Surgery - Colorectal. In brief: Yes, most docs can. Most hemorrhoids should first be treated by conservative measures, such as bulking the stools, education to avoid bad habits like straining, sitting for long periods of time, etc.
Either system will have a burner. 23 years may very well be beyond the typical life expectancy of a oil burner, but a furnace or boiler should last considerably longer than 23 years. The boiler of my house here in MA is 58 years old and still works fine. I am starting to consider replacements, however.
your first batch of coals will probably keep the oven hot for 30 to 45 minutes that s long enough to cook most things but you sure don t want to let the oven go out for those 1 hour or longer meals just make sure you check your oven every 20 or 30 minutes to see that the coals are ok