I told my acquaintance what I thought it was, but he dismissed my idea
My friend called me a few days ago, looking for some advice. He was having some issues with his heating unit. He told me that even though his gas furnace was running it wasn’t heating his home, but I knew that my friend’s house was incredibly old, but I also knew that the furnace wasn’t, so I was able to mentally cross out that idea. I was planning on seeing my acquaintance in a couple of days anyway and then I could take a look myself. When I went over and visited my acquaintance I looked over the heating unit myself and it looked fine. I also looked at the thermostat which also looked fine. I began to speculate that it actually wasn’t an issue with the gas furnace, but most likely with the HVAC duct. My acquaintance had lived in this house for close to 20 years and I did remember reading that the HVAC duct needed to be replaced eventually. I told my acquaintance what I thought it was, but he dismissed my idea. He seemed hyper focused on the HVAC unit and thought that it had to be an issue with the actual heater. He called a professional heating and air conditioning worker out and the air conditioner worker took his time examining his house and the heating and air conditioning unit, but the air conditioner worker reached the same conclusion that I did, it was truly the HVAC duct having several holes in it and needing to be replaced, not the actual central furnace itself. My acquaintance didn’t want to confess that I was right, but silently paid to get the HVAC duct replaced.