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Industrial Error Code Fixes

Tankless Water Heater Error Codes and Repair Guides

Tankless water-heater error-code guides for flow, ignition, overheat, venting, descaling, and sensor faults.

Common tankless water heater fault patterns

  • Ignition, flame loss, flow sensor, thermistor, overheat, and freeze-protection errors.
  • Venting, condensate, scale buildup, combustion air, and gas-supply problems.
  • Control-board, fan motor, pump, and recirculation faults on tankless systems.

Tankless repair decision checks

  • Confirm gas, water flow, venting, and descaling history before buying sensors.
  • Use exact brand and model context for igniters, flame rods, flow sensors, and pumps.
  • Treat gas, venting, combustion, or repeated lockout faults as technician work.