gas boiler

Gas boilers use natural gas to heat water and distribute it through a network of pipes. The pipes can lead to radiators, a fan coil unit that heats the air, or to a radiant heating system, ultimately providing warmth and comfort in your home. Gas boilers produce more heat than an electric heating element, which makes them more efficient and eco-friendly than a system run by electricity.

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Is a Gas Boiler Right for You?

If you want to install a gas boiler, first be sure it makes sense for your home’s setup. Yes, they are the most efficient type of heating unit on the market—but if you don’t have a gas hookup, or if you already have an oil-fired boiler, the project will require more work and more spending. Removal of an old oil tank can cost you anywhere from $500 to $3000, while installing a gas hookup will cost you $1000 or more. You may also need to install a new chimney liner, which can easily cost upwards of $1000.

If your house isn’t an ideal candidate for a gas boiler for any of these reasons, the project could end up costing you thousands on top of the price tag of the unit and labor. However, the decision may be a bit easier if your home is a new construction, or if you’re retrofitting a house that is already connected to a gas line.

Standard Vs. High-Efficiency Gas Boilers

The annual fuel utilization efficiency, or AFUE, will be a very important number as you search for the right gas boiler. It represents the efficiency of the product. A standard gas boiler will have an AFUE of around an 80 to 85 percent and will cost you anywhere from $2000 to $5000. A high-efficiency boiler, which will have an AFUE upwards of 90 percent, will cost you between $5000 to $9000 to install. If you’re looking for a high-efficiency model, make sure you’ve taken a look at your heating bills and weighed the investment against the savings. When it’s time to start shopping, take a look at Energy Star-rated gas boilers, which meet government-mandated standards of efficiency.


For many home projects, it makes sense to shave down installation costs by doing the job yourself, even if it means learning along the way. But a poorly-installed gas boiler could jeopardize the safety of your family, and in some states it is illegal to perform this installation without a permit. You’ll also want help choosing the right size system, as a gas boiler with too large or too small of capacity will not be the most efficient for your home.

Professional installation for this project may cost upwards of a thousand dollars, which, understandably, many people consider an unnecessary financial sacrifice. But unless you have professional experience and the requisite permissions, it’s advisable to leave the labor to the contractor. Keep in mind the additional tasks besides assembling and hooking up the unit, such as removal of an old unit, gas hookup installation, pipe installation, building inspection, and chimney liner replacement. Call various contractors and ask for quotes on the project. Avoid choosing the most affordable contractor merely on principle—if your system isn’t installed correctly or you get the wrong size, you will either waste money on repairs or on poor performance.

Other Considerations

  • Pay more attention to the AFUE than the thermal efficiency rating. The thermal efficiency rating applies to ideal conditions, while the AFUE rating takes into account the reality of operating a gas—including temperature fluctuations and extreme temperatures.
  • A energy efficient heating system will only get you so far when it comes to saving money each month. Make sure your house is energy-optimized by sealing up cracks and holes, installing energy efficient windows, and improving insulation where needed.
  • While it may be an ordeal to switch from oil to gas, consider making this transition before replacing your oil-fired boiler. Oil-fired equipment is a good deal more expensive, and oil itself is pricier than natural gas.
  • If you suspect that your boiler could perform well again if repaired, look into repairing it rather than installing a new one. A repair will be much more affordable than a replacement.
  • Check to see if your project could qualify for a federal, state, or utility rebate. This could knock off some of the expense.

Have you recently installed a gas boiler? Share your experience with other readers in the comments below!