Wet shennanigans

First off, I'm a total idiot. I bought a spa from a guy (Nick Huntley) in Ft. Wayne Indiana who assured me that everything was in good working order and there were no issues with it. I believed him and drove 2.5 hours to go pick it up. As soon as I rolled away with it he quit answering my texts and phone calls. When I got it home, I put it in it's place and hooked it up. When I started filling it with water it leaked like a sprinkler. All the manifolds were cracked and an elbow and one of the large jets were leaking. It was only about half way filled when I discovered the leaks. At that point I thought I would see if the pumps were working and I turned on all three pumps. There was nothing. The board would click but the pumps did not come on. I hadn't primed the lines and I'm sure the pumps were dry at that time. Is there some sensor that knows the pipes are full of air and prevents the pumps from coming on when dry? I figure it's either something like that or the pumps are seized also.