A tankless water heater that won't ignite, cycles hot and cold, or has never been serviced since installation is usually dealing with one of two things: a sensor or ignition fault, or mineral scale building up inside the heat exchanger from years without a descaling flush. We diagnose which one it is with the actual unit's fault codes and service history rather than guessing.
Trained on Rinnai, Navien, Rheem, and other major tankless brands.
Most tankless units display an error code, we read it instead of guessing.
Flushing service that extends the unit's life and restores flow.
A flat quote before any work begins.
Middle Tennessee's moderately hard water is a bigger factor for tankless units than it is for standard tanks, since a tankless heat exchanger has much tighter internal passages that scale narrows faster. A unit that's never been flushed, often because a homeowner installed it and assumed it was maintenance-free, is the single most common reason we see reduced flow and inconsistent temperature on tankless service calls.
Common SignsOften a sensor, ignition, or venting fault reading a real error code.
Can indicate scale buildup restricting flow through the heat exchanger.
A classic sign the unit is overdue for a descaling flush.
Most manufacturers recommend annual flushing that a lot of installs skip entirely.
We'll read the fault code and give you a straight answer.
Most tankless units display a specific error, which narrows the cause immediately.
Sensor and ignition check, or a full vinegar/descaling solution flush.
Faulty components replaced with compatible parts for your brand.
Confirm consistent temperature and flow before we leave.
We see a specific pattern in Franklin's newer construction: tankless units installed during the original build that have never had a single descaling flush years later. It's not a failure on the homeowner's part, tankless units simply don't announce their maintenance needs the way a tank's sediment rumble does. A once-a-year flush is a small, inexpensive habit that keeps one of the more expensive plumbing fixtures in the house running at its rated lifespan instead of failing early.
FAQsMost manufacturers recommend annual flushing in a moderately hard water market like Franklin's, though usage and water conditions can shift that slightly.
Tankless units are rated for 15-20+ years, considerably longer than a tank. Most repairs on a unit under that age are worth doing rather than replacing.
Rinnai, Navien, and Rheem are the most common in Franklin, and we service all three along with most other major tankless brands.
It's possible for a comfortable DIYer with the right isolation valves already installed, though a professional flush also includes a fault-code and component check most self-service misses.
We'll read the fault code and give you a straight answer.
☎ Call (615) 616-0512From Downtown Franklin and Cool Springs out to Brentwood and Spring Hill, our technicians cover the full city and its surrounding Williamson County neighborhoods.