Tankless Water Heater Repair in Texas
Tankless units are more complex than tank water heaters, and Texas hard water makes maintenance non negotiable. We repair, install, and descale every major tankless brand sold in Texas.
Why Tankless Units Fail Faster in Texas
Tankless units heat water on demand by passing it through a small heat exchanger. In Texas hard water, mineral scale builds up on that exchanger faster than in a traditional tank, since all the water passes through the same compact, high heat surface. Without regular descaling, restricted flow and reduced efficiency follow, and the manufacturer can void your warranty.
Common Tankless Problems We Fix
- Error codes: Rinnai Code 11 or 12, Navien E003, Noritz fault codes. These usually trace back to ignition failure, gas supply issues, or heat exchanger scaling.
- Reduced hot water flow: Almost always sediment scaling in the heat exchanger from hard water.
- Cold water sandwich: A brief burst of cold water between hot water draws, often a flow sensor or venting issue.
- No hot water at all: Ignition failure, gas supply problems, or a failed control board.
- Short cycling: The unit turns on and off rapidly, often linked to low flow rate or scale restriction.
Tankless Descaling
Descaling flushes mineral buildup from the internal heat exchanger using a pump and descaling solution circulated through the unit. In Texas hard water, we recommend descaling every 6 to 12 months depending on your local water hardness. Extreme hardness cities like Round Rock, Kyle, and San Marcos need the more frequent end of that range. Descaling runs $150 to $300 and takes about an hour.
Brands We Service
- Rinnai, including the Sensei RU199iN
- Navien, NPE and NCB series
- Noritz, EZ and NR series
- Rheem tankless
- AO Smith tankless
| Problem | Most Likely Cause | Typical Cost to Fix |
|---|---|---|
| Error code displayed | Ignition fault, flow sensor, or overheat protection | Diagnosed on site, $150 to $400 |
| Reduced flow rate | Scale restricting the heat exchanger (San Antonio especially) | Descale service, $200 to $350 |
| Won’t ignite | Gas supply, ignition, or venting fault | $200 to $500 |
| Cold water sandwich | Normal reheat delay, not usually a fault | No charge if within normal range |
| Inconsistent temperature | Undersized unit or scale buildup | Varies, assessed on site |
Helpful Articles
Frequently Asked Questions
How much does tankless water heater repair cost?
Most repairs run $150 to $500 depending on the part. Descaling runs $150 to $300.
How often should I descale my tankless unit in Texas?
Every 6 to 12 months depending on local water hardness. Extreme hardness cities like Round Rock and Kyle need descaling every 6 months.
What does a tankless error code mean?
Codes vary by brand and cause, from ignition failure to gas supply issues to heat exchanger scaling. Persistent codes need professional diagnosis.
Is my tankless warranty voided if I skip descaling?
Often yes. Most manufacturers require documented regular maintenance in hard water areas to keep the warranty valid.
Tankless Acting Up? We Can Help Today
Licensed through TSBPE. Insured. Same day service across Texas. Email info@waterheaterservises.com anytime.