My father has a carrier infinity furnace he wants to have central air added to the system. He lives in upstate NY so he probably would only use the system 2-3 months out of the year. His contractor told him that he needs to install the matching infinity condensing coil. This doesn't seem right he would like to spend less money and buy a brand such as goodman any thoughts
Sounds like you and Dad don't live close to one another so you're asking for someone here to make a guess as to what is right or wrong for your Dad's situation.
Best thing to do in a situation like this is to trust his contractors recommendation as they are the ones that will have to maintain and service the complete system and are the ones that know the entire situation the best.
As long as the condenser and coil are a matched set, I don't see why it has to be an Infinity or a even a Carrier for that matter. Maybe a Carrier Pro can chime in.
I believe that you have high electric rates in Upstate NY, so I would go 14 SEER (one step above bulider's grade 13 SEER).