High-efficiency gas heaters that recover heat from the exhaust and vent through PVC.
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.
Best Condensing Tankless Water Heaters: Gas
- Rinnai Sensei RX199i#1 of 7Full review
A top choice for a large home that wants one heater for three or more showers at once with the lowest gas bills Rinnai offers.
Amazon $1,532.79$1,532.79199,000 BTU/h11 GPM0.98 - Rheem RTGH-95DV#2 of 7Full review
A well priced condensing whole home heater for buyers who want PVC venting and lower gas bills.
Amazon $1,411.70 Amazon $1,411.99$1,411.70199,900 BTU/h9.5 GPM0.93 - Rheem IKONIC S11i#3 of 7Full review
A premium condensing heater for a large home that wants top efficiency and app control from one unit.
Amazon $1,847.43 Amazon $1,859.99$1,847.43199,900 BTU/h11.2 GPM0.96 - Rinnai Sensei RX160i#4 of 7Full 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$1,298.43160,000 BTU/h9 GPM0.97 - A.O. Smith Adapt ATHR-199M#5 of 7Full review
A premium whole home heater for buyers who want built in recirculation and top efficiency and can pay for it.
Amazon $2,346.08$2,346.08199,000 BTU/h10.5 GPM0.95 - ThermoMate RTC68iN#6 of 7Full 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$1,099.99163,000 BTU/h9.4 GPM0.91 - Noritz NRC661-DV#7 of 7Full review
A compact condensing heater for a smaller home that wants PVC venting, though bigger rivals cost little more.
Amazon $1,280.09 Amazon $1,470.40$1,280.09120,000 BTU/h6.6 GPM0.89
