Take a look at the picture below. The leaking/dripping part is the thing that juts out from the main pipe.
So help me out ....... what is this? Some kind of pressure release or something? Appears to be a brass fitting.
Is this an easy replace? Screw off old, screw on new?
Another issue -- I don't have a shutoff valve prior to this piece. The main shutoff for the house is located downstream - it's up past the top of the photo after the water gets past the pressure tank.
Also downstream from this point there is a drain valve that I can connect to a hose. Do I basically have to kill the electricity and drain the whole system in order to work at this area?
To help orient you - the water enters the house from the pipe in the lower left of the photo. Then it comes to this junction point - to the left is the pressure tank, to the right is mystery part. Continuing up past the top of the screen is the rest of the house plumbing.
Appreciate all your help.