Every replacement below is a published model with verified specs. Savings calculated from EIA average energy prices.
Quick verdict
Fewest install changes
Rheem RTGH-95DVLN-3
no detected install changes
Lowest annual bill
Bradford White RE2HP50-1NCTT
$144/yr
Shortest unit
Rheem RTGH-95DVLN-3
23.0" tall
Your T-H3J-OS-N-1 costs $242/yr. Every option below cuts that bill. See all condensing tankless models
What your current unit costs to operate
Annual$242/yr
10-year projection$2,420
Based on U.S. average energy rates (EIA). UEF 0.95.
Replacement options
Navien NPE-240S2
Condensing TanklessUEF 0.96 / ~$239/yr
UEF 0.96 vs 0.95, Wi-Fi included, taller at 27.4 vs 22.5 inches
Annual savings$3/yr
10-year savings$30
Install changes
- 15A dedicated breaker needed
- Different venting: direct vent (currently power vent)
- 4.9" taller than your current unit
Rheem RTGH-95DVLN-3
Condensing TanklessUEF 0.93 / ~$250/yr
UEF 0.93 vs 0.95, similar size at 23 vs 22.5 inches tall
Operating cost is similar to your current unit ($8/yr more).
Install changes
- No venting required (your current unit has a vent)
Rheem PROPH50 T2 RH400-30
Heat PumpUEF 3.88 / ~$146/yr / 10-yr tank warranty
Switch to heat pump, UEF jumps from 0.95 to 3.88, requires tank space and 240V
Annual savings$96/yr
10-year savings$960
Install changes
- Requires 240V (your current unit is 120V)
- 30A dedicated breaker needed
- No venting required (your current unit has a vent)
- 39.2" taller than your current unit
- 4.5" wider than your current unit
Bradford White RE2HP50-1NCTT
Heat PumpUEF 3.89 / ~$144/yr / 10-yr tank warranty
Switch to heat pump, UEF jumps from 0.95 to 3.89, compact 46.1-inch height
Annual savings$98/yr
10-year savings$980
Install changes
- Requires 240V (your current unit is 120V)
- No venting required (your current unit has a vent)
- 23.6" taller than your current unit
Side by side, the key differences.
Replacement comparison
| Spec | Your unit | NPE-240S2 | RTGH-95DVLN-3 | PROPH50 T2 RH400-30 | RE2HP50-1NCTT |
|---|---|---|---|---|---|
| UEF | 0.95 | 0.96 | 0.93 | 3.88 | 3.89 |
| Annual Cost | $242/yr | $239/yr | $250/yr | $146/yr | $144/yr |
| Annual Savings | $3/yr | $-8/yr | $96/yr | $98/yr | |
| Height | 22.5" | 27.4" | 23" | 61.8" | 46.1" |
| Width | 17.8" | 17.3" | 18" | 22.2" | 18.0" |
| Warranty | — | — | 10 yr | 10 yr |
● Best value in each row. Your unit column shows the model being replaced.
Common install considerations for gas tankless units
What is required depends on your existing installation, local code, and installer preference.
The federal tax credit of up to $2,000 under IRA Section 25C expired December 31, 2025. State and utility rebates may still apply.
Related
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Sources. ENERGY STAR, manufacturer spec sheets, EIA average energy prices.Methodology