You're smart to be cautious—HVAC wiring isn't something to mess around with lightly. I've tackled a few thermostat issues myself, and even when things seem straightforward, there's always that one wire or connection that can trip you up. Good call on keeping an eye on it, though. If it's stable now, you're probably fine, but HVAC gremlins have a knack for popping back up when you least expect them...usually during a cold snap.
Yeah, HVAC wiring can definitely throw curveballs. I had a thermostat issue last winter—thought I'd nailed it after watching a few YouTube vids, but sure enough, two weeks later it started acting up again right when temps dropped. Ended up calling someone in, and honestly, the peace of mind was worth the cost. Sounds like you're on top of it though, fingers crossed yours stays stable!
