Tankless Water Heater Repair in Portland, OR
Tankless unit flashing an error code or not heating? Our Portland plumbers diagnose and repair gas and electric tankless heaters the same day — ignition, flow, scale and venting faults — at an upfront price.
- Same-day diagnosis & repair
- All brands & error codes
- Descaling & flushing
- Discuss the repair scope before work
Before arranging repairs
Do not repeatedly reset a unit that reports a combustion, gas or ventilation problem. Follow the manufacturer’s safety instructions and seek professional assessment.
Same-day water heater service — repair or full replacement
- Same-day repair or replacement available
- Upfront price before we start — no surprises
- Discuss the repair scope before work
- Stocked for most brands — first-visit fix
A tankless (on-demand) water heater only makes hot water when it can ignite, breathe, and sense enough water flow. When any of that is off, you get no hot water, lukewarm water, or an error code on the display. Most faults are repairable the same day — and unlike a tank heater, a tankless unit is built to be serviced part-by-part rather than replaced.
Common tankless problems we repair
Gas and electric units — we diagnose the root cause, not just reset the code.
No hot water
Closed valve, clogged inlet filter, failing flow sensor, gas-supply issue, or scale in the heat exchanger.
Ignition / flame failure
Dirty igniter or flame rod, gas pressure, or a blocked burner keeping the unit from firing.
Insufficient flow
Demand beyond the unit's GPM, scale buildup, or a restricted inlet filter limiting hot water.
Scale / mineral buildup
Mineral scale in the heat exchanger triggers maintenance codes and weak heating — cleared by descaling.
Venting / airflow faults
Blocked intake or exhaust venting causing combustion errors and safety shutdowns.
Cold-water sandwich
Frequent hot-cold-hot swings from a failing flow sensor or an undersized unit.
Rinnai error codes
- 10 — combustion / blocked air or exhaust vent
- 11 — ignition fault (igniter, burner, gas valve)
- 12 — flame failure (won't stay lit)
- 14 — thermal fuse / overheating safety
- 16 — over-temperature warning
- LC — scale buildup / descaling due
Navien error codes
- E012 — flame loss
- E016 — heat exchanger overheated
- E030 — exhaust overheat
- E060 — venturi / combustion abnormality
- E002 — low water pressure
- E760 — flushing / descaling alarm
Seeing a different code (Noritz, Takagi, Bosch, Rheem)? Read it to us on the phone and we'll tell you what it means and bring the right parts.
Descaling & flushing
Over time, dissolved minerals collect inside the heat exchanger and choke a tankless unit's performance — triggering scale codes (Rinnai LC, Navien E760), weak heat, and premature wear. A professional descaling flush circulates a cleaning solution through the unit for about 45–60 minutes to clear it out.
We recommend a flush at least once a year. Staying on top of it is the single best way to extend a tankless heater's life and avoid sudden no-hot-water calls.
Repair or replace?
Tankless units last 15–20 years and are designed to be repaired part-by-part. Repair almost always wins unless:
- The unit is near end of life (15–20 yrs)
- The repair would exceed ~50% of a new install
- It's needed multiple repairs in one year
Time for a new one? See tankless installation or replacement.
Tankless brands & cost
We repair gas and electric tankless units from Rinnai, Navien, Noritz, Takagi, Bosch and Rheem, among others, and carry common flow sensors, igniters, flame rods and control boards.
| Professional descaling flush | $150 – $300 |
| Common part repair (sensor, igniter, valve) | $150 – $600 |
| Major repair (heat exchanger, control board) | $600 – $1,300 |
Estimates for guidance; you get an upfront flat-rate quote before any work, with no after-hours surcharge.
Error code or no hot water? Fixed today.
We read every brand's codes, carry common tankless parts, and descale on site — same-day across Portland, with no overtime fees.
Local help for Tankless Water Heater Repair
From the first call to a clean finish, our Portland plumbers handle tankless water heater repair with upfront, flat-rate pricing and no overtime fees — day, night, weekends and holidays.
Call (971) 367-8197Tankless repair questions
Read us your error code and we'll tell you what's wrong.
Why is my tankless water heater not getting hot?
Tankless units need gas, airflow, and adequate water flow to fire. No or low hot water is usually a closed valve, clogged inlet filter, failing flow sensor, scale in the heat exchanger, or an ignition fault. We diagnose it the same day.
What do tankless error codes mean?
On Rinnai, 10/11/12 point to combustion, ignition and flame problems; 14/16 are overheating; LC means scale. On Navien, E012 is flame loss, E016/E030 are overheating, and E760 means a descaling flush is due. We read the code and fix the underlying fault.
How often should a tankless water heater be flushed in Portland?
At least once a year, and more often if you see scale codes. A professional descaling flush takes about 45–60 minutes and clears mineral buildup from the heat exchanger to restore performance.
Can a tankless water heater be repaired, or do I need a new one?
Most issues — flow sensor, igniter, flame rod, control board, scale — are repairable. Replacement makes sense only if the unit is near its 15–20 year lifespan or the repair exceeds ~50% of a new install. See tankless installation.
How much does tankless water heater repair cost in Portland?
The price depends on diagnosis, access, parts and the agreed work. Ask what is included in the assessment and request the repair scope and price before authorizing work. Additional restoration or specialist work should be identified separately.
Why does my tankless run hot then cold (cold-water sandwich)?
A short cold burst between hot draws is often normal, but frequent swings can signal a failing flow sensor or a unit that's undersized for your demand. We can test and advise.
Why won't my tankless water heater ignite?
No ignition usually means a gas-supply problem, failing igniter, dirty flame sensor, blocked burner, or a blocked vent (Rinnai 10/11, Navien E003). We pinpoint and repair it the same day.
Which tankless brands do you repair?
Gas and electric tankless units from Rinnai, Navien, Noritz, Takagi, Bosch and Rheem, among others. We carry common parts and can often repair the same day.
Other Plumbing Services in Portland
One call covers every plumbing need, anywhere in the metro.
Water Heater Repair
No hot water or a leaking tank? Same-day gas, electric & tankless repair.
Water Heater Replacement
Old or failed unit swapped same day, hauled away and code-compliant.
Water Heater Installation
New tank or tankless installs sized right for your home.
Drain Cleaning
Clogged or slow drains cleared fast — no harsh chemicals.
Hydro Jetting
High-pressure cleaning that blasts grease, roots and scale.
Sewer Line Repair
Camera diagnosis and trenchless repair of damaged laterals.
Sewer Line Cleaning
Roots and blockages cleared from your main sewer line.
Sewer Line Replacement
Trenchless pipe bursting or a targeted dig that lasts decades.
Sewer Camera Inspection
HD camera locates the exact problem underground.
Burst Pipe Repair
We stop the flood and repair burst pipes the same visit.
Leak Detection
Non-invasive location of hidden water leaks before they spread.
Slab Leak Repair
Pinpoint and repair leaks under your concrete slab.
Pipe Repair & Repiping
Repair or repipe for copper, PEX and old galvanized lines.
Gas Line Repair
Safe repair and leak-testing of natural-gas and propane lines.
Water Line Repair
Repair leaking or broken main water-service lines.
Frozen Pipe Repair
Thaw and repair frozen, split pipes before they flood.
Faucet Repair
Drips, low water pressure and worn cartridges fixed fast.
Toilet Repair
Clogged, running, leaking and overflowing toilets repaired.
Garbage Disposal Repair
Jammed, humming or leaking disposals repaired or replaced.
Backflow Testing
Backflow testing requirements, scheduling and reports.
Commercial Plumbing
Same-day plumbing for restaurants, offices and retail.
How the repair scope is decided
The technician checks the symptom against the manufacturer’s diagnostics and the unit’s installation. Water flow, service history and any error code help separate a maintenance issue from a failed component.
Work may involve maintenance, an approved component replacement or correction of a related installation issue. Cleaning or descaling is only part of the solution when the findings support it; it is not a universal repair for every error.
Ask which diagnostic steps were completed, which component or condition is at fault and whether parts are available for the model. Installation and manufacturer requirements determine the appropriate repair.
What to have ready before a visit
Have the model, error code and recent service history ready. Explain whether hot water is absent everywhere, intermittent or limited to a particular fixture, and whether the problem occurs at low flow.
Portland’s Bull Run supply is soft; groundwater has a different mineral profile. Maintenance should follow the equipment instructions and actual water conditions, rather than assume every Portland property has hard water. Portland Water Bureau water-quality report.