I was thinking about putting central air in my house. Relatively small house-1050 sq. feet. One company told me that in order for the a.c. to work correctly I have to replace my furnance due to the horsepower not being high enough. They said I need to replace it from a .2 to a .3. Can't I just replace the motor instead of purchasing a new furnance. I am planning on selling the house within the next year. Hope this makes sense.