Coronado water heaters take more wear than most people realize. Salt air is hard on anything metal, and the closets and garages they sit in are tight. Sooner or later yours will need attention, and calling early lets you deal with it on your own schedule.
The early signs to watch for are water that's cooler than it used to be, hot water running short, a pilot that keeps going out, or rust or moisture at the base. Any one of those is a good reason to call, while there's still time to weigh a repair against the tank's age, size a replacement to the household and check what the install spot needs.
If a repair is the right call, that's what you'll hear. If the tank is near the end of its life, you'll hear that too, with time to plan the replacement. Either way it's laid out in plain English, and the decision is yours.