Rinnai's Standard Limited Warranty on its SE+ Series tankless models covers material and workmanship defects for 15 years on the heat exchanger, 5 years on other parts, and 5 years on labor if you register within 90 days of installation, per Rinnai's SE+ Series Limited Warranty, dated October 2024. Miss registration and labor coverage drops to 1 year.
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That coverage applies specifically to the SE+ Series: the SENSEI RX and RXP models, and the SENSEI RU, RUR and RSC models, per the warranty document's own model list. Rinnai's other lines are not on that list. The non-condensing HE+ series and the REHP electric heat pump water heater, which stores 50, 65 or 80 gallons rather than heating on demand, point owners to separate warranty paperwork instead, per Rinnai's REHP and electric REHP models product pages, accessed August 2026.
Two details catch owners off guard. Coverage drops to 8 years or 12,000 operating hours, whichever comes first, if the temperature setting is left above 160°F, and the integrated controller itself carries only a 1-year warranty, separate from the rest of the unit, per the same document.
| Coverage | Residential term | Note |
|---|---|---|
| Heat exchanger | 15 years, or 12,000 operating hours, whichever comes first | Reduced to 8 years or 12,000 hours above a 160°F setting |
| Other parts and components | 5 years | |
| Labor | 5 years if registered within 90 days of installation | Defaults to 1 year without registration |
| Integrated controller | 1 year | Separate, shorter term than the rest of the unit |
Source: Rinnai, SE+ Series Limited Warranty, document 100000655(04), dated October 2024.
For the equipment and installed cost side of a Rinnai purchase, see the Rinnai tankless water heater cost guide.
A leaking heat exchanger on V and RL models usually first shows as code 79, Rinnai's leak detection code.
Rinnai's SE+ warranty excludes failures from improper installation like incorrect venting or a missing drain pan, improper maintenance like scale buildup or freeze damage, incorrect sizing, poor water quality, non-potable or chemically treated water, and any alteration or misuse, per Rinnai's SE+ Series Limited Warranty, dated October 2024.
All repairs must use genuine Rinnai parts and be carried out by, in the document's own words, a qualified professional who is properly trained to do the type of repair. A claim can also be denied if the part sent back to Rinnai is found free of defects, or damaged in return shipping, per the same document.
That exclusion list matters because several common tankless complaints, uneven temperature, a fault code, reduced flow, trace back to scale buildup, freezing, or a venting or water-quality issue rather than a factory defect. Those causes are explicitly carved out, so the repair bill can land on the owner even inside an otherwise active coverage window.
The same document also excludes closed-loop, space-heating-only installations and any unit with a defaced serial number or manufacture date, so a tankless water heater repurposed outside its intended use falls outside coverage regardless of age.
Vent blockage is excluded from Rinnai's warranty, which matters for code 10 airflow faults. Several causes of Rinnai code 12, including improper venting and incorrect gas pressure, fall under these exclusions. For a fan motor fault under warranty, see what Rinnai code 61 means and what the warranty pays.
Rinnai's own Find a PRO tool lets you search by ZIP code for installers and servicers, including a listed 'Rinnai ACE PRO' tier, per Rinnai, accessed August 2026. The SE+ warranty document adds three more paths: contact your place of purchase, contact Rinnai directly, or write to Rinnai's Georgia headquarters.
Rinnai's document is specific that repairs must be performed by a trained professional using genuine parts, so a warranty claim handled by an unauthorized installer with aftermarket parts risks denial. The locator does not label every listed company as warranty-authorized on its own, so for a warranty claim specifically, the phone number and mailing address above are the paths Rinnai's own document points to, separate from the general locator.
| Need | Where | Note |
|---|---|---|
| Find an installer or servicer | rinnai.us/find-pro, search by ZIP code | Filters include a 'Rinnai ACE PRO' tier |
| Warranty question, claim, or registration without internet access | Rinnai customer care line | Listed in the SE+ Limited Warranty document |
| Written correspondence | Rinnai America Corporation, 103 International Drive, Peachtree City, GA 30269 | Listed in the SE+ Limited Warranty document |
Source: Rinnai, SE+ Series Limited Warranty, dated October 2024; Rinnai, Find a PRO, accessed August 2026.
Rinnai's customer care line is staffed Monday through Friday, 8 a.m. to 8 p.m. Eastern, per Rinnai's residential FAQ page, accessed August 2026. The same number can register a product, check warranty status, or point you to a trained professional, per Rinnai's SE+ Series Limited Warranty document, dated October 2024.
Live chat runs the same weekday hours through Rinnai's website, per Rinnai's contact page, accessed August 2026. Rinnai's own FAQ states that error codes vary by product and directs owners to contact Rinnai or a local installer rather than publishing one universal fix, so support is where a model-specific display code gets an answer rather than a guess.
For a code-by-code breakdown of what a given display means on a Rinnai tankless unit, see the Rinnai tankless water heater repair guide. This page covers the warranty and support process around a repair, not the diagnostic codes themselves.
Rinnai's own residential FAQ does not publish a universal reset procedure, stating instead that error codes vary by product and directing owners to contact Rinnai or a local installer, per Rinnai, accessed August 2026. That matters because several excluded conditions, scale buildup, freeze damage, vent blockage, do not resolve with a reset and remain the owner's responsibility either way.
That is a deliberate gap, not an oversight: Rinnai's tankless line spans several series with different displays and different code sets, so one press-this-button answer would be wrong for some models. What stays constant across the warranty document is the line that decides who pays: a defect in materials or workmanship is covered, while scale, freezing, incorrect venting and poor water quality are not, no matter how many times the unit is power-cycled.
If a code clears and stays cleared, the SE+ document's repair standard still applies to anything that comes up later: genuine parts and a trained professional. For general guidance on which water heater problems call for a licensed professional versus routine upkeep, see the water heater problems hub. For Rinnai's specific error codes, the Rinnai tankless water heater repair guide covers that ground.
If the code that keeps returning is 11, the gas and ignition checks are laid out in what Rinnai code 11 means.
Every figure on this page is listed here with its publisher and, where the publisher states one, its date. If a number is not traceable to this list, it should not be treated as sourced.
Prices, phone hours and warranty terms change. Check these dates against today before treating a figure as current.
For SE+ Series condensing models, yes, for defects in materials or workmanship: 15 years on the heat exchanger, 5 years on other parts, and 5 years on labor if you register within 90 days of installation, per Rinnai's SE+ Series Limited Warranty, dated October 2024. Skip registration and labor coverage defaults to 1 year.
Improper installation, improper maintenance such as scale buildup or freeze damage, incorrect sizing, poor water quality, non-potable or chemically treated water, and any alteration or misuse, per Rinnai's SE+ Series Limited Warranty, dated October 2024. Repairs also require genuine Rinnai parts and a trained professional to keep coverage intact.
No. Registration is not required to validate the Limited Warranty itself, per Rinnai's SE+ Series Limited Warranty, dated October 2024. It only affects labor coverage: register within 90 days of installation for 5 years of labor coverage, or the default drops to 1 year without it.
Rinnai's Find a PRO tool searches by ZIP code for local installers and servicers, per rinnai.us, accessed August 2026. The SE+ warranty document also lists contacting Rinnai or your place of purchase as ways to reach a trained professional.
Rinnai's customer care line, per Rinnai's SE+ Series Limited Warranty document and Rinnai's residential FAQ page. The FAQ lists phone support Monday through Friday, 8 a.m. to 8 p.m. Eastern, accessed August 2026.
Rinnai's US lineup is gas tankless models plus the REHP electric heat pump water heater, which stores 50, 65 or 80 gallons, per Rinnai's residential and REHP product pages, accessed August 2026. There is no conventional gas or standard electric resistance tank model in Rinnai's current US residential lineup.
Independent Research
Published ranges for tank and tankless replacement, the failures that justify a repair, and the ones that do not. Sourced, dated, and free to read.
