How to Clean a Heating Oil Tank

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Not keeping your heating oil tank cleaned could lead to malfunction issues. Waking up without heat is not ideal, especially when you have a family in the winter months. You can clean a heating oil tank on your own, but it's usually best to have a professional do the job.

How to Clean a Heating Oil Tank
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Why Do Heating Oil Tanks Need Cleaning?

Sludge can accumulate in an oil tank over time. The problem with the sludge is it can clog the fuel line or the fuel filter. Sludge is a by-product of condensation that appears when the tank gets filled with oil that has a different temperature than the tank. What happens is the difference in the two temperatures will cause water vapor to condense, which leads to sludge formation. When you get fuel delivered to your tank, you can ask the technician if they notice any sludge. Usually, it's the technicians who notice the sludge before the homeowner.

How Often Should You Clean an Oil Tank?

To avoid any issues from sludge, schedule a fuel tank cleaning every three years. You may even be able to wait five years. The time frame depends on how much fuel you use annually, and the technician will help you determine an appropriate timeline for your tank. Not only does it matter how much fuel you use each year, but you should also receive frequent tank cleaning if you experienced any loose vent caps that allowed any insects, moisture or air in the tank. Additionally, when you don't let the oil level fall too low, it can help prevent sludge from entering the supply line or oil filter.

Cleaning Your Heating Oil Tank

Cleaning an oil tank can become quite messy. You will need the tank pumped out to perform the cleaning accurately. Handing this task off to the oil supplier is ideal.

If you feel you have the necessary background experience and want to try cleaning your oil tank on your own, you will need the following: disposable containers, cleaning rags, air hose, water hose, denatured alcohol, TSP cleaner and a portable air pump.

First, you will need to drain the tank. Grab a disposable container, and put it under the drain valve of the tank until all the oil is gone. A plastic container works best. When all the fuel is out, ensure a lid is on the container, and place it away from you, so it doesn't spill. Now, place a separate container beneath the drain valve and spray some water in the tank. Keep spraying water into the tank until you see clear liquid draining out. Place the cap back on the valve.

The second step is to clean the tank. When your tank is empty, fill it up with water, along with some trisodium phosphate cleaner. For every five gallons of water, use one cup of cleaner. Place an air hose into the tank and turn on your air pump. Let the solution work itself in the tank for 12 hours. Once the timeframe is up, open the drain valve and drain all the solution into a container. Next, spray the inside of the tank with water.

The last step is to dry your tank. You will want to ensure you get rid of all excess moisture as it could ruin the quality of fuel. Grab three gallons of denatured alcohol and pour it into your tank at different angles. You'll want to ensure all the walls have coating inside the tank. Next, place the air hose inside the tank and turn on the pump. Let the alcohol dry and run its process of absorbing all moisture. You can expect this process to take about an hour unless you have excess moisture. When all the moisture is gone, and your tank is completely dry, fill your tank back up with fuel.


Heather Burdo is a seasoned writer with six years of experience, including home improvement topics. Her passion is helping homeowners with tips and tricks through content.

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