Question: how much will it cost to replace my furnace and air conditioner?
Answer: Keep in mind that replacing a furnace on its own will cost around $2,000 to $5,000. Adding a furnace during your air conditioner replacement will cost a lot less, around $1,000 to $3,000. The only time it really makes sense to wait to replace your furnace is if it is less than 10 years old.