I'm trying to install a new under sink filter and what should be a fairly simple installation is turning out to be a nightmare.
I've figured out most of the connections but what has me puzzled is something a plumber did a long time ago. It appears to be some sort of needle valve connected to the cold water pipe directly behind the cold water valve. The hose emerging from this goes into the old filter system.
I tried to close this valve but no amount of turns in either direction did anything, it just spins in place. Engaging the cold water valve does nothing either. How on earth to I stop water coming from this needle valve???