The job of an HVAC technician would be so much easier if furnaces could talk, not because it would give us someone to chat with while we work on repairs, but because a talking furnace could simply tell homeowners when something was wrong. It could announce it had unbalanced ducts, a clogged filter, or a misaligned blower wheel. Then, a homeowner could call a tech, and we’d get to work fixing it. Unfortunately, a furnace can’t just tap somebody on the shoulder and say it’s not feeling well. It can, however, make weird noises when problems come up—noises that often provide valuable clues as to what’s going on. See, the blower wheel, the ducts, and even the burner produce odd or loud sounds when they need to be repaired, sounds homeowners are likely to notice. While, let’s face it, furnaces are never going to be able to articulate exactly what’s happening inside of them, they’ll still find audible ways to let us know when they need our attention.