Oren wrote:
On Sat, 29 Mar 2014 07:35:01 -0700, "Pico Rico"
wrote:

you know, the valves under the sink. They are both stuck (open,
fortunately). Is this a common problem? What is the solution? How do you
prevent this from happening?


One way to _help_ prevent them from sticking is to keep them
partially closed after install - say 1/8 of a turn. This allows them
to be opened a tad before being closed the next time. IOW, never keep
them fully opened.

Hi,
Ditto, I never open it fully. On any valve for that matter.
I'd try to turn it with good leverage using a vise grip
pliers. Worst rreplace it with a ball valve.