When we are in very cold conditions, I place a small electric heater on the floor of the pass through aimed to the space between the door and the left partition of the wet BAY, and have never had anything there freeze. If the valves are damaged, this is what those valves are that they used.
https://www.trekwood.com/products/12...Drain-SPP44A-G
If you do replace the valves, this is the tool I have used with excellent results,
https://www.amazon.com/IWISS-Fasteni...zcF9tdGY&psc=1
Lowes has the crimp clamps or you can also get them on Amazon. All the PEX in these rigs is 1/2".