EcoSmart ECO 8
#8 in ElectricFull review
For a faucet far from the main water heater. A lifetime warranty at a low price makes it a safe point of use pick if you hire the install out.
Amazon $219$219
The EcoSmart ECO 8 is the better tankless water heater overall, rated 3.2 to 2.5. The EcoSmart ECO 8 leads on efficiency. The EcoSmart ECO 8 costs $10 less ($219 vs $229).
Bosch Tronic 4000 C 8
#18 in ElectricFull review
For instant hot water at a kitchen or bathroom sink far from the main heater.
Amazon $229$229
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 EcoSmart ECO 8 for efficiency (0.96 UEF vs 0.92 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 | EcoSmart ECO 8 | Bosch Tronic 4000 C 8 |
|---|---|---|
| Overall rating | 3.2/5 | 2.5/5 |
| Value 35% | 38 $27.38 per kW ($219, 8 kW) | 39 $26.94 per kW ($229, 8.5 kW) |
| Heating power 25% | 0 8 kW | 0 8.5 kW |
| Efficiency 15% | 75 0.96 UEF | 25 0.92 UEF |
| Warranty 25% | 100 limited lifetime heat exchanger warranty | 50 heat exchanger warranty not published (neutral score used) |
Specifications
| EcoSmart ECO 8 | Bosch Tronic 4000 C 8 | |
|---|---|---|
| Heating | ||
| Fuel | Electric | Electric |
| Electric power | 8 kW | 8.5 kW |
| Max flow | 2 GPM | 1.6 GPM |
| UEF | 0.96 | 0.92 |
| Installation | ||
| Voltage | 240 V | 240 V |
| Breakers | 40 A total | 40 A total |
| Weight | 4.8 lb | 4.4 lb |
| Features | ||
| Built-in recirculation | No | No |
| Wi-Fi | No | No |
| Heat exchanger warranty | Limited lifetime | - |
| Released | - | 2023-01 |