Rinnai Sensei RX160i
#12 in GasFull review
A very efficient heater for a two bathroom home that does not need the full 199,000 BTU/h of the RX199i.
Amazon $1,298.43$1,298.43
The Rinnai Sensei RX160i is the better tankless water heater overall, rated 3.8 to 3.4. The Rinnai Sensei RX160i leads on efficiency. The ThermoMate RTC68iN wins on value. The ThermoMate RTC68iN costs $198.44 less ($1,099.99 vs $1,298.43).
ThermoMate RTC68iN
#15 in GasFull review
A budget condensing heater for natural gas homes that want PVC venting and lower gas bills, if you can live with an unclear warranty.
ThermoMate $1,099.99$1,099.99
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 Rinnai Sensei RX160i for efficiency (0.97 UEF vs 0.91 UEF).
- Choose the ThermoMate RTC68iN for value ($6.75 per 1,000 BTU/h ($1,099.99, 163,000 BTU/h) vs $8.12 per 1,000 BTU/h ($1,298.43, 160,000 BTU/h)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every gas tankless water heater; a clear win is highlighted. How we rank explains each one.
| Factor weight | Rinnai Sensei RX160i | ThermoMate RTC68iN |
|---|---|---|
| Overall rating | 3.8/5 | 3.4/5 |
| Value 35% | 36 $8.12 per 1,000 BTU/h ($1,298.43, 160,000 BTU/h) | 52 $6.75 per 1,000 BTU/h ($1,099.99, 163,000 BTU/h) |
| Heating power 25% | 51 160,000 BTU/h | 54 163,000 BTU/h |
| Efficiency 15% | 100 0.97 UEF | 69 0.91 UEF |
| Warranty 25% | 100 15-year heat exchanger warranty | 50 heat exchanger warranty not published (neutral score used) |
Specifications
| Rinnai Sensei RX160i | ThermoMate RTC68iN | |
|---|---|---|
| Heating | ||
| Fuel | Gas | Gas |
| Gas type | Natural gas or propane | Natural gas |
| Gas input | 15,000 to 160,000 BTU/h | 163,000 BTU/h |
| Max flow | 9 GPM | 9.4 GPM |
| UEF | 0.97 | 0.91 |
| Condensing | Yes | Yes |
| ENERGY STAR | Yes | - |
| Installation | ||
| Venting | Both | Indoor |
| Vent type | 2 in or 3 in PVC/CPVC/PP, or concentric | PVC |
| Weight | 54 lb | 50 lb |
| Features | ||
| Built-in recirculation | No | No |
| Wi-Fi | No | No |
| Heat exchanger warranty | 15 years | - |
| Parts warranty | 5 years | - |