Repair and descaling for tankless water heaters: error codes, ignition faults, mineral buildup, flow sensors and cold water sandwiches.
Tankless water heaters promise endless hot water, and when they work they deliver. When they do not, the symptoms can be baffling: cold bursts in the middle of a shower, an error code that will not clear, a unit that shuts off when you open a small tap, or hot water that takes a long time to arrive. In Nashville, where hard water leaves scale on heat exchangers, regular service is the key to long life, and many failures come from neglected maintenance.
We read error codes, check ignition and flame, flow and temperature sensors, the heat exchanger, fan, condensate drain and venting, and we flush the unit with a descaling solution when needed. We also check the gas supply and sizing, because an undersized line can starve a tankless unit. You get a plain explanation of what we found and a maintenance plan that fits your water.
We decode the fault, test the part and fix the cause so the code does not return.
Hard water scales the heat exchanger. A descaling flush restores flow and efficiency.
Dirty sensors, weak flow and venting issues keep the burner from firing and are corrected.
Yearly flushing and filter cleaning extend the life of the unit.
Drag the handle to compare.
BeforeAfterFaults decoded and fixed.
Restore flow and efficiency.
Reliable firing.
Safe operation.
Fit for your water.
Hot water verified.
Every topic has its own page with what to expect and how we approach it.
Topic guideWater Heater Types ComparedGas tank, electric tank, tankless and heat pump water heaters compared on cost, space, hot water supply and…Learn more 
Top appliance brandRinnaiA Japanese maker known for gas tankless water heaters that supply hot water on demand to homes and…Learn more Top appliance brandNavienA Korean maker of high-efficiency tankless water heaters and combination boilers for homes and light commercial use.Learn more Pick an appliance and tick what you see and hear to get likely causes, safety notes and the service page that fits.
You tell us the brand, the model and what the appliance is doing, and we give you early guidance and set a visit that fits your day.
A technician inspects the appliance, reads codes and tests parts with meters and gauges to find the real cause.
You get a plain written plan with the parts, the work and the cost, and honest advice on repair or replace.
We repair with parts matched to your model, or install the new appliance level, connected and secured.
We run the appliance through a full cycle, check for leaks and show you how it works before we leave.
We keep a record, answer questions and stay available if anything seems off after the visit.
Low flow, scale, a sensor fault or short cycling can cause cold water sandwiches.
It points to a specific fault such as ignition, venting, flow or a sensor. We test and correct it.
Usually once a year, and more often with hard water.
Often yes, because it burns more gas at once. We check the supply.
We service most major brands. Call with your model number.
Gas Water Heater RepairCareful repair for gas tank water heaters: pilot and ignition problems, thermocouples, gas valves, anode rods and leaks.Explore 
Electric Water Heater RepairRepair for electric tank water heaters: heating elements, thermostats, breakers, relief valves, leaks and lukewarm water.Explore 
Hot Water Heater InstallationWater heater replacement: tank and tankless, gas and electric, with proper venting, pan and drain, relief valve and…Explore 
Appliance Maintenance PlansSeasonal maintenance visits for refrigerators, laundry, dishwashers, ranges and water heaters to catch problems early.Explore Tell us about your appliance and we will call you back to set up a visit.
Or call (615) 357-7797 to talk now.
