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HVAC

Boiler Replacement and Installation

Average Cost:

$6,500 - $11,500

A dependable boiler keeps your home comfortable through long winters. In 2025, most homeowners spend $6,500 to $11,500 to replace a boiler, including equipment and professional installation. Your price depends on the boiler type (gas, oil, electric, combi, or steam), home size, venting and piping, and any extras like new radiators, zoning, or control upgrades.

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How Much Does Boiler Installation Cost?

Overall, expect a total project cost in the $6,500 to $11,500 range for many homes. Prices vary by fuel, efficiency, and complexity. Use the table below to compare typical installed costs by boiler type.

Boiler Replacement Costs by Type

Imported from Manual Input
Boiler TypeTypical Total CostWhat It’s Best For
Natural Gas (standard to high efficiency)$6,000 to $10,500Homes with gas service; balanced cost and efficiency
Oil$4,500 to $12,000Homes without gas lines; strong heat output
Electric$7,500 to $12,500All-electric homes, small spaces, easy installs
Combi (tankless heat + domestic hot water)$7,500 to $12,000Smaller to mid-size homes that want hot water and heat in one unit
Steam (radiator systems)$7,000 to $12,500Older homes with existing steam radiators
Solid Fuel (wood, pellets, coal)$8,500 to $15,000Rural properties with on-site fuel and storage space

Actual prices depend on boiler capacity, efficiency rating, venting, existing piping condition, and local labor rates.

Replacement Gas Boiler Cost

You’ll pay $6,000 to $10,500.

Gas boilers remain the most common choice where natural gas is available. Replacement often includes new venting (especially for high-efficiency condensing models), condensate drain setup, and system flushing. Ask your contractor to confirm the right size for your home. Oversizing can raise costs and reduce efficiency.

Oil Boiler Replacement Cost

You’ll pay $4,500 to $12,000.

Oil boilers serve many homes without gas service. Replacement may involve tank inspection or replacement, oil line upgrades, and nozzle/combustion tuning. Because oil prices fluctuate, consider efficiency and service availability when comparing models.

Cost of Installing a Combi Boiler

You’ll pay $7,500 to $12,000.

A combi boiler provides space heat and on-demand hot water in a single wall-hung unit. It can free up floor space and eliminate a separate water heater. You will pay more for higher hot-water flow rates. Sizing for both heating load and hot-water demand is key.

natural gas boiler in garage

Electric Boiler

You’ll pay $7,500 to $12,500.

Electric boilers are simple to install and nearly 100% efficient at the unit, but monthly bills depend on your electric rates. Check whether your electrical panel has capacity for the new load, and ask about off-peak rates from your utility.

Steam Boiler

You’ll pay $7,000 to $12,500.

Steam systems are durable and cozy but need steam-specific expertise. Replacement may include new near-boiler piping, proper venting, main and radiator vent checks, and water quality adjustments to protect the boiler.

Labor Cost to Replace a Boiler

Labor typically costs $2,000 to $5,000 of the total, depending on access, venting changes, piping complexity, and controls. Rates often fall between $90 and $150 per hour, with crew size and project scope affecting the final bill.

Factors That Affect Boiler Costs

  • Boiler Type and Efficiency: Condensing and higher-efficiency models cost more upfront but can lower bills.
  • Capacity (Size): Larger homes and higher hot-water needs require bigger, and more expensive, units.
  • Venting and Fuel Lines: New PVC venting, liners, or fuel-line updates add to your costs.
  • Piping and Radiators: Replacing valves, pumps, expansion tanks, or adding zones increases labor and materials.
  • Electrical and Controls: Smart thermostats, outdoor reset controls, and panel upgrades affect the total.
  • Access and Permits: Tight spaces, code updates, and inspections can add time and cost.

Boiler Repair Costs

Small fixes can extend your boiler’s life. Larger failures may justify replacement, especially with older units. Here are typical repair price ranges by issue or part.

Common Boiler Repairs and Typical Costs

Imported from Manual Input
Repair / PartTypical Cost
Circulator pump replacement$350 to $900
Expansion tank replacement$200 to $600
Pressure relief valve$150 to $400
Igniter or flame sensor$150 to $400
Thermostat replacement$150 to $500
Zone valve$200 to $500 per zone
Air vent / automatic bleeder$125 to $350
Aquastat or control board$300 to $900
Leak diagnosis and repair (minor)$250 to $750
System flush / water treatment$200 to $600
Heat exchanger (if replaceable)$1,200 to $3,000+

If repair costs approach 30% to 50% of a new system, especially on an older boiler, ask for a replacement quote as a comparison.

How to Save Money

  • Right-Size the Boiler: Ask for a load calculation to avoid oversizing.
  • Compare Two to Three Itemized Bids: Request line-by-line pricing for equipment, labor, venting, piping, and permits.
  • Bundle Smart Upgrades: Add outdoor reset controls, balancing, and basic insulation to improve comfort and reduce bills.
  • Schedule Off-Season: Spring and early fall can offer better availability and pricing.
  • Maintain Annually: A yearly tune-up protects efficiency, catches leaks early, and extends system life.
  • Ask About Rebates: Some utilities offer incentives for high-efficiency equipment or controls.

hot water heater

Next Steps

  • Decide on Fuel and Type: Gas, oil, or electric, and whether a combi unit fits your hot-water needs.
  • Check the System Around the Boiler: Radiators, pumps, valves, and vents may need attention too.
  • Get Local Quotes: Compare two to three itemized proposals that include equipment model numbers, warranties, and timelines.
  • Plan for the Future: Ask about expected lifespan, maintenance, and estimated annual fuel or electric costs.

If you’d like, we can connect you with pre-vetted local boiler pros to compare options, pricing, and schedules. We want to make sure you can choose the right system with confidence.

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FAQ

What is a boiler heater?

A boiler heats water by using natural gas, oil, electric or by burning solid fuels such as wood, coal and wood pellets as a fuel source. Once heated, the water is dispersed via an electric pump to carry heat to different types of home heating radiators installed throughout the home to provide heated water.


When should I replace home boiler?

Here are the signs that you should replace your home boiler heaters:



  • Frequent Breakdowns: Constant repairs can cost more than replacing the boiler.

  • Increased Energy Bills: Older systems consume more energy.

  • Uneven Heating: Difficulty maintaining consistent temperatures in your home.

  • Outdated Technology: New boiler installation can provide advanced features, including smart controls.


How to choose the right boiler replacement option?

When selecting a new boiler system, consider:



  • Fuel Type: Gas, electric, oil, or solid fuel.

  • Home Size: Larger homes may require more powerful systems.

  • Efficiency Ratings: Look for ENERGY STAR-certified models for maximum savings.

  • Professional Installation: Always hire licensed contractors for safe and efficient installation.


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