Brands

Noritz

A specialist rather than a full range manufacturer. Noritz makes gas tankless and nothing else, and it has built its current line around the specific job of replacing a storage tank. It also holds the strongest Central Valley parts position of the six brands we track, which matters more than most spec sheet differences on the day something fails.

Worth shortlisting if

You are converting a storage tank and the pipework is awkward
Local parts availability matters more to you than badge preference
Your existing gas line is 1/2 inch and upsizing looks expensive
You want the longest heat exchanger term in this set
You are replacing an existing Noritz unit

Look elsewhere if

A heat pump or a storage tank is the right technology for you
You want one manufacturer across several technologies
You will not keep up with annual descaling
You are adding a recirculation loop and want the 25 year term
Your gas service genuinely cannot support a tankless unit

What we have verified, and what we have not

Warranty terms, model lines and installer programmes change without notice, and they vary by model, registration and installation type. Rather than publish a number that quietly goes stale, each row shows its own state.

The Noritz brand record

Technologies made: Gas tankless only. No storage tanks, no heat pumps, no electric. If the right answer for your house is any of those, a preference for Noritz has to give way, and that is worth knowing before you get attached to the brand.
Source: Noritz residential product rangeChecked 7 Aug 2026
Tankless flow, by temperature rise: The EZ111 is rated 11.1 GPM at a 30°F rise. At a 60°F rise the same unit gives 6.5 GPM, at 70°F it gives 5.6 GPM and at 80°F it gives 4.9 GPM. A Central Valley winter asks for a 65°F to 75°F rise, which puts it between 5.3 and 6.1 GPM. The smaller EZ98 gives 5.7 GPM at a 60°F rise and the EZ71 gives 5.2 GPM.
Note what that means across the line. At the winter design condition the three models are much closer together than their headline numbers suggest, so paying up the range buys less than it looks like it does.
Source: Noritz EZ Series flow data by temperature riseChecked 7 Aug 2026
Retrofit design: The EZ Pro line is built around tank replacement: top mounted water connections so the existing pipework can often be met where it already is, field convertible between natural gas and propane, and indoor or outdoor configurations. Venting uses 2, 3 and 4 inch PVC or CPVC and approved systems, with flex vent retrofit supported using specified kits.
Source: Noritz EZ Series product documentationChecked 7 Aug 2026
Replacement bundles: EZTR40, EZTR50 and EZTR75 package the heater with specified vent and isolation hardware, positioned against 40, 50 and 75 gallon tanks respectively. That positioning is the manufacturer's, and it is not a substitute for sizing against what your household actually draws.
Source: Noritz EZTR bundle documentationChecked 7 Aug 2026
Warranty, EZ line residential: Without recirculation: 25 years heat exchanger, with a 15,000 burn hour cap. That is the longest heat exchanger term of any line in our set.
With controlled recirculation it drops to 15 years and a 12,000 hour cap. Adding a recirculation loop costs you ten years of cover, so decide on recirculation and on the brand in the same conversation rather than one after the other.
Parts 5 years, labour 1 year, on both configurations.
Where a burn hour cap applies, whichever limit arrives first is the one that counts. The detailed warranty document controls. Ask for the one covering the exact model you are quoted.
Source: Noritz warranty terms, EZ71, EZ98 and EZ111Checked 7 Aug 2026
If you want recirculation: The NRCR Pro line carries an integrated pump, and Noritz states support for a 1/2 inch loop up to 200 feet or a 3/4 inch loop up to 500 feet, subject to installation requirements. Treat it as the recirculation specific candidate rather than adding a loop to an EZ and losing the longer term.
Source: Noritz NRCR series documentationChecked 7 Aug 2026
Installer programme: PROCard Select and VIP. We found no blanket requirement that an installer hold a programme status, so treat it as a signal that the brand is serviced in an area rather than as a rule about who may fit it.
Source: Noritz PROCard and Contractor FinderChecked 7 Aug 2026
Local programme coverage: The deepest local coverage of the three tankless brands we cover. On our check date the Modesto area showed multiple installers and servicers, partner tenure labels, and at least one company carrying an explicit Noritz trained designation. Combined with the parts position below, that is the strongest argument on this page. We do not publish company names, because a directory entry is a snapshot and a listing is not a recommendation from us.
We will not describe any installer as authorised, certified or trained except where that exact status appears in the manufacturer’s own current directory, and we do not introduce homeowners to companies on the strength of a directory listing alone.
Parts availability, Central Valley: Strong, and the best of the six brands we track. PACE Supply in Ripon appears in the manufacturer directory, and Noritz's own support store shows active genuine parts inventory. On a brand that lives or dies on how fast a part arrives, this is the row that matters most.
Source: Noritz contractor directory and parts storeChecked 7 Aug 2026
Consumer financing: None found at manufacturer level. Any payment plan on a Noritz quote will be your installer's own arrangement, so compare it on its own terms rather than treating it as a manufacturer benefit.
Source: Noritz public product and programme pagesChecked 20 Aug 2026
Known failure modes: Noritz documents Code 90 as a combustion or airflow abnormality. On a new installation it points at gas supply, venting, condensate and configuration. On an established unit it also points at dirt, maintenance and condensate blockage. Noritz itself hedges on cause, and we will not turn a diagnostic code into a reliability claim about the brand.
Source: Noritz Code 90 knowledge base articleChecked 7 Aug 2026

Noritz or Rinnai

The research does not name an overall winner between these two, and neither will we. It splits on what the hard part of your job actually is.

Noritz when the retrofit geometry is the problem: top mounted connections, flex vent compatibility, bundled replacement kits and the deepest local parts and service coverage in the set. Rinnai when the RX or RXP meets your design flow and the recirculation feature set or the local service path matters more than how the pipework lands.

And if you are still deciding whether tankless is right at all, that is the question to settle first. We have a page arguing the other side, which is worth reading before you shortlist any brand on this page.

Ask your installer these before committing to the brand

Will this run on my existing gas line, or does it need upsizing?
What flow does this model give at my winter design rise?
Does my recirculation choice change the warranty term?
How many of these have you installed in the last year?
Are parts held locally, or ordered in?
Would you put this brand in your own house, and why?

Check whether tankless is right first Compare all brands