1990 T1700 Solaris Water Leak

[sallyforth]

Hello all, I'm so grateful for this group, you've all helped me out so much in the past. Here's hoping we can solve one more mystery as I've sold my old gal and as we hooked up the city water there is now water pouring out from below. I've been on a video Chat with the new owner and the water did work in the summer, she was winterized. I will be going out in the AM to see it in person. The hot water heater is an Atwood and it is only 4 yrs old. Sadly, I know there are no diagrams for plumbing, we've worked out that the leak is between the pump and HWH. They said when they turned on the water some came out and then it started to leak and they turned it off. When they removed paneling for some reason the holding tank was half full and when the pump was turned on with no city water, it leaked. Any thoughts, diagrams, solutions would be greatly appreciated. Thanks so much as always!