Firefly TruTank error code Light blue line under tank reading
The value shown is NOT a valid reading. Firefly: shown when a sensor cannot work correctly - e.g. the tank is overfilled with no air gap at the top, or the tank module lost power / its constant-power wire was disconnected while the tank was overfilled. The line clears by itself once the sensor is back within working parameters.
What to check, and in what order, is in the app. The flow Firefly TruTank - tank not reading, invalid (blue line) or wrong level walks this code step by step with the pass/fail measurements, wiring schematics and procedures that go with it, and it works offline in the bay.
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- TruTank Troubleshooting Guide revision 6Firefly Integrations
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