My friend Charles is a master electrician, but he somehow doesn’t really know anything about heating and air conditioning. Every time that we need something rewired or a new fuse put in or a new light fixture installed, Charles is the first one to come over and help us do it. He’s a really great electrician and he knows exactly what he’s doing. It’s funny, though, whenever Charles has a problem with his air conditioning system or with his electric furnace, he always calls a professional HVAC technician to come over and help him. I would think that Charles would have a pretty good idea about how to fix a heater or an air conditioner, since he’s a master electrician. But when I asked Charles about that, he said that HVAC systems are completely a different animal than regular electrical work. He said that he doesn’t ever mess with his furnace, his thermostat, or with his air conditioning system. Charles will be the first guy to work on a messed up fuse box or on some faulty wiring, but he will not do anything to try and fix a thermostat or a furnace or an air conditioner. I think that’s kind of weird, but it is what it is. I guess just because you know how to do electrical work doesn’t mean you know how to do HVAC work, too. If I ever learn to work on HVAC systems, I will definitely go over to see Charles when he has issues with his heating or his air conditioning, He certainly has helped me enough times and I’d love to return the favor!