Hot air rework temperature to avoid solder melt on opposite end
I know this answer is a bit late ;>) but hopefully it will help others who search for something similar...

The goal when manually reworking circuit boards is to apply the right amount of heat. If there are lots of adjacent SMD passives, especially in smaller 01005 packages, then lower air flow is preferred otherwise you will have a mess on your hands. However, if you have to deal with a larger IC or a large ground plane, then more airflow will certainly help. Personally, I primarily use 360-380C with low airflow. 

If you leave the heat on too long, eventually the circuit board will get hot enough to melt solder way beyond the area you are reworking and that will cause all kinds of damage. If you are seeing components being affected on the opposite side of the board, then you are applying too much heat.