1. When the water is running there is water leaking from behind the handle

This is a common maintenance occurrence for any packed valve of any brand or manufacture.  It is overcome by simply tightening the packing nut with a crescent wrench.  This will force the packing tighter around the stem to eliminate leakage. 

This valve has 2 packing nuts the need to be tightened. Below is where they are located:

Occasionally, the packing will need to be replaced if the packing nut has been repeatedly tightened. 

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