankless sets (shared by two sets). Navien NPE-180A2, the set with the most model numbers, rates 0.01 below the median UEF of the 39 high-draw gas tankless sets (0.96).
Certified as of October 27, 2026 · EPA ENERGY STAR data, public domain · Compare in the Heater finder
Size by size
| Rating set | Gas input, Btu/h | Max flow, gal/min | Share of heat ceiling | UEF | UEF rank | Therms/yr |
|---|---|---|---|---|---|---|
| Navien NPE-180A22 model numbers | 150,000 | 4.3 | 96% | 0.95 high | lowest of 39, 19 tied | 178 |
| Navien NPE-210A21 model number | 180,000 | 5.0 | 93% | 0.95 high | lowest of 39, 19 tied | 178 |
| Navien NPE-240A21 model number | 199,000 | 5.6 | 94% | 0.95 high | lowest of 39, 19 tied | 178 |
Share of heat ceiling: listed flow ÷ the flow the gas input could heat through 67 °F at 100% efficiency; test tolerances allow a little over 100%.
Navien NPE-xxA2: max flow against gas input
Max flow at a 67 °F rise, gal/min
Across the sizes
Moving from 150,000 Btu/h to 199,000 Btu/h of gas input lifts max flow from 4.3 gal/min to 5.6 gal/min, about 0.27 gal/min for each extra 10,000 Btu/h.
Strongest placings, size by size
| Measure | Value | Median of the group | Placing | Compared with |
|---|---|---|---|---|
| UEFNavien NPE-180A2 | 0.95 | 0.96 | lowest of 39, 19 tied | 39 high-draw gas tankless sets |
| Rated gas useNavien NPE-180A2 | 178 therms/yr | 176 therms/yr | highest of 39, 15 tied | 39 high-draw gas tankless sets |
| UEFNavien NPE-210A2 | 0.95 | 0.96 | lowest of 39, 19 tied | 39 high-draw gas tankless sets |
| Rated gas useNavien NPE-210A2 | 178 therms/yr | 176 therms/yr | highest of 39, 15 tied | 39 high-draw gas tankless sets |
| UEFNavien NPE-240A2 | 0.95 | 0.96 | lowest of 39, 19 tied | 39 high-draw gas tankless sets |
| Gas inputNavien NPE-240A2 | 199,000 Btu/h | 180,000 Btu/h | highest of 40, 13 tied | 40 gas tankless sets |
Model numbers
The line covers 4 model numbers under two brand names, all certified 2023-02-23.
| Model number | Brand | Rating set | Vent | Fuel | Min flow | Certified |
|---|---|---|---|---|---|---|
| NPE-180A2 | Navien | NPE-180A2 | Power Direct Vent | natural gas or propane | 1.00 gal/min | 2023-02-23 |
| VRP-150 | Vesta | NPE-180A2 | not listed | natural gas or propane | 0.50 gal/min | 2023-02-23 |
| NPE-210A2 | Navien | NPE-210A2 | Power Direct Vent | natural gas or propane | 1.00 gal/min | 2023-02-23 |
| NPE-240A2 | Navien | NPE-240A2 | Power Direct Vent | natural gas or propane | 1.00 gal/min | 2023-02-23 |
Nearest certified alternatives
| Rating set | Max flow | UEF | Gas input |
|---|---|---|---|
| Midea JSG40-24PCH-LPcompared with Navien NPE-180A2 | +0.1 gal/min | ±0.00 | same Btu/h |
| Midea MGWH150IXNNcompared with Navien NPE-180A2 | +0.1 gal/min | ±0.00 | same Btu/h |
| A. O. Smith ATM-140M-N 1compared with Navien NPE-180A2 | −0.2 gal/min | ±0.00 | −10,000 Btu/h |
| Bosch T9800 SE 160compared with Navien NPE-180A2 | +0.3 gal/min | ±0.00 | +10,000 Btu/h |
| Noritz NRCR92DV (GQ-C2660WXQ-FF US)compared with Navien NPE-210A2 | −0.1 gal/min | ±0.00 | −15,000 Btu/h |