Floor and Wall Furnace Costs

• Gas floor furnaces that includes installation cost between $1,900 and $3,500, as of 2011. Gas wall furnaces that include installation cost between $1,500 and $3,500, depending on capacity and energy efficiency.
  
  

Mid-efficiency and High-efficiency Furnace Costs

• The cost of replacing older gas furnaces with mid-efficiency units is typically between $1,700 and $4,000 but can be more than $7,500, depending on complexity and location. Replacing older gas furnaces with a high-efficiency gas furnaces cost between $2,500 and $6,000 but can be more than $10,000, depending on complexity and location.
  
  

Fire Inspection and Chimney Liner Costs

• Your local government might require a fire inspection for a replacement furnace. It can cost between $25 and $75. Replacing an old furnace with a high-efficiency gas furnace may require installing a chimney liner, which may cost between $300 and $700.
  
  

Old Furnace Removal Cost

• Removing an old furnace from your home may cost between $500 and $1,500. That cost doubles with an underground oil tank. Additional expenses are asbestos removal from old duct work and installation of an air cleaner and a programmable thermostat.