The most popular air conditioning system is central air. This is where a special fluid called a refrigerant circulates between an indoor coil and an outdoor condenser with a compressor. The refrigerant cools and dehumidifies the air and then the air is blown through ducts into the house.
Your climate and cooling loads will dictate the type and size of which air conditioner you’ll need. When you start looking for a central air conditioner, look for a SEER (seasonal energy efficiency ratio) rating between 12-20.
If you are planning to have a forced-air heating system, you may be able to tie an air conditioner into your existing ducts, but that will depend on their size and your home’s relative heating and cooling loads. Keep in mind that the price tag for cool air using this system is quite costly — not only the system itself, which starts around $5,000 installed, but also your electric bill. For comfort and resale purposes, AC systems are definitely worth the investment.