Oil-to-Gas Conversion Cost in New Hampshire: What to Expect
If you heat with oil, switching to gas can sound like a straightforward equipment change. Sometimes the work is fairly contained. Other homes need a new heating system, a fuel connection, different venting, and a plan for the old oil tank. Those are very different projects, even when both estimates say “oil-to-gas conversion.”
The cost to convert oil heat to gas in New Hampshire depends on what can stay, what needs to change, and whether natural gas is available at your address. The useful starting point is a complete scope of work. That gives you something you can actually compare.
What can you budget for the equipment and gas piping?
Our current installed heating-equipment ranges give you a starting point:
- Gas furnace: $3,875 to $7,900 for our standard through mid-tier options.
- High-efficiency gas furnace: $5,200 to $8,100, depending on size and equipment selection.
- Gas boiler: $8,500 to $15,000 for our standard through mid-tier options.
- Gas piping from the meter or propane regulator to the equipment: $1,200 to $4,000 when that work is needed.
The heating-equipment ranges include equipment, labor, permits, and standard installation accessories. They were checked September 10, 2026, and are before any rebate. The lower ends reflect discounted pricing; the actual equipment, work, and available pricing need to be confirmed in your proposal.
These are individual parts of a project, not a complete oil-to-gas conversion price. Choose the appropriate furnace or boiler option; you would not add all three equipment ranges together. Utility service, a propane supplier's tank and regulator, oil-tank removal, hot-water changes, or other work may be separate. The gas-piping range covers the piping downstream of the meter or regulator. A complete estimate needs to identify every part that applies to your house.
Start with which gas you mean
Natural gas comes through a utility connection. Propane is stored in a tank at the property. Both can be heating options, but they come with different fuel-supply arrangements and equipment requirements.
Before pricing a natural-gas conversion, confirm service availability with the utility for your exact address. A gas main elsewhere in town does not establish that your home can connect or what the connection would involve. If the house already has gas for another appliance, the utility still needs to review the additional load. Liberty explains this in its guidance on adding natural-gas equipment.
If natural gas is unavailable, compare propane and other appropriate options on their own merits. Our guide to choosing a heating fuel explains the broader decision.
What changes the conversion cost?
The equipment you have now
A furnace heats air and distributes it through ducts. A boiler heats water for the home's heating system. Converting the fuel does not mean you need to change the way heat reaches every room.
The existing equipment needs to be evaluated before anyone promises it can be converted. Its condition, manufacturer requirements, and suitability for the proposed fuel matter. Changing a burner on suitable equipment and installing an entirely new system should never be treated as the same scope.
The fuel supply and piping
The utility connection or propane-tank arrangement is one part of the project. The piping that supplies the equipment is another. The route, required capacity, other connected appliances, and access all affect the work. Ask who is responsible for each part and which charges are included in the estimate.
Venting, drainage, and electrical work
A new heating appliance may have different venting and combustion-air requirements from the old one. Condensate drainage, controls, wiring, and connections to the existing heating system also need to be included where required. The installation should follow the specific equipment instructions; an existing chimney or vent is not automatically suitable for a replacement appliance.
The old oil tank
Ask how the tank, remaining fuel, and associated piping will be handled. Where the tank sits and how it can be accessed matter. Any removal work should be identified in the estimate, along with the responsible party. Our oil-tank page is a useful starting point for discussing that part of the project.
Domestic hot water
Some oil boilers also help produce the home's hot water. If yours does, replacing the boiler affects more than the radiators or baseboard. The proposal needs to explain how you will get hot water afterward. Otherwise, an estimate can look complete while leaving out an important part of the house.
Compare the whole installation
Two quotes can use the same equipment brand and still cover different work. Before comparing the totals, look for:
- The proposed furnace or boiler and why its capacity fits the home.
- Fuel-supply responsibilities and any separate utility or supplier charges.
- Piping, venting, drainage, controls, and electrical work included.
- Oil-tank and old-equipment handling.
- The plan for domestic hot water, if the existing boiler provides it.
- Required permits, inspections, startup checks, and who handles them.
- Any exclusions or conditions that could change the price.
A good explanation should connect the recommendation to your home. If one quote is substantially different, ask what is included before assuming the equipment alone explains the difference.
Will switching fuels save money?
The installation cost and the operating cost are separate questions. A fuel change needs to be compared using fuel prices, equipment efficiency, and the amount of heat the house needs. A lower fuel price by itself does not tell you how quickly a project will pay for itself.
Use our heating-cost comparison calculator to explore operating-cost assumptions, then compare those results with an actual installation proposal. If you are already considering replacement, it can also be worth discussing whether a heat pump or a different heating arrangement fits the house.
Get an estimate that explains the work
At A.J. LeBlanc Heating, we want you to understand why something is being recommended. Start with the age and condition of your equipment, your comfort concerns, and the fuel options available at your property. From there, we can discuss the appropriate furnace or boiler installation and the work around it.
For an oil-to-gas conversion discussion in Southern New Hampshire, request an estimate or call 603-623-0412.
Common questions about oil-to-gas conversion
Can I get an accurate conversion price from my square footage?
Square footage alone leaves out equipment condition, fuel availability, venting, access, and the work needed to connect the new system. Those details need to be reviewed before an installed price is meaningful.
Do I have to replace all my baseboards or ductwork?
Not automatically. Existing distribution may be usable, depending on its condition and how the proposed equipment will work with it. The estimate should identify what can remain and explain any recommended changes.
Does a gas connection price include the heating installation?
Do not assume it does. Ask the utility, fuel supplier, and installing contractor to identify their responsibilities and charges so you can compare the full project cost.