My 1987 Coleman Heat Pump T.H.E.II heat pump air handler and thermostat are in good condition. I want to install a new outside 410 A system outside. I would also install new lines and a new coil in my inside unit. I would like recommendations at to the feasibility of doing this and which manufacturers to consider for the new equipment.

One manufacturer is about as good as the other. Most important part is a good experanced installer, get equipment with the best warranty, and a labor warranty, someone who has been around for a while and is going to stay around