I realise that you can't tell exactly without seeing and calculating but I don't know how to do that. I don't know what seer or tonage is.
It's a 2500 square foot house, two story rancher. The AC unit was installed after the build and is on the second floor in a horizontal position. Ducting was added for the purpose. The house is located in Maryland where it gets fairly hot and humid in the Summer. The heat exchanger is located outside and is the typical cylindrical, fan type unit.
Is that enough information for more knowledegable folks here to get me in the ballpark as to size, seer, tonage and cost?
Thanks in advance.