I have measured the voltage across the coils when the burner short cycles and changes from 120 to 0 volts. If it were the coils, then the voltage would remain across the coil when the flame cuts off ?? I also noticed that voltage across the thermistor is very noisy and variable. Is this typical or should the signal be relatively clean from noise (i.e. voltage variation from 0.9 to 1.5 volts quite rapidly. When wires removed and just measure resistance, the thermistor measures a very steady resistance that would be expected for the room temperature.