Schedule 559-770-9772
Rinnai PRO — Fresno, CA

Rinnai Water Heater
Repair & Installation

Certified Rinnai PRO technicians serving Fresno and the Central Valley. Factory-trained on all Rinnai tankless models — SENSEI RX, RUR, RL, and RLX series.

Rinnai Water Heater Service in Fresno, CA

Rinnai tankless water heater installation and repair in Fresno CA

Rinnai is the #1 selling brand of tankless gas water heaters in North America — and for good reason. Rinnai tankless units are known for reliability, efficiency, and advanced technology that delivers endless hot water on demand. When your Rinnai needs installation, repair, or maintenance in Fresno or the Central Valley, you want a technician who truly knows the platform. Stedman's Plumbing is a certified Rinnai PRO, meaning our technicians have completed Rinnai's official Level II Installation and Level III Service training programs and are listed on rinnai.us as verified PRO contractors.

That certification matters for your wallet and your warranty. Rinnai requires that installation and service be performed by a trained professional for the manufacturer's warranty to remain fully intact. Our PRO status also means we have direct access to Rinnai's priority tech support line, OEM diagnostic tools, and factory knowledge of every platform — including the newest SENSEI RX. One issue Fresno homeowners face more than most: the LC code (scale buildup from hard water), which is the single most common Rinnai service call in the Central Valley. We know it inside and out, and we carry the equipment to resolve it the same day.

What It Means to Be a Rinnai PRO

  • ✓ Completed Rinnai Level II Installation + Level III Service Training
  • ✓ Factory-trained on SENSEI RX, RUR, RL, and RLX platforms
  • ✓ Listed on rinnai.us/find-pro as a verified Rinnai PRO
  • ✓ Authorized for warranty registration and warranty claims
  • ✓ Access to Rinnai's priority PRO tech support line
  • ✓ Rinnai requires PRO installation for full warranty to apply

Rinnai Models We Install & Service

We service the full current Rinnai lineup, from the flagship SENSEI RX condensing series to the proven RL non-condensing platform. Every model gets the same factory-trained attention.

SENSEI RX Series

Up to 0.98 UEF · 11 GPM

Rinnai's most efficient condensing unit. Features Smart Connect™ app compatibility, Versa Vent™ flexible installation, and recirculation-ready design. Ideal for large homes or high-demand households.

SENSEI RXP Series

Built-in Smart-Circ™ Pump

All the performance of the SENSEI RX with a factory-integrated Smart-Circ™ recirculation pump — delivering near-instant hot water to every fixture without a dedicated return line.

RUR Series

0.93 UEF · Built-in Recirc · Wi-Fi

Condensing, Ultra Low NOx, with built-in recirculation and Wi-Fi monitoring. A versatile whole-home solution with strong efficiency ratings, available in multiple BTU outputs.

RUS / RUCS Series

High Output · 6 Simultaneous Fixtures

Condensing series engineered for high-demand applications — large homes with multiple bathrooms running simultaneously. Available in concentric and twin-pipe venting configurations.

RL / RLX Series

Non-Condensing · Ultra Low NOx · Wi-Fi

Rinnai's proven non-condensing platform with HE+ efficiency, Wi-Fi monitoring capability, and Ultra Low NOx burner technology. A reliable workhorse for whole-home hot water.

Common Rinnai Issues We Fix

Rinnai's self-diagnostic error codes make troubleshooting straightforward — if you know what you're looking at. Our technicians are trained on every current Rinnai code and carry common OEM parts to resolve most issues in a single visit.

LC Code / Code 00 — Scale Buildup

The #1 Rinnai service call in Fresno. The LC counter (LC0–LC9) tracks heat exchanger scale from hard water. It will not reset on its own — a full descale flush is required. At LC9 the unit locks out entirely.

Code 11 — Ignition Failure

Unit attempts to ignite but fails to establish a flame. Common causes include gas supply issues (pressure, shut-off valve), a fouled igniter, or a failed gas solenoid valve.

Code 12 — Flame Failure

Flame ignites but does not sustain. Often caused by a contaminated flame rod, carbon buildup on the burner, or a faulty solenoid. More common after extended periods of low-use.

Code 65 — Flow Turbine / Flow Sensor

The flow turbine or sensor is not reading correctly. Usually caused by debris lodged in the turbine assembly, a worn impeller bearing, or a failed sensor — unit will not activate without flow signal.

Code 79 — Heat Exchanger Overheat

Thermal protection has tripped due to severe scale restriction on the heat exchanger. Nearly always associated with a high LC counter. A full descale is required — do not reset and ignore.

Code 32 — Temperature Sensor Fault

The outgoing water temperature sensor has failed or is reading out of range. Can cause temperature instability or unit shutdown. Sensor replacement resolves most cases.

The LC Code & Fresno Hard Water

⚠ Why Fresno Hard Water Is a Rinnai's Biggest Enemy

Fresno's municipal water supply draws from the Sierra Nevada snowpack and local groundwater — both carrying significant dissolved calcium and magnesium. Fresno water typically measures 200–300+ mg/L as CaCO3, placing it firmly in the "very hard" category. Every gallon that passes through your Rinnai's heat exchanger deposits a microscopic layer of mineral scale.

Rinnai's LC counter quietly tracks this accumulation. LC0 is a new unit. LC9 means the unit will lock out and refuse to operate. Critically, the counter does not reset automatically — the scale must be physically flushed out with a descaling solution before the counter resets.

We recommend annual descaling for all Rinnai tankless units in Fresno. Skipping this service doesn't just risk lockout — scale on the heat exchanger forces the unit to work harder, increasing gas consumption and shortening lifespan. It can also jeopardize warranty coverage, as Rinnai's warranty terms require proper maintenance.

Stedman's full Rinnai descale process includes: isolating the unit from the water supply, connecting a recirculation pump and food-grade white vinegar or citric acid solution, flushing the heat exchanger for 45–60 minutes, purging with fresh water, resetting the LC counter, and a full operational test. We also inspect the inlet filter screen and clean the combustion air intake as part of the service visit.

Rinnai Warranty — Why Certification Matters

Rinnai offers one of the strongest warranties in the tankless water heater industry — but maximizing that coverage requires proper installation and registration by a qualified professional. As a certified Rinnai PRO, Stedman's Plumbing registers your warranty on your behalf and is authorized to process warranty claims directly with Rinnai.

Component Standard Coverage With PRO Registration (within 90 days)
Heat Exchanger 12 years 15 years
Parts 5 years 5 years
Labor 1 year Up to 5 years (select models)

Important: Rinnai states that installation must be performed by a trained professional for the full warranty to apply. Using an unlicensed or uncertified technician can void warranty coverage entirely — particularly for costly heat exchanger claims. Stedman's is a verified Rinnai PRO and handles all warranty paperwork for you.

Our Rinnai Service Process

1
Diagnostic Assessment We read all active and stored error codes, inspect the unit's combustion, venting, gas pressure, and flow rate — giving you a full picture before any repair begins.
2
Upfront Flat-Rate Quote No surprises. We explain what's needed and provide a written flat-rate price before touching anything. You approve the work before we proceed.
3
OEM Repair or PRO Installation We use factory OEM parts for all Rinnai repairs. Installations follow Rinnai's published commissioning specs — gas pressure, flow rates, temperature settings — exactly as required for warranty compliance.
4
Warranty Registration & Documentation For new installations, we register your warranty with Rinnai on the spot — ensuring your heat exchanger and parts coverage is maximized from day one.
5
Maintenance Plan & Walk-Through We walk you through the unit's controls and Wi-Fi app setup (where applicable), explain what the LC counter means, and schedule your first annual descaling visit so you never have to worry about it.

Frequently Asked Questions

What is a Rinnai PRO and why does it matter?
A Rinnai PRO is a plumbing contractor who has completed Rinnai's factory training — Level II Installation and Level III Service — and is listed on rinnai.us as a verified PRO. Rinnai requires PRO installation for the full manufacturer warranty to apply. PRO technicians also have access to Rinnai's priority tech support line and OEM diagnostic resources, meaning faster, more accurate repairs. Stedman's Plumbing is a certified Rinnai PRO serving Fresno and the Central Valley.
My Rinnai shows the LC code — what should I do?
The LC code indicates scale buildup on the heat exchanger from hard water minerals. It will not reset on its own — the unit must be physically flushed (descaled) by a qualified technician. In Fresno's hard water, ignoring the LC code leads to LC9 lockout or Code 79 overheat. Call Stedman's at 559-770-9772 to schedule a same-day descaling service.
How often does a Rinnai need to be descaled in Fresno?
Fresno's water is classified as very hard (typically 200–300+ mg/L as CaCO3). Rinnai recommends annual descaling for hard water areas. Most Central Valley units benefit from a flush every 12 months to maintain efficiency, prevent LC lockout, and keep the warranty intact. We offer annual maintenance plans to take care of this automatically.
Do you install the new Rinnai SENSEI RX series?
Yes. Stedman's Plumbing is factory-trained on the SENSEI RX and RXP platforms. We stock common SENSEI RX accessories including the Smart-Circ recirculation kit and can complete most SENSEI installations same-day or next-day throughout Fresno and the surrounding Central Valley.
Will using a non-Rinnai technician void my warranty?
Rinnai's warranty terms require that installation and service be performed by a trained professional. Using an uncertified technician can jeopardize your warranty coverage — particularly for heat exchanger claims, which are the most valuable part of the warranty at 12–15 years. Stedman's is a verified Rinnai PRO and is authorized to perform warranty installations, registrations, and claims on your behalf.

Rinnai Not Heating Water?

Certified Rinnai PRO — factory-trained technicians, same-day service available in Fresno and the Central Valley. Lic. #1110490.

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