Re: First time RV'r - a few questions
I would make sure that the CO detector is in working order, even though they were only added in more recent years. They are rather like seat belts in that you seldom need one, but if the worst happens it is much better if it is there and working.
An RV furnace uses all outside combustion air and there is no possible entry of CO into the RV unless the furnace has a very major problem, and that is extremely unlikely with an RV that is only five years old and lightly used. The refrigerator also does operate on propane when not connected to 120V shore power, but it is even less likely to be a source of CO. In addition the water heater also uses propane but never have I heard of one of those sending and CO into an RV. The highest probability source would be an on-board generator set, if the unit has one. Internal combustion engines are the #1 source of such gas and sitting still is when it would be likely to happen, if you use the generator while camped. Even then, it isn't a common problem but I would never be without a working CO detector and I always wear my seal belt.
I suggest that you make sure that you know how to connect the city water supply and to fill the water tank. Lean how to turn on the water heater and the furnace as well as how to use the air conditioner. The air conditioner on the roof will only operate when parked and connected to 120V power, unless there is a built in generator set, which could supply power if available. Ask how to connect the sewer hose and to dump both of the waste water tanks as well. Those are jobs with a real potential to give you a baptism by something more repulsive than fire if you do not know how to use them. It is no big deal if you know, but caution is the key.
The refrigerator, water heater and furnace all require 12V electric power to operate, even when there is 120V power from the shore power cord. All RV appliances require 12V-DC power and assuming everything works the power is supplied by a 120V/12V converter when connected to shore power and from an on-board battery (not the one to start the chassis engine) when parked or with the engine not running.
I suggest that you also discuss how you level the RV for use, as it can be pretty uncomfortable to live in an RV that is far out of level and if bad enough the refrigerator could stop working. If you have never driven an RV, use care and always watch the mirrors to know what is happening along the sides as well as behind you. When you turn, a vehicle that is 30' of so long will tend to cut across the corners, and the extended rear behind the axle will tend to swing in a wider arc than does the wheels so beginners often find that they hit things on the inside of turns and outside the range of travel with the rear of the RV.
I suggest that you have a pair of FRS radios to use between yourself and some trusted guide for backing the RV into RV spots as not all parks will have sites that you can just drive through. I would also suggest that you never back the RV without a ground guide (with radio) out behind you to watch for traffic and to stop you if you get too close to a tree, water hydrant, or power pedestal. Develop a habit of walking completely around the RV after you are ready to travel, but before you turn a wheel and look up, down and under everything. It is very common for inexperienced RVers to drive away with a hose or power cord still connected or the TV antenna up. And extra few moments in checking things will save grief later. Most of us make that a habit even with years of RV experience.