What corrective action should be taken when the FF terminals are jumped after startup and the control goes into lock-out?

When the FF terminals are jumped after startup, and the control enters a lock-out condition, it indicates that there is a safety mechanism triggered due to a fault detected in the system. The correct action in this scenario involves replacing the control. This is essential because the lock-out condition typically indicates a significant issue that the control unit has detected, often related either to safety or system malfunction, which it cannot resolve autonomously.

If the control unit continues to remain in lock-out mode, simply resetting the system would not address the underlying problem potentially leading to repeated failures or safety hazards. Therefore, assessing and replacing the control unit ensures that the system is able to operate effectively without recurrent lock-outs. This action also helps maintain the integrity of the heating system, ensuring safety standards are upheld for ongoing operations.

In this context, checking the power supply or changing the thermocouple may also be appropriate troubleshooting steps under different circumstances, but in this specific case, replacing the control is the most direct and effective corrective action to take.