What Is That Whistling Sound During An Oil Delivery?

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Not many people are familiar with the process of filing an oil tank. The good news is that there’s not a lot to worry about. A trustworthy oil delivery company can guide you through every step of the way. Unlike what many might think, the process is very simple and quick, especially if your system is in good condition. During an oil delivery, you might notice a whistling sound coming from your heating oil tank. This may be alarming, but there’s really nothing to worry about. This whistle is a normal sound that the oil tank vent alarm makes. In other words, the whistling sound you’re hearing is a noise your system is supposed to make. To help you fully understand why this happens, keep reading.

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What Is That Whistling Sound During An Oil Delivery?

This article discusses the heating oil vent alarm and its importance during a fuel delivery.

The Source of The Sound During A Fuel Oil Delivery

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Whenever you call to have your heating oil delivered, oil delivery companies come with large trucks. A large hose allows the truck to connect to the fill pipe and send the oil down to the tank, which is connected to the heating system.

During the refill process, the oil tank vent alarm will then produce a very clear whistling sound that can be heard all the way to the delivery truck.

But why does this happen?

Whenever you use your heating system, the oil inside the tank is reduced, allowing air to take its place. Inside. During an oil delivery, the oil will take its place and push the air out. This air will then pass through that vent alarm, producing the whistling sound.

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When Will The Oil Tank Vent Alarm Stop Producing Sound?

The whistling will only continue as long as the air passes through the vent alarm on its way out. However, once the tank is full, the sound stops as when there isn’t any more air that needs to escape. When the delivery personnel no longer hears the sound, they will also stop the flow of oil from the truck.

This is the reason why the vent alarm exists. It’s a very reliable signal, indicating that the tank is full. Oil companies deliver oil to different homes with different oil tank sizes. On top of that, having this whistling sound is especially useful for tanks that are buried underground.

Why An Oil Tank Alarm Is Important

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As mentioned above, the tank vent alarm is very important as it helps determine how much oil the tank needs. It’s a safety precaution, and most heating oil companies have a policy where they won’t refill your tank when it doesn’t have a working oil tank vent alarm in place.

So how do they check?

Oil delivery personnel usually open the nozzle and let the liquid flow through, which should trigger the sound immediately. If the oil delivery company does not hear a sound heard, they will stop the flow. Otherwise, it can be hazardous as they won’t know whether the tank is filled or not.

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What If There Is No Sound During The Home Heating Oil Delivery?

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If your tank is not emitting a sound during a home heating oil delivery, then you might want to check the several reasons below:

  • Incorrect Connection: The first reason that your tank may lack a whistling sound is that your tank is not connected properly to the pipes. Yes, this might sound odd, but it’s possible. Two situations where this could happen are that (1) the tank might have already been excavated, but you weren’t aware of it, or (2) the connections were severed without you realizing it.
  • Damaged Seals: Another reason is that the tank is not sealed correctly. If there’s another opening where the air can escape before it reaches the vent alarm, then the oil tank vent alarm will not produce a whistle. It’s important that the flow must only be in one direction, which is through the vent pipe to trigger the alarm. If this is the problem, the issue needs to be sealed first before refiling the tank again.
  • Problematic Vent Pipe: It could also be that the vent pipe has problems. Insects might have built a nest inside, causing it to clog. When this happens, air pressure starts to build up, which can damage the tank. The clog must be removed first to provide better airflow in the pipes.
  • Broken Whistle: If you’re fortunate, then it could only be that the alarm itself has issues. It might have holes that allowed insects to get in, preventing any sound production. For this case, whatever is trapped in the hole must be unplugged so that air can pass through freely. After this, the alarm should not have any problems producing the required whistling sound.
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The delivery drivers at Wilcox Energy will check the tank if they don’t hear a whistling sound. We can also send technicians to visit your home and make the necessary repairs and replacements. If you have any questions about heating oil deliveries, feel free to give us a call, and we’ll be happy to answer any of your queries.

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Call Wilcox Energy For Reliable Heating Oil Tank Installations


For top-notch service and competitive prices on your heating oil and oil tank installations, contact Wilcox Energy as soon as possible.

We offer a broad range of financing options and delivery plans, which allow you to customize your oil deliveries to meet your specific needs. In addition, we perform heating system repairs and maintenance for the purpose of enhancing the overall efficiency and functionality of all your home heating equipment. Be sure to check out our TankSure® program, an oil tank protection plan to protect your investment. Contact Wilcox Energy for all of your residential heating needs.

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For more information about our heating oil deliveries, oil tank installations, or HVAC services, be sure to contact Wilcox Energy. You can click here to contact us or call us at (860) 399-6218. Call now!