How to remove old multi turn water inlet valve
that is a compression fitting,the nut is against the wall plate.using 2 pairs of adjustable wrenches,use 1 wrench to hold the valve(holding the valve just under the outlet hose)use the other wrench to loosen the nut.when done the valve will pop off leaving the nut and a brass ferrule.carefully remove the ferrule with pliers(wary not to crush the pipe,grip the ferrule and twist back and forth while putting pressure in a forward,pipe opening,direction)remove the nut,then replace with new valve as above,in reverse