For adding fast hot water to a far sink or a single shower in a warm climate. The long warranty sets it apart from cheaper point of use units.
Amazon $266.14The Stiebel Eltron DHX 12-2 Trend is the better tankless water heater overall, rated 3.1 to 2.5. The Stiebel Eltron DHX 12-2 Trend leads on efficiency and value. The Bosch Tronic 4000 C 8 costs $37.14 less ($229 vs $266.14).
For instant hot water at a kitchen or bathroom sink far from the main heater.
Amazon $229Prices were last checked October 31, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Stiebel Eltron DHX 12-2 Trend for efficiency (0.96 UEF vs 0.92 UEF) and value ($22.18 per kW ($266.14, 12 kW) vs $26.94 per kW ($229, 8.5 kW)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every electric tankless water heater; a clear win is highlighted. How we rank explains each one.
| Factor weight | Stiebel Eltron DHX 12-2 Trend | Bosch Tronic 4000 C 8 |
|---|---|---|
| Overall rating | 3.1/5 | 2.5/5 |
| Value 35% | 54 $22.18 per kW ($266.14, 12 kW) | 39 $26.94 per kW ($229, 8.5 kW) |
| Heating power 25% | 4 12 kW | 0 8.5 kW |
| Efficiency 15% | 75 0.96 UEF | 25 0.92 UEF |
| Warranty 25% | 57 7-year heat exchanger warranty | 50 heat exchanger warranty not published (neutral score used) |
Specifications
| Stiebel Eltron DHX 12-2 Trend | Bosch Tronic 4000 C 8 | |
|---|---|---|
| Heating | ||
| Fuel | Electric | Electric |
| Electric power | 12 kW | 8.5 kW |
| Max flow | 2.5 GPM | 1.6 GPM |
| UEF | 0.96 | 0.92 |
| Installation | ||
| Voltage | 240 V | 240 V |
| Breakers | 50 A total | 40 A total |
| Weight | 5.5 lb | 4.4 lb |
| Features | ||
| Built-in recirculation | No | No |
| Wi-Fi | No | No |
| Heat exchanger warranty | 7 years | - |
| Parts warranty | 3 years | - |
| Released | - | 2023-01 |
