EcoSmart ECOS 18
#14 in ElectricFull review
For a small home or apartment in a warm climate that wants whole house hot water on two breakers. Amazon stock was low when checked.
Amazon $449$449
2.6/5
For a small home or apartment in a warm climate that wants the Bosch name. Most buyers get more power for the money elsewhere.
- 18 kWHeating power
- 3.5 GPMMax flow
- 0.94UEF
- 5 yearsHeat exchanger warranty
Check price at Amazon$585.46
Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Modulating elements hold a steady outlet temperature
- Built in inlet filter protects the elements
- Touch controls with an LED display
Cons
- Costs more than 24 kW heaters from Stiebel and Rheem while giving less power
- Needs three breakers despite its modest output
The Bosch Tronic 6100 C family
Every Bosch Tronic 6100 C model we rank, smallest first. Ratings compare each against its own fuel.
| Model | Heating power | Rating | Price |
|---|---|---|---|
| Bosch Tronic 6100 C 18 (this one) | 18 kW | 2.6/5 | $585.46 |
| Bosch Tronic 6100 C 27 | 27 kW | 3.1/5 | $636.60 |
How it scores
The rating comes from 4 measured or published factors, each scored 0-100 against fixed reference points for its fuel. How we rank explains each one.
Specifications
| Model number | TR6100C-18 |
|---|---|
| Heating | |
| Fuel | Electric |
| Electric power | 18 kW |
| Max flow | 3.5 GPM |
| UEF | 0.94 |
| Installation | |
| Voltage | 240 V |
| Breakers | 90 A total |
| Weight | 14.8 lb |
| Features | |
| Built-in recirculation | No |
| Wi-Fi | No |
| Heat exchanger warranty | 5 years |
| Parts warranty | 2 years |
| Released | 2023-01 |
Alternatives in this fuel
Bosch Tronic 4000 C 10
#15 in ElectricFull review
For a busy kitchen sink or a pair of sinks that need more flow than a small point of use heater gives.
Amazon $251.99$251.99
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
Compare
Compare the Bosch Tronic 6100 C 18 with any other tankless water heater →
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