I’m working on installing Mitsubishi mini splits in my house, and I have a couple of questions that I’m hoping someone can help with. I know that Mitsubishi recommends a mounting height of 5.9 to 7.5′ from the floor to the bottom of the bracket. I’m assuming this is based on an 8 or 9′ ceiling, and I was wondering if this should change at all when dealing with a sloped ceiling. In my case, the ceiling goes from 11′ to 8′, but it’s about 10′ in the area where the head will be. I will probably go with the max recommended height of 7.5′ from the floor to the bottom of the bracket, because it seems to look better a bit higher. I just want to make sure this height will be okay and if I need to make any changes based on the ceiling.

My other question involves the insulation for the linesets. I was originally going to make my own, but I ended up buying preinsulated ones. I do plan to redo the flairs. They have 1/2″ insulation, and in the manual, I noticed that Mitsubishi recommends an insulation thickness of 5/16″. It says that “Excessive insulation may cause incorrect installation of the indoor unit, and too little insulation may cause condensate to form.” It seems like almost all of the premade linesets are 1/2″. Does anyone know how critical this is, and where I could get 5/16″? I noticed that even the Mitsubishi branded Diamondback linesets have 1/2″ insulation. I usually shop at SupplyHouse or Amazon, and the next size down looks to be 3/8″. Would this be a better alternative?

I appreciate any advice! I tend to overanalyze everything, and I make myself even more confused.