If your tankless water heater is throwing an error code, not producing hot water, cycling on and off, or has just stopped working, A&B Plumbing in Hickory, NC repairs it. We are a Navien Service Specialist - the only one in Catawba County - and we also service Rinnai, Rheem, Noritz, and other major tankless brands. Most repairs finish in one visit because we carry the common parts on the truck.
Call (980) 276-0199 Monday through Friday, 8 AM to 5 PM. If you know the error code on the display, mention it when you call - the dispatcher can sometimes triage on the phone.
Most common causes: gas supply issue (closed valve, low pressure, propane tank empty), ignition failure (cold igniter, fouled flame rod), flame loss during operation (gas pressure, vent restriction), or a flow sensor that does not detect water demand. The unit's error code points us to the cause - we test, then repair.
Inlet water filter clogged, flow sensor dirty or failing, gas pressure low under demand, or scale buildup choking the heat exchanger. A descaling fixes most scale-related symptoms; the rest are parts swaps after diagnosis.
Short-cycling on a tankless usually points to flow-rate problems - the unit cannot maintain a consistent demand. Aerators clogged with sediment, undersized cold-line supply, or a failing flow sensor are the typical causes.
Every modern tankless has a digital display that throws a numeric or alphanumeric code when something goes wrong. We read the code and the unit's recent error history (when available), then diagnose. On Navien units we can clear most codes after the fix without a factory tool.
The most common reason an older tankless starts failing in Catawba County. Hard water above 7 grains per gallon - common in outlying areas on private wells - drops minerals inside the heat exchanger over time. A proper descaling flush clears it; left untreated long enough, it eventually requires a heat-exchanger replacement.
A&B Plumbing is a Navien Service Specialist. Brandon is factory-trained on Navien's full residential lineup and we keep common Navien parts on the truck so most repairs finish in one visit.
Common Navien error codes and what they usually mean:
We can read the code, walk through the actual cause on site, and quote the repair before any parts change. Most common Navien parts (igniters, flame rods, flow sensors, fan assemblies, water-pressure sensors, inlet water filters) ride on the truck.
Hard water leaves minerals (mostly calcium and magnesium) inside the tankless heat exchanger over time. The buildup chokes flow, reduces efficiency, raises operating temperatures, and eventually throws error codes. A proper descaling pulls the buildup out and restores full performance.
What our descaling includes:
Annual descaling is standard for city water. For outlying Catawba County homes on hard well water without a softener, every 6 to 9 months is smarter. See tankless water heater service for the annual maintenance schedule.
Tankless units are designed to last 15 to 20 years with annual flushing - much longer than tank water heaters. That changes the repair calculus:
We diagnose, then tell you which makes sense. We do not push replacement when repair is the right call.
No hot water from a tankless unit is a same-day call during business hours. We dispatch from our Hickory and Conover offices and most service calls finish in one visit because we keep Navien and other common tankless parts on the truck.
If a tankless failure hits after hours, shut the water and gas off at the unit, document for insurance if there is any water damage, and call us at 8 AM. We prioritize overnight emergencies on the morning schedule. For the full after-hours protocol, see emergency plumber Hickory NC.
Same-day repair Mon-Fri 8 AM-5 PM. Navien Service Specialist. Common parts on the truck.
Call (980) 276-0199For routine tankless maintenance and pillar-level info, see tankless water heater service. For new tankless installs, see tankless water heater installation. For tank water heater repair, see water heater repair Hickory NC. Same-day emergency? Emergency plumber Hickory NC.
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