Had an hvac guy inspect our furnace today. It's become clear over the past couple of weeks, with temperatures down in the 30's, that we will need the furnace more than we thought. He glanced at the furnace and said "Wow! That's pretty old." After doing various tests on it he pronounced it in fine working function but he thinks we'll want to replace it relatively soon because it will just start breaking. and breaking and breaking and breaking... I also asked him to look over our duct work. It's a mess. Half of it is up in our attic for no logical reason and hidden behind drywall. From what he could see it's obviously leaky. He also had good thoughts on whether we would want to do central a/c (it's ready but he recommended doing a pressure test of the line. Since the never used a/c line is 43 years old if it won't hold pressure we would need to start from scratch, which would include ripping out drywall so that we could install a new one.)