image of water depicting heating oil tank with water

Oil heating systems depend on the home fuel tank for fuel storage and security. This arrangement runs well, but it isn’t a guarantee. There are times that water can get in the heating oil tank and cause issues, including oil tank condensation. This is a common but preventable problem.

Oil Tank Condensation: What You Need To Know

This article includes all you need to know about oil tank condensation and what you can do to prevent it.

How & Why Water Gets Into Your Home Oil Tank

Water is present everywhere in nature, taking various forms. It can slowly get into the tank as time passes. You can better prevent this from happening and recurring if you can determine how water got inside your oil tank.


image of rain depicting rain getting into home heating oil tank

A tank that is placed outdoors is exposed to rainwater. Water is a persistent element. It can squeeze inside narrow gaps and tight spaces, such as loose lids and caps. Tanks that are located near the house are susceptible to gutter overflows. Moreover, old oil tanks might have weak spots like cracked walls and damaged seals.


Regardless of the tank’s location, condensation is always a threat. The air vents pull in moist air from outside. Water vapor can turn to liquid if the inside temperature is low enough. Droplets can form in the interior wall of your tank and eventually drip to the bottom. A few water drops aren’t a big problem, but there is a great chance that the condensation will get worse over time when neglected.


Water can get in underground oil tanks if the container has holes around it. This is a concerning issue because water doesn’t just get in as oil also gets out and contaminates the soil. Call a professional HVAC technician when you’re dealing with underground damage.

What Happens If Water Gets into My Heating Oil Tank?

image of rust depicting inside of heating oil tank

Oil floats on water, so it is difficult to detect moisture using only observation. It is even harder to do so with an underground tank because it is hard to access. Water remains undetected for extended periods in many cases. The problem will only become apparent once symptoms start to emerge.

Being proactive in preventing problems is far better than dealing with water damage in the oil tank. Regular checks and maintenance can help save you from a lot of headaches. Routine inspections include using a water-finding paste to be placed at the bottom where water is likely to settle. Check the manufacturer’s recommendation or consult a heating oil expert regarding what paste to use. When the paste changes color, water is in the tank. A professional needs to resolve the issue immediately, especially if large amounts of water are present in the tank.

How To Prevent Heating Oil Tank Condensation

Focus your energy on preventing more water from entering your oil tank now that you know the possibilities. Here are some strategies you can do to do this:

Check the Fuel Oil Tank

heating oil tankCheck the tank’s exterior regularly. Look for any signs of damage like perforations, rust, and paint chips. Ensure all caps and lids are closed. If not, screw them tightly.

Test for Water

A visual check won’t be enough to determine if there is water in your tank, so test it for water periodically. Use a manufacturer-recommended water-finding paste or consult a heating oil professional. Try to reach the cylinder’s bottom. If you have an underground tank, you can test the soil for contamination.

Protect The Heating Oil Tank from Heat

Install the new tank under the shade and ensure that its exterior is painted with a color that reflects light to help with heat protection. This will lessen the chances of condensation inside the tank, which can occur from large temperature fluctuations outside the tank.

Keep Your Home Oil Tank Full

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Letting the level of fuel plummet to extremely low levels allows more moist air to get inside, increasing the chances of condensation. Schedule an oil delivery before this happens. Ensure that tank is full in both heating and off-seasons.

Call The Pros

Professionals will inspect your heating oil tank and replace old models when needed. Moreover, they can recommend the best placement to ensure long service life.

How to Remove the Water From Your Oil Tank

When the moisture test yields a positive result, you need to remove the standing water. This can be done in three ways. Make sure a professional handles this issue. Here are three steps a professional might take, depending on the situation:

Potential Damages of Not Removing Water From Your Oil Tank

image of an oil tank gauge and alarm

Here are the likely consequences when the water from your tank is not removed:

Oil Tank Rust

Some homeowners might think that water in the tank is harmless, so they ignore it. However, doing so can cause damage to your heating system after some time. For instance, water can corrode the oil tank walls. The majority of steel heating oil tanks rust from the inside. The cylinder might look perfectly fine from the outside when it is actually corroding from the inside. The walls weaken as a result, and you’ll have more problems down the road. This includes a decline in your system’s performance and efficiency.


Oil has a low freezing point. Therefore, it can sit in the cold during winter. This is unlike water, which freezes when the temperature drops to 32 degrees Fahrenheit or 0 degrees Celsius, which is a common occurrence in some places. Frozen water in tanks can block the oil supply pipes, resulting in system failure when your home needs heating the most.


Moist environments encourage bacteria growth. Water in oil tanks helps these microorganisms thrive and multiply. They can turn into sludge that forms at the bottom of the tank. They can release acid as well. This will quicken the corrosion in the tank, filters, burners, and fuel lines, causing significant problems.


Water shouldn’t be inside an oil tank. Ensure that water is kept out to prevent heating system problems and tank damage. Follow the preventative strategies above and consult a professional for advanced cases.

Call Tower Energy For Reliable Heating Oil Deliveries & HVAC Services

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Tower Energy is a local heating oil supplier that offers fast, friendly, and affordable fuel deliveries. We offer different delivery plans, including will call and automatic oil deliveries. We also provide our customers with many financing options so, essentially, you can customize your oil deliveries to meet your particular needs.

We also offer a full line of HVAC services. Some of those services include heating and cooling repairs, tune-ups, replacements, and more. We back all of our work with a guarantee to ensure your complete satisfaction. Our services aim to improve comfort, efficiency, indoor air quality, and much more. We offer free, in-home estimates. Give Tower Energy a call today to find out more.

Contact us now or call us at (860) 677-7347 to find out more.