The original versions of the 2V-700 system didn’t prevent pushing air back into the cooling system. The technician had to monitor the refill process. The current tool configuration has an automatic shut off valve that prevents air from entering the system. However, the tool will continue to push coolant into the system until the tool is empty. There may be more coolant in the tool than the cooling system can hold. Check the coolant level in the tool prior to use.