I have been trying to find an air leak in the fresh water
system. Some where there is a leak allowing the water
to flow back to tank which means we have to run the water for a while to get the air out of the line and pick up the water again. There is no water leak at any of the filters, hose clamps, etc. that I can find. I have installed a back flow valve ahead of the filters, and selector valve. I have replaced washers in filters, tightened clamps, and cussed at it!!! The only place I think it can be is in the ball valve itself. Is it possible for the valve to leak air but not water?