Tankless Water Heater Repair & Flush
Specialists in Rinnai, Noritz, and Navien systems. Annual flush and diagnostic services help prevent scale buildup and maintain reliable performance.
Professional Tankless Water Heater Repair & Flush in Orange County
Tankless water heaters are built to last 15-20+ years, but they need regular maintenance to perform at their best. The most important service is annual descaling — flushing the heat exchanger with a descaling solution to remove mineral buildup. In Orange County, where water hardness averages 15-25 grains per gallon, scale accumulates faster than in many other regions.
KCB Plumbing provides factory-certified service for Rinnai, Noritz, and Navien tankless water heaters. Our technicians are trained on the specific diagnostic procedures, error codes, and repair techniques for each brand. Whether your unit is displaying an error code, producing inconsistent temperatures, or has reduced flow, we can diagnose and fix the issue.
Common tankless water heater problems include ignition failure, flame rod fouling, scale buildup in the heat exchanger, flow sensor issues, and venting problems. Many of these can be prevented with annual maintenance. We offer a comprehensive flush and inspection service that keeps your tankless system running efficiently and extends its lifespan.
Need Tankless Water Heater Repair & Flush?
Call for a free over-the-phone estimate. Upfront pricing, no surprises.
(714) 894-6520Our Process
How It Works
Diagnostic Check
We check for error codes, test the ignition sequence, and inspect all connections.
Descaling Flush
We circulate a food-grade descaling solution through the heat exchanger for 45-60 minutes to dissolve mineral buildup.
Component Inspection
We inspect the burner assembly, flame rod, flow sensor, inlet filter, and venting system.
System Test
We run the unit through multiple cycles, checking temperature accuracy, flow rate, and ignition reliability.
Performance Report
You receive a summary of what we found, what we serviced, and any recommendations for parts or future attention.
Why Choose KCB for Tankless Water Heater Repair & Flush
- Upfront flat-rate pricing — you approve before we start
- Licensed (#604044), insured, and bonded
- 99.9% on-time guarantee
- 4.9 stars across 50+ Google reviews
- 27+ years serving Orange County
- Workmanship guarantee on all repairs and installations
What Affects Pricing
We provide transparent, upfront pricing before any work begins. Here are the factors that affect the cost of tankless water heater repair & flush:
- Type of service (flush only, repair, or both)
- Brand and model of tankless unit
- Parts needed for any repairs
- Whether isolation valves need to be installed (for units without them)
Common Questions
Tankless Water Heater Repair & Flush FAQ
How often should I flush my tankless water heater?
In Orange County, annual flushing is recommended due to our hard water (15-25 gpg). If you have a water softener, you may be able to extend this to every 18-24 months. Neglecting annual flushes is the number one cause of premature tankless water heater failure.
What does an error code on my tankless water heater mean?
Error codes indicate specific problems — common ones include ignition failure, overheating, flame failure, and flow issues. Each brand uses different codes. Our technicians are trained on Rinnai, Noritz, and Navien diagnostic systems and can quickly identify and resolve the issue.
Why does my tankless water heater produce fluctuating temperatures?
Temperature fluctuations (the 'cold water sandwich' effect) can be caused by scale buildup, a failing flow sensor, or demand that falls below the unit's minimum activation flow rate. A flush and diagnostic check usually resolves the issue.
Can I flush my tankless water heater myself?
While it's technically possible with the right equipment (isolation valves, pump, and descaling solution), professional service ensures the flush is thorough and includes inspection of all components. Improper flushing can leave scale behind or damage the heat exchanger.
How long does a tankless flush and service take?
A complete tankless water heater flush and inspection takes approximately 1-1.5 hours. The descaling solution needs to circulate for 45-60 minutes to fully dissolve mineral buildup.
Tankless Water Heater Repair & Flush Throughout Orange County
We provide tankless water heater repair & flush services across all of Orange County. Click your city to learn about local plumbing needs:
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