After repairing a leak, what verification step should be performed before resuming recharge?

• A. Re-check the detectors only
• B. Purge the system completely
• C. Re-check the system and perform purging if necessary, then resume only when detectors show safe readings
• D. Increase recharge pressure briefly to test

Answer: (C)

After repairing a leak, the priority is to ensure there is no flammable vapor in the system or surrounding area before adding more refrigerant. Rechecking the system confirms that the repair held and there are no lingering leaks, and rechecking the detectors verifies the area safety. If the detectors indicate any flammable vapor, purge the system to remove that gas or air from the lines and compartments. Only when the detectors show safe readings should you resume the recharge. This approach prevents reintroducing refrigerant into an environment that could ignite and avoids leaving the system obstructed by contaminants or pockets of gas. Increasing recharge pressure or purging unless necessary are not appropriate steps, and relying on detector checks alone risks missing leaks or trapped gas.