How To Convert An Oil Furnace To Gas Or Propane—And Should You?

During the winter season, the thought of continuing the use of an oil furnace might seem daunting. Oil is a fuel source that isn't in use as much as it was once before. Many have moved on to using gas or propane furnaces for their heating needs. While searching for a new alternative, you might have the idea of converting your oil furnace to propane or gas. If you're wondering how to do it, we've researched this transition to get the answer for you. 

Converting from an oil furnace to gas or propane is a simple task. But, if you're not sure of what system you have, call a contractor to let you know. From there, the conversion from oil to gas or propane has a few requirements.

For an oil to gas conversion, they will need to run an extension from the mainline in your neighborhood to your furnace and home. An oil to propane conversion will require someone to install a propane tank on the side of your home or underground. 

There are still more details to discuss if you're seriously considering the switch. Two of the many reasons people convert to alternatives are cost and efficiency. Is there any support for these claims? Additionally, is it worth converting from oil to the other options? If you'd like to learn this and more, keep reading ahead. 

Propane Tank Outside Residence in Snowy Winter, How To Convert An Oil Furnace To Gas Or Propane—And Should You?

Converting from Oil to Gas

Let's get into the discussion of an oil to gas conversion. What's the main reason that might stop you from converting to gas? The difference between an oil furnace and a gas furnace is how you get the fuel to burn. Oil deliveries can come from the convenience of a truck. 

With a gas furnace, a utility company will have to route piping from the gas main under your street to your home. Depending on your situation, your area might not have a gas main to extend from. So, if you want to convert from oil to gas, there must be a gas main! 

In most cases, if you live in an urban or suburban area, there should be a gas main. However, if there's none present, you might have to convince the local utility to install a gas main with enough support from neighbors. From here, you can think about making the proper installations. 

Gas Furnace

Establishing the Connection

So, once you have access to the gas main in your area, the utility company will do most of the work. If you're wondering what work this includes, the utility company will run an underground pipe from the main to your home. Costs will range somewhere between $1,000-$1,500. However, they might waive the charge.

From here, a contractor will have to do the rest of the work. The final step would be to establish a connection from a meter to your heating plant.

Additional Work

Of course, the other part of the equation is whether you want to keep your existing equipment or replace it with a new one. You might also need to line your chimney.

A professional evaluation will tell you the rest of the work you need to do to ensure an easy conversion. Lastly, the type of system you have will also factor into the work professionals will have to do. 

For example, if you're switching from an electric baseboard heating or boiler system, a contractor must install ductworks and vents.  

Converting from Oil to Propane

Lifestyle, This shot shows a large propane fuel tank behind a residential building. The gas is used as fuel for home heating.

The next alternative is converting from oil to propane. This option is the next best thing for people who don't have access to a gas main. It costs more to use propane than gas. Nevertheless, it's an upgrade to any oil system. 

Converting from oil to propane is just as easy as converting from oil to gas. Though, getting the source of fuel is what differentiates the two (gas and propane). Old oil equipment will need to be replaced by proper propane facilities. In addition, professionals will need to install propane tanks outside of your home. 

However, the location of the tanks can depend on what size tank you choose. A 100-gallon propane tanks can be installed near your home. If you go with a 500-1,000 gallon tank, it can be installed underground or 10 feet away from your home. 


Another aspect that differentiates propane from gas is the need for ductwork. With propane, installers might go with direct venting. In other words, you won't need to line your chimney. The reason being, that propane units use air for combustion and send the exhaust outside. 

This method allows for more flexibility in the area where you will install the equipment. All in all, the conversion will take about three days to complete. If you'd like a video demonstrating the work an installer would have to do, here's a YouTube video briefly covering the work:

How Much Does It Cost To Convert an Oil Furnace to Gas?

You have finally decided to convert your oil furnace to gas but don’t know how much it will cost? Well, there is no one answer to this question. Everyone’s house is different with different conditions that impact the conversion cost. 

You can contact an expert to get the approximate cost. But in most cases, the average cost to convert an oil furnace to gas is around $5,000 to $10,000.

Furthermore, the following are some of the main factors that affect the cost of oil furnace to gas conversion cost.

Gas Line Length

The cost highly depends on the distance from the furnace to the gas meter. Also, if there is an object interfering with the installation, it can increase the cost.

Chimney Improvement

If you are living in an older house, then your current chimney might not be code-compliant. It means you would have to get a chimney improvement which will affect the overall cost of conversion.

Ductwork Improvement

Some old houses have inefficient ducts, which stop the homeowners from enjoying the full benefits of gas furnace to oil conversion. In cases like these, experts recommend getting your ductwork improved.

Good Quality Thermostat Installation

Most of the time, the pre-existing thermostat is working fine, but getting a good quality high-tech thermostat can help you lower your energy bills.

Is Gas Cheaper Than Oil Heating?

Different propane tanks, gas cylinders

Yes, gas heating is cheaper than oil heating. It is one of the main reasons why many homeowners switch from gas to oil furnaces. But why is gas heating cheaper than oil?

To start with, the cost of natural gas itself is lower than that of oil. So, even if we are solely looking at the cost, gas heating seems better in comparison.

Next up is the maintenance cost. If you have an oil furnace, you might already know how difficult it is to maintain. It costs around $300-$1,200 to get serviced.

Oil furnaces should be serviced at least once a year. If you live in a cold climate and use your furnace more often, the experts suggest getting it professionally cleaned twice a year. On the other hand, gas furnace maintenance not only costs lower, it only requires servicing once a year.

Can You Store Gas in an Oil Tank?

Home heating oil storage tank

No, you cannot store gas in an oil tank. Gasoline is a lightweight distillation that is not appropriate to use as a heating oil substitute. Putting gasoline in an oil tank can damage your furnace.

But what if you run out of heating oil and cannot get a refill? In cases like this, you can use diesel as a heating oil substitution. Heating oil and diesel are the most mid-weight distillations of petroleum. On top of that, both of these fuels produce almost the same amount of heat. 

Hence, diesel is a suitable substitute for heating oil. However, diesel is still just a substitute and should only be a last resort. Excessive usage of diesel in an oil tank can also damage your furnace. 

Is It Worth Converting From Oil to Propane?

Converting from oil to propane is not inexpensive. It can cost from $3,000-$8,000. This high cost makes many homeowners wonder if it is worth it.

In most cases, yes, converting from oil to propane heating is worth it. But, again, it depends on the cost of propane in your state mostly. Generally, propane is cheaper per BTU than heating oil in most of the states. It makes converting from oil to propane beneficial. But, the price of propane would be high if you live in a state with a propane shortage. 

In that case, you might have to stick with an oil furnace or consider going with gas.

Final Takeaway

Propane Tank Outside Residence in Snowy Winter, How To Convert An Oil Furnace To Gas Or Propane—And Should You?

Changing systems might be an easy transition or a nightmare that doesn't make sense. In some cases, you might want to keep your oil furnace because of a lack of access to gas or price differences between oil and propane. Regardless, we hope you found the information above helpful!

Before you go, do you have other oil furnace concerns? Are you planning on keeping your current system? Maintenance is an essential part of keeping it in tip-top shape! If you want to learn how long it takes to clean an oil furnace, check out our post here.

Did you decide on converting to a gas furnace? You might want to learn more about how to maintain this type of system. Check out our post here to learn how often to clean a natural gas furnace. Until next time!

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