Can I move a split AC indoor unit to a better spot, or add one to a room with none?

Short answer: yes to both — a split indoor unit can be relocated and a new split added to a room — but neither is a simple unscrew-and-move. Both are proper installation jobs because the three things behind the unit have to move/route with it: the refrigerant pipework, the condensate drain, and the power. Get those right and it's clean; get the drain wrong and it drips.

Relocating an existing indoor unit: - New pipe route to the outdoor unit (re-run/extend the insulated copper lines — longer runs may need a gas top-up and proper re-flare). - New condensate drain run with correct fall to a drain point — this is the one people botch; a drain without proper fall means the classic ceiling/wall drip. - Making good the old holes and the wall.

Adding a new split to a room with none: - Space and a route for the outdoor condenser, the pipework through the wall, a drain, and — importantly — power: a new unit needs a supply and often its own breaker/circuit, so the board has to have capacity (a licensed-electrician touchpoint). - Size the new unit for the room (see the AC sizing principles — don't guess).

Renter note: relocating/adding is a fixed alteration — get landlord permission first.

Common mistakes: a too-long pipe run left un-topped-up (weak cooling), and a condensate drain without fall (drips). Both are why it's an AC installation job, not a handyman move. The blow-on-the-sofa one is often solved just by relocating a metre or angling the louvres — worth asking whether a full move is even needed. What did people's relocations cost in effort — big job or half a day?