Hey William, so the Advent Air AC unit part # ADV64FR would be a solid 15k BTU rated replaced for your setup. It is designed for ducted applications like you'd need as well. This also will wire right up to Advent and Dometic setups but if you have a Coleman kit currently you'd want the part # ACCOLKIT or the Carrier part # ACCARKIT to give you ability to have a plug and play wiring install. view full answer...