Totient and I are looking to replace our quarter-century old oil furnace with a modern system. The buzz-words for the thing we're thinking of getting include:
Mini-split (small units in each room, connecting to a single heating unit outside),
Multi-zone (separate controls for each unit),
Ceiling Cassette (vs wall-based), and
"Hyper Heat" or something similar ("Hyper Heat is Mitsubishi's word for the systems that can function down to -13F).
We're pretty sure this is the right answer for the third floor, but I don't want to sink boodle-bucks into something we've never seen, or, more importantly heard in use. How loud is it? Do you have a system similar to this? Does someone you know have one? Thanks!