Wait, you can freeze up a whole system with just a little air left in the lines? That's wild. Makes pulling a proper vacuum seem way more important than some guys treat it. No wonder call-backs happen.
Hey @stone.claire, I see your point about fixing things by doing them right at first. But sometimes, even when you do everything perfect, problems can come up later. For example, a roof put on right might still leak if there's a really bad storm. So it's not just about the first try, but also what happens after.
Yeah, forgetting to purge lines on mini-splits is a classic mistake. Honestly, even a little air left in the system can cause low cooling or freezing up. Tbh, I always pull a deep vacuum for at least 30 minutes and use a gauge to check. Ngl, I've been there wasting hours on call-backs because the vacuum wasn't right. Now I make sure the lines are clear before I even start the unit. It just saves so much trouble later.