Bosch Tronic 6100 C 27
#10 in ElectricFull review
For a two bathroom home in a warm climate that wants a compact whole home heater with a 2 year parts warranty, double what Rheem gives.
Amazon $636.60$636.60
The Bosch Tronic 6100 C 27 rates 3.1 among electric tankless water heaters; the Rinnai V53De rates 2.7 among gas ones. The Bosch Tronic 6100 C 27 costs $105.05 less ($636.60 vs $741.65).
Rinnai V53De
#19 in GasFull review
A low cost outdoor heater from a major brand for a small home, cabin or condo in a mild climate.
Amazon $741.65 Amazon $741.65$741.65
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.
Scores side by side
These two sit in different fuel classes (electric and gas), and each is scored against the reference points for its own class, so a rating says how well each does among its own fuel peers. How we rank explains each factor.
| Factor weight | Bosch Tronic 6100 C 27 | Rinnai V53De |
|---|---|---|
| Overall rating | 3.1/5 | 2.7/5 |
| Value 35% | 49 $23.58 per kW ($636.60, 27 kW) | 60 $6.18 per 1,000 BTU/h ($741.65, 120,000 BTU/h) |
| Heating power 25% | 64 27 kW | 0 120,000 BTU/h |
| Efficiency 15% | 38 0.93 UEF | 6 0.81 UEF |
| Warranty 25% | 29 5-year heat exchanger warranty | 50 10-year heat exchanger warranty |
Specifications
| Bosch Tronic 6100 C 27 | Rinnai V53De | |
|---|---|---|
| Heating | ||
| Fuel | Electric | Gas |
| Gas type | - | Natural gas or propane |
| Gas input | - | 15,500 to 120,000 BTU/h |
| Electric power | 27 kW | - |
| Max flow | 5.3 GPM | 5.3 GPM |
| UEF | 0.93 | 0.81 |
| Condensing | - | No |
| ENERGY STAR | - | No |
| Installation | ||
| Venting | - | Outdoor |
| Voltage | 240 V | - |
| Breakers | 120 A total | - |
| Weight | 14.8 lb | 29.7 lb |
| Features | ||
| Built-in recirculation | No | No |
| Wi-Fi | No | No |
| Heat exchanger warranty | 5 years | 10 years |
| Parts warranty | 2 years | 5 years |
| Released | 2023-01 | - |