I had a 220 outlet for a a/c unit and my landkord change it to a 110v for smaller unit. Now we want to change it to a 230v 15 amp. For a a/c unit what do I need to do.

I had a 220 outlet an change it to a 110 for a smaller a/c uit and now we want to change it to a 230v 15 amp . What do I need t do.

Call your landlord. You might not legally be allowed to do this without the LL permission. This opens other liabilities as well so you might want the LL to do it anyway...

Amen.

Call your LL, period. You cannot do with work, even with his permission.