2019 Average Oil Boiler Installation Prices: How Much â
Oil Boiler Average Costs . The actual cost of an oil boiler depends on the size of the system, the unit's AFUE rating, your location, the difficulty of the installation, and other factors. Mid-efficiency oil boiler replacement cost should be $2,500 to $5,000 installed. Installing a high-efficiency oil boiler might cost $5,000 to $10,000 or more.