Is the 3.5 ton N4A642GKB compatible with the 3.5 ton vertical cased coil END4X42L21A?

Yes the N4A642GKB is compatible with the END4X42L21A, but only when paired with an appropriate furnace will it be an AHRI-rated system. Without the furnace, it will not perform nearly as well. We have several systems with the two units already matched with appropriate furnaces on our site; use our search bar to find "N4A642GKB / END4X42L21A" and full furnace and AC systems containing the two units will show in the search results.

If you have any further questions, please call us and we will be happy to assist you.