One can install an RV water heater following simple instructions. One should first remove air pressure from the tank. Once that is completed, one just needs to connect the colored tubes correctly.
No need to plug the block heater in if your not going to use the RV. If you plan on using the RV just plug in the block heater the day or two before you want to use the RV.
Gas water heater has an orifice for main burner and for pilot light, if not electronic ignition.
Yes
The water continues to run into and out of the water heater. There is just no flame to heat it up.
Have you turned the control from Pilot to On? Have you increased the temperature setting?
If the pilot light is on, the heater should come on by itself. If the pilot light is off then it has to be lit. If it will not stay on, the thermocouple is bad.
By reading the directions that come with each heater as each one is slightly different
There are many things that can go wrong with a RV but some of the problems that happen most often are burst water lines, leaky faucets, burst water heater, broken water pump, the toilet messes up, waste tank valves leak water, black water tank monitor lights always show full, hole punctured the RV rubber roof, broken or cracked window, and broken rooftop vents.
No, it is not dangerous. (Unless you are working with a water heater that is 20+ years old.) In any modern hot water heater, if the pilot light goes out a fail-safe will go off - preventing gas from leaking out. Also, there is a sensor so if there is not enough air-flow or oxygen with the water heater, it will shut off the gas.
If the tub is not getting hot water the issue is probably with the hot water heater. The hot water heater may have tripped a breaker or the pilot light went out.
Same as any hot water heater. Turn the gas valve to off.