This morning I pulled the shower button and nothing came out of the shower head. Water just came out of the facet. The unit is a "WALTEC" and we installed it in 1993. I had noticed for a while now some water coming out of the facet during a shower but this time all the water came out of the facet. Will I have to access the wall behind the shower to install a new unit or only a part required?

Hey Stretch,

Waltec has been bought by Delta and I can't pull up any specs off the net.
However, diverter problems don't require that you replace the entire valve.
They are mostly caused by mineral buildup or crud caught up in the seats.
Try this. Pop off the nameplate on the knob and remove it. Now remove the screws securing the escutcheon,(face plate). Unscrew the packing nut that secures the diverter and pull out the diverter assembly. Clean the diverter assembly and then check the seats in the valve body and remove and trash or crud that's built up in there. Lube any moving parts and reassemble. Work better now? More questions? I'm as close as a click. Tom

Thanks that worked. It only required a little rubber seal. I cleaned the unit as you suggested. Working great! :)