We bought our motorhome six years ago specifically so we could take our aging dogs with us and not have to board them or have them dog sat. Those dogs are no longer with us but we have three more to take their place. We try to take 3-4 month-long trips each year, just returning from a 9,000-mile cross-country journey that took us through 24 states and 18 national parks. Our dogs loved the trip.
When we go on excursions, we always limit our time out of the coach to five or six hours. Our dogs can hold it for considerably longer than that, but we won't make them unless there is an emergency. We leave the a/c on regardless of the outside temperature because even when it is cold outside, the coach can turn into an oven when sitting in the sun. I have two cameras set up; one to watch the dogs that covers the entire coach and one that shows the temperature on the thermostat. Unfortunately, these cameras only work when we have good wifi, which is less than half the time. Since we are visiting national parks on our vacations, we usually are not allowed to take the dogs with us, but when we are allowed, they go with us for exercise.
The only problem we have ever had with the dogs occurred this year when we were at the Grand Canyon. When we returned from our day's excursion, we had a ranger waiting for us at the coach because one of our Collies is a barker and watchdog supreme. The ranger informed us that the dog had been barking for most of the time we had been gone, about four hours. I apologized to the ranger for the problem but told him I thought I could show him why the dog was barking incessantly. The day before (we had been there for three nights already), a family moved into the site behind us that had three pre-teen girls who seemed to enjoy giving off shrill shrieks and screams while they were playing. They had bothered my dogs that night while they were outside but I said nothing about it, not wanting to create problems with my neighbors. It was that family who had called on the barking this day. I went inside the coach, put a leash on the Collie making the noise, and led him outside. As soon as he saw the girls, he bolted toward them, pulling me nearly off my feet because he knew they had been the ones screaming at the top of their voices that bothered him. He wanted to make sure they were all right because he recognizes someone screaming like that usually needs help. The girls began to shriek again when they saw the dog coming toward them. I stopped the dog, turned to the ranger and asked him, "Do you now see the problem?" He walked over to the parents of the children and told them they needed to keep their children quieter if they expected quiet from their neighbor's dogs. End of problem.
That issue has nothing to do with the OP's post but might exhibit other issues that can arise when traveling with pets. The laws regarding saving a pet when its life is in danger apply more to autos than RV's because when parked, your RV is your domicile, not your transportation. Then, laws pertaining to breaking into a residence will apply. To the OP, I suggest using your best judgment when determining when and for how long to be away from your babies. If there is a great chance that your a/c will not properly continue to function while you are away, do not leave them unattended. I have never had a situation like that except on one cross country trip when my a/c stopped working. Then, we didn't leave the dogs for any amount of time. Of course, without a/c, we cut our trip short and went straight home.