Pump comes on frequently

Pumps don't get waterlogged, but pressure tanks do. If the pump is cutting off/on frequently, as in just several seconds on and then several seconds off, and this is happening when water is being used, then you likely have a waterlogged tank. Now this is where it would get interesting. The Ruth Berry units, with which I am not familiar, are a pump/pressure tank integrated unit. The tank, which does not seem to be a bladder type, uses some sort of air control to regulate the amount of air in the tank. I'm not familiar with how they do that, though I think I could make a good guess at it. Still, I would suggest you call the company. The website is Ruth Berry Pumps | the worlds finest water pump (http://ruthberrypumps.com/). If I am guessing right, then the fix might not be too big of a deal.

On the other hand, if the pump is cycling when water is NOT being used, then you are likely looking at a leak. Could be anything from a checkvalve to a leaking toilet.