How Long Do Fuel Oil Tanks Last?

Fuel oil tanks don't last forever, and replacing them is a crucial investment. The average fuel oil tank lasts between 15 and 20 years, but some can last longer with proper maintenance. However, the Maryland Department of the Environment recommends replacing them approximately every 15 years to avoid problems associated with ageing. If you're unsure about your oil tank's age, it's best to schedule an inspection by a professional who can detect potential problems and advise on repairs or replacement. Waiting for a tank to fail can be costly, as it may lead to hazardous situations and costly cleanups. Some signs that your oil tank needs attention include rust, dents, wet spots, unstable legs, faulty vent alarms, broken fuel gauges, leaks, and unprotected oil lines.

Oil tank lifespan

Oil tanks don't last forever, and it's important to replace them before they fail to avoid a hazardous and costly situation. On average, a fuel oil tank lasts between 15 and 20 years, although some can last longer with proper maintenance. The Maryland Department of the Environment recommends that homeowners plan to replace their oil tank approximately every 15 years.

If you're unsure about your oil tank's age, it's best to schedule a tank inspection by a professional. They can detect potential problems and advise on repairs or replacement. Age isn't the only factor, as tanks unprotected from the elements or those that aren't properly maintained will likely have problems sooner.

• Visible signs of exterior damage: Regularly inspect the exterior of your above-ground oil tank for corrosion, rust, discolouration, or denting. If there is enough damage to be visible on the outside, the inside is likely to be substantially worse.
• Exposure to elements: If your oil tank is outdoors, ensure that no elements, especially snow or ice, can get inside. Snowfall can be extremely damaging to oil tanks and can lead to the need for replacement.
• Weak or unstable legs: The legs supporting your oil tank can reflect its overall condition. While it is possible to replace the legs, it may be better to replace the entire tank.
• Damaged or broken components: A broken fuel gauge or faulty oil tank vent alarm can cause trouble and reduce safety. If the vent alarm is broken, an oil delivery supplier will not fill the tank, risking a heating emergency.
• Wet spots and other signs of leaking: Pinholes and minor cracks are often the first signs of internal corrosion. Wet spots or puddles of oil around the tank or piping, a persistent heating oil odour, or drops in heating oil efficiency may indicate a leak.
• Unprotected oil lines: The oil lines connecting the tank to the furnace should be in good condition. If you notice any splits or cracks, have a technician service the tank immediately, as an oil leak may be imminent.

To extend the lifespan of your oil tank, regularly inspect it for damage, especially during peak usage months. Keep the tank clear of snow, ice, and debris, and ensure no icicles can fall onto it. Schedule regular maintenance with a technician, who can identify problems and advise on replacements.

Signs of damage

The most common cause of heating oil tank failure is internal corrosion, which is often the result of condensation. This is hard to spot, but there are some signs of damage to look out for.

Firstly, check for pinhole leaks or loose oil around your tank. If you see any liquid on the tank itself or the ground below, there is likely a leak. This is a serious issue, as it can cost you a lot of money in wasted fuel oil and cause environmental damage.

Secondly, look for signs of corrosion and/or rust on the underside of the tank. If there is rust on the outside, there is likely to be more on the inside, which could lead to clogged fuel lines and filters, preventing your heating system from working properly.

Thirdly, check for persistent wet spots on the outside of the tank after a heating oil delivery. This could indicate a problem with the tank.

Other signs of damage include dents, which could indicate a more serious internal problem, and blistering on the tank's exterior, especially along the bottom.

If your tank is more than 15 years old, it is a good idea to have a professional inspect it for signs of wear and potential future performance issues.

Tank inspection

• Schedule Regular Inspections: It is recommended to have your oil tank inspected regularly, especially if it is more than 15 years old. Schedule inspections with a qualified technician who can identify potential problems and recommend repairs or replacement.
• Check for External Damage: Inspect the exterior of your oil tank for any signs of damage, such as corrosion, rust, discoloration, or denting. If there is significant external damage, it is likely that the inside of the tank is also damaged and may need to be replaced.
• Look for Leaks: One of the most common issues with oil tanks is leaking. Check for wet spots around the tank or puddles of oil near the tank or its piping. Even minor cracks or pinholes can lead to significant leaks over time.
• Unstable or Weak Legs: The legs supporting your oil tank can reflect the overall condition of the tank. If the legs appear unstable or weak, it may be a sign that the tank needs to be replaced. In some cases, you may only need to replace the legs, but often it is better to replace the entire tank.
• Damage to Components: A broken fuel gauge or a faulty oil tank vent alarm can cause issues and reduce the safety of your heating system. Remember, a broken vent alarm may prevent an oil delivery, so it's important to get it fixed promptly.
• Exposure to Elements: If your oil tank is located outdoors, ensure that it is protected from the elements, especially snow and ice. Exposure to snowfall can be extremely damaging to an oil tank and may require replacement.
• Oil Inefficiency: If you're using oil faster than usual, it could be a sign that your tank is leaking or has other issues. Have a technician inspect the tank to identify the cause of the inefficiency.
• Unprotected Oil Lines: Inspect the oil lines connecting the tank to the furnace for any splits or cracks. If the oil lines are damaged, it could lead to an oil leak, and you should contact a technician for servicing.
• Internal Problems: Oil tanks can develop internal problems over time, such as trapped moisture and sediment buildup, which can lead to tiny holes forming in the tank and eventual oil leaks. Unfortunately, these issues can be difficult to identify without proper equipment.
• Age of the Tank: The average lifespan of an oil tank is around 15 to 20 years for underground tanks and 25 to 30 years for aboveground tanks. If your tank is approaching or exceeding this age range, it's recommended to have it inspected more frequently and consider replacement.

Preventing leaks

The best way to prevent leaks is to be vigilant about inspecting your oil tank and scheduling regular maintenance. Check the stability of the legs of your tank to make sure they haven't buckled under years of use. Inspect the ground or flooring around your aboveground tank for any signs of leakage. If you have an underground tank, take a soil sample to check for oil contamination.

It's also important to keep your tank full, especially during spring and summer. This helps protect your tank from condensation damage. If a tank is not filled entirely, it can lead to moisture buildup on the interior walls, which can result in condensation formation and, eventually, corrosion.

Make sure all the pipe connections are clean and tight. Loose connections between sections of fuel oil pipes are a common reason for spills. Place all the fuel oil lines that run from the tank to the furnace under concrete or in protective tubing to prevent accidental damage.

If your tank is more than 20 years old, it's time to start planning for a replacement. Tanks over 20 years old are more susceptible to corrosion and other damage, which can lead to leaks.

You should also consider investing in a smarter and safer tank design. Corrosion-resistant fiberglass, double-walled, or double-bottom tank designs can help prevent spills and leaks and save you money in clean-up costs.

Finally, schedule regular maintenance—at least yearly and before the start of any season that will require you to heat your home. Maintenance is the best way to prevent an oil spill or leak.

Replacement options

If your oil tank is approaching the end of its lifespan, or you've noticed signs of damage, it's important to start considering your replacement options. Here are some things to keep in mind:

Timing: Oil tanks typically last between 15 and 20 years, although some can last longer with proper maintenance. It's recommended that you inspect your tank by its 15th year and plan for a replacement to avoid any unexpected issues or costs. Summer is an ideal time to replace your oil tank as the demand for equipment service is lower, allowing for a quicker installation.

Professional Inspection: While you can inspect your oil tank for visible signs of damage, it's always best to consult a professional technician. They can spot potential problems that homeowners may miss, such as interior rust or small cracks that can lead to leaks. A licensed technician will be able to diagnose the problem and recommend the best course of action, whether it's repairing or replacing the tank.

Cost Considerations: The cost of oil tank replacement can vary depending on several factors, including the proximity to the furnace and any additional services required, such as pumping leftover oil or cutting new lines. On average, the installation of a double-walled oil tank can range from $1,000 to $4,000. However, it's important to get an accurate estimate from a professional company to understand the total cost.

Preventative Measures: Replacing your oil tank proactively can help protect your furnace, avoid tank failure, boost safety, and conserve energy. A new tank will not have the same internal problems as an older tank, reducing the risk of leaks or ruptures. Additionally, newer tanks often have improved stability and better insulation, reducing the chances of clogging and erosion.

Maintenance: To extend the life of your new oil tank, it's important to perform regular maintenance and inspections. Keep the area around the tank clear of debris and snow, and ensure no ice or snow is building up on the tank itself. Schedule annual maintenance visits from a technician to identify any potential problems and ensure optimal performance.

Frequently asked questions