Bosch Tronic 6100 C 18
#16 in ElectricFull review
For a small home or apartment in a warm climate that wants the Bosch name. Most buyers get more power for the money elsewhere.
Amazon $585.46$585.46
The Bosch Tronic 6100 C 18 and the Stiebel Eltron Tempra 15 Plus are evenly matched, rated 2.6 and 2.6. The Bosch Tronic 6100 C 18 leads on value and heating power. The Stiebel Eltron Tempra 15 Plus wins on warranty and efficiency. The Bosch Tronic 6100 C 18 costs $33.54 less ($585.46 vs $619).
Stiebel Eltron Tempra 15 Plus
#17 in ElectricFull review
For a small home or cabin on a 100 A service in a warm climate where a steady shower temperature matters more than flow. Homes with more service get more for the money from a Trend model.
Amazon $619$619
Prices 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 Bosch Tronic 6100 C 18 for value ($32.53 per kW ($585.46, 18 kW) vs $42.99 per kW ($619, 14.4 kW)) and heating power (18 kW vs 14.4 kW).
- Choose the Stiebel Eltron Tempra 15 Plus for warranty (7-year heat exchanger warranty vs 5-year heat exchanger warranty) and efficiency (0.96 UEF vs 0.94 UEF).
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 | Bosch Tronic 6100 C 18 | Stiebel Eltron Tempra 15 Plus |
|---|---|---|
| Overall rating | 2.6/5 | 2.6/5 |
| Value 35% | 25 $32.53 per kW ($585.46, 18 kW) | 3 $42.99 per kW ($619, 14.4 kW) |
| Heating power 25% | 28 18 kW | 14 14.4 kW |
| Efficiency 15% | 50 0.94 UEF | 75 0.96 UEF |
| Warranty 25% | 29 5-year heat exchanger warranty | 57 7-year heat exchanger warranty |
Specifications
| Bosch Tronic 6100 C 18 | Stiebel Eltron Tempra 15 Plus | |
|---|---|---|
| Heating | ||
| Fuel | Electric | Electric |
| Electric power | 18 kW | 14.4 kW |
| Max flow | 3.5 GPM | 3 GPM |
| UEF | 0.94 | 0.96 |
| Installation | ||
| Voltage | 240 V | 240 V |
| Breakers | 90 A total | 60 A total |
| Weight | 14.8 lb | 16.1 lb |
| Features | ||
| Built-in recirculation | No | No |
| Wi-Fi | No | No |
| Heat exchanger warranty | 5 years | 7 years |
| Parts warranty | 2 years | 3 years |
| Released | 2023-01 | - |