Re: Installing Central Air in My Old House
IS this a single story ranch, or a 1 story? Size? Where are you located? First and foremost it needs to be sized correctly. Properly sized equipment can operate up to 30% more efficient than oversized equipment. More than 50% of AC systems in the US are estimated to be oversized. I cut my cooling bill upstairs by over 60% by downsizing and installing efficient 2 stage equipment.
Find a contractor which will do a load calculation and will do proper ductwork sizing. This is 100x more important than what brand, and needs ot be factored into pricing. If they use a "guess" based off experience, you have a 50/50 shot at best if it's sized and installed correctly.
IF it's single story, you can put the air handler in the attic but make sure the ductwork is well insulated and sealed. Then you just cut the correct size and number of registers in the ceiling of each room. Depending on heating fuel costs, (electric vs. gas) you can also put in a heat pump for mild weather (above 35-40F) that will use less energy and not overheat the space like a boiler can.
2nd option is a ductless minisplit system with multiple indoor units. One in each room.
1925 Two-Story Stucco Beaux Arts Neoclassical