Recommendations for a/c repair or replacement?
I am a newish (1 year) homeowner. My a/c is not working well--the evaporator coils ice up after an hour of use and the blower stops blowing cold air. A local contractor came out and said that the blower motor, wheel, and capacitor need to be replaced. He also looked at the condenser outside and said that the fins are very degraded, probably because of dog urine. I don't have a dog--the previous owners did--the home inspector did not mention this problem and I didn't know what to look for. Now I do.
In order to get my system operational, I need a new blower motor, wheel, and capacitor (quoted $664). To increase the efficiency, I need to replace the outside condenser (quoted $2300 for a SEER13 dry charge unit filled with freon).
Should I replace the whole a/c system, including the evaporator coils inside? If I want to upgrade to a unit that is eligible for the tax credit, do I need to replace the furnace as well, or can I just replace the blower parts that are broken along with the condenser + evaporator coils to a system with a SEER 16 rating?
My current system is a 1995 Bryant a/c 3.5 ton (model 561CJ042-A with freon) and gas furnace (model 395CAV048111). I live in St. Louis, MO.