Condensing tankless · Gas / Propane
SENSEI RX Series
The SENSEI RX is Rinnai's top condensing tankless water heater. It heats water only as it is drawn, so hot water is effectively unlimited, and its condensing heat exchanger recovers heat from the exhaust that a non-condensing unit sends outside — which is how it reaches up to 0.98 UEF. Four sizes (RX130 through RX199, roughly 130,000 to 199,000 BTU/h) cover everything from a small home to a large one with several bathrooms running at once.
Condensing efficiency, endless hot water
A tankless heater has no standby tank to keep hot, so it wastes little energy between draws and takes up about the space of a carry-on suitcase on the wall. The RX's secondary condensing heat exchanger pulls extra heat out of the flue gases, cutting fuel use and letting it vent in inexpensive PVC or CPVC rather than stainless.
Because output modulates, the burner throttles down for a single hand-wash and up for a shower plus a dishwasher, holding the set temperature steady the whole time.
