In winter, if I'm in a campground that's new to me, I put the water pressure regulator on and check the pressure then remove it and go with the heated hose. If I had to use the regulator I'd fill my on board tank the drain it and the hoses and use my on board tank until it warmed up.
Dick, Joyce, Diego, Picatso and Gustav
2017 3720 RL, MorRyde pin box
2017 3500 Dodge Maxi DRW 4X4, Pullrite Hitch, IS, Disk Brakes, 3rd AC, Winegard Traveler, Bathroom door mod, Dometic 320, couch for desk swap, etc.