A flame detection system is designed to detect leakage in flame sense circuits. The flame detection system includes a flame sensor, an amplifier, a detection circuit, and a microcontroller. Flame sense circuitry use operational amplifiers that needs negative voltage supply for its operation. Negative supply voltage properly measures negative input signals. Once a leakage current in the flame detection system is determined a shutdown signal is provided to shut down a flame sensor when the leakage current condition is determined.