How Long Does a Rinnai Tankless Water Heater Last?

Up to 20 years, according to Rinnai. Water quality, how much you use it and yearly flushing all affect that number.

Does a Rinnai Tankless Water Heater Work in a Power Outage?

No. Rinnai says its tankless units won't run without power, though an optional battery backup can keep one going during an outage.

Can a Rinnai Be Installed Outside?

Yes, every SENSEI RX model can go indoors or outdoors. Outdoor installs use Rinnai's Versa Vent cap.

Do I Have to Register My Rinnai?

Registration within 90 days raises labor coverage from 1 year to 5 years. The 15-year heat exchanger and 5-year parts coverage apply either way.

Will a Rinnai Run on Propane?

Yes. SENSEI RX models run on natural gas or propane, and Rinnai says its Smart Sense valve adjusts without a conversion kit.

Rinnai Water Heaters on Long Island

Water Heater Brand

About Rinnai Water Heaters

We install, repair and service Rinnai water heaters, and we stock the common parts. We've been a family company since 1981, licensed and insured, and the estimate costs you nothing.

Rinnai was founded in Japan in 1920 and set up North American operations in 1974, with a distribution, research and training center in Peachtree City, Georgia. It says it was the first major tankless brand assembled in the U.S.A. and that more homeowners pick Rinnai than any other tankless brand.

Tankless is the core of the business. Rinnai's residential lineup also includes the REHP electric heat pump water heater and the I-SERIES Plus condensing boilers, which come in 6 heat-only and 8 combi models according to Rinnai's product page. Rinnai recommends professional installation for all of them.

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All Models Serviced

Model Lineup

Rinnai Water Heater Models We Install and Service

Series	Key Ratings	Good For
SENSEI RX (RX130iN to RX199iN)	Condensing, up to 0.98 UEF; RX199iN 15,000 to 199,000 BTU, 11.1 GPM	Whole-house hot water, indoors or outdoors
SENSEI RXP (RXP160i, RXP199i)	Condensing, 0.98 UEF, built-in pump with Smart-Circ recirculation	Homes where you wait at the tap for hot water
RUS and RUCS	Condensing, 0.90 and 0.85 UEF	Replacing an older Rinnai condensing unit
RE and REP (non-condensing)	0.81 and 0.82 UEF; RE199iN 10,400 to 199,000 BTU, indoor	Small to mid-sized homes on a budget
REHP50, REHP65, REHP80 (heat pump)	Up to 4.0 UEF, up to 91-gal first hour, runs on 37°F to 109°F air	All-electric homes
I-SERIES Plus (IP combi and solo)	96% AFUE, four built-in zones, outdoor reset	One unit for heat and hot water on gas

Long Island Homes

Rinnai Water Heaters for Long Island Homes

A Rinnai tankless unit needs a gas supply sized for up to 199,000 BTU, which is far more than a 40,000 BTU tank burner. Many Long Island homes need a larger gas line or meter for that, and we check it before quoting. If you heat with oil and have no gas, the REHP heat pump or an indirect tank off your boiler usually makes more sense.

Every SENSEI RX model installs indoors or outdoors, and Rinnai's Versa Vent cap adapts the unit for outdoor mounting. On the South Shore and near the water, we look at where salt spray and snow drifts hit before choosing an outside wall.

Hard water is the other Long Island issue. Rinnai's FAQ says to flush mineral deposits at least once a year, more often with harder water, and its warranty drops heat exchanger coverage to 8 years if the temperature is set above 160°F. If you're all-electric and lean toward the REHP heat pump model, ask us whether it's on PSEG Long Island's qualified list, since the 2026 rebate reaches $1,200.

Warranty

Rinnai Water Heater Warranty

The SENSEI residential warranty covers the heat exchanger for 15 years or 12,000 operating hours, whichever comes first, and all other parts for 5 years. Reasonable labor is covered for 1 year, or 5 years if the unit is registered within 90 days.

Two rules can cost you coverage. Rinnai won't honor the warranty on units bought from an unapproved online seller, and it says improper installation may void it. Units in closed loop setups aren't covered either. We register it on Rinnai's site for you after the install.

On top of the manufacturer's coverage, Domino backs every installation with a 1-year labor warranty.

Compare Brands

Rinnai vs Navien Water Heaters

Both brands build condensing tankless units, and the specs are close. Rinnai's SENSEI RX lists up to 0.98 UEF, and the RX199iN delivers 11.1 GPM. Navien's NPE-S2 lists up to 0.96 UEF and 15:1 turndown, and its NPE-A2 adds a buffer tank and pump it calls ComfortFlow. Rinnai's answer to built-in recirculation is the RXP with Smart-Circ, which learns when you use hot water.

Warranties line up at 15 years on the heat exchanger for both. Rinnai caps that at 12,000 operating hours, while Navien cuts it to 5 years if an outside recirculation pump runs nonstop. Rinnai's labor coverage jumps to 5 years with registration; Navien lists 1 year. Compare all the makes we work on at our water heater brands page.

Repair & Service

Rinnai Water Heater Repair and Service

We stock common Rinnai parts such as inlet filters, igniters and sensors, and we carry the pump kit for a yearly descaling flush. Book water heater repair for any of these.

Error code on the display: the unit is reporting a fault, often ignition, gas supply or venting, and the code points us to it.
Hot water turns cold mid-shower: flow dropped below the minimum to fire, or scale is choking the heat exchanger.
Water takes too long to get hot: long pipe runs with no recirculation, or a recirc pump that's off schedule.
White cloud from the vent in winter: that's normal water vapor from a condensing unit, according to Rinnai.
Unit dead after a storm: power was lost, or a surge damaged the control board.
Lower flow than before: the inlet water filter screen is clogged.

Installation

Rinnai Water Heater Installation and Replacement

Price depends on the model, gas line or meter upgrades, venting length, removing the old tank, and adding recirculation. Call for a quote. Our tankless water heater page covers the tank-to-tankless switch in more detail.

We count your fixtures and peak use to size the unit by GPM and winter water temperature.
We check the gas meter and line size, power, and the venting route.
You get a written quote that names the Rinnai model and any gas line work.
We mount the unit, run the vent, install isolation valves for future flushing, and pipe the condensate drain.
We fire it, test flow at several taps, and register it within 90 days.

Rinnai Water Heater Installation and Repair on Long Island