Does Adblue Freeze? Everything You Need to Know

AdBlue’s sole purpose is to reduce harmful emissions. However, because it is a fluid, you may be concerned about the possibility of it freezing, especially during the winter months. All your concerns are answered in this short article.

Can Adblue Freeze?

AdBlue, also known as diesel exhaust fluid (DE Fluid for short), can freeze. The freezing point of AdBlue is -11°C or 12°F. Although it can freeze, it only freezes in very cold temperatures, so depending on where you are in the world, you may never need to face this problem anyway.

However, regardless of AdBlue’s freezing temperatures, if it’s while it’s in its tank in the car, all AdBlue tanks have an internal heater that kicks in as soon as you start the engine. AdBlue will not be supplied to the Selective Catalytic Reduction (SCR for short) until it’s at the correct temperature anyway so that it does not cause damage.

What Happens When Adblue Freezes?

When AdBlue freezes, it expands and can damage the vehicle’s DEF system, but it’s rare. DE fluid freezing in the car becomes a big problem if the AdBlue heater fails to operate. If the heater fails, it can cause blockages, preventing AdBlue from spraying into the exhaust system to reduce vehicle emissions. The car will act the same as if you have run out of AdBlue.

This can cause the vehicle’s engine to go into limp mode or even shut down altogether. But this depends on the severity of the problem. At best, the engine management light will illuminate, and you shouldn’t continue driving until the AdBlue thaws. You can’t see the AdBlue in the tank in most vehicles, so you might not be able to see when it thaws. Even when you remove the filler cap the neck of the bottle can be quite long, so you will need to wait for an hour or two after ambient temperatures reach above its freezing point.

If AdBlue freezes while in storage, it will expand, potentially damaging the container and leaking when it thaws. You can safely thaw AdBlue by keeping it at average room temperature. Do not try to speed the speed up thawing by putting it next to a heater; if it gets too hot, it will damage the concentration of it.

does adblue freeze

How to Prevent Adblue From Freezing

When AdBlue is in the vehicle, to prevent it from freezing, the only way is to keep the car warm so parking in a garage when the temperatures will get below -11 degrees Celsius. If you don’t have a garage, I know that doesn’t help, so you will have to rely on the AdBlue in-tank heater to do its job when you next start the car.

Because AdBlue is readily available at most gas stations and lasts in the tank for around 10,000 miles in most vehicles, storing it is unnecessary. AdBlue has a shelf life and will go off. However, if you must, proper storage will prevent damage to the AdBlue solution and avoid freezing. Some tips include:

  • Store in a cool, dry place away from direct sunlight.
  • Keep containers sealed tightly to prevent contamination.
  • Use containers made of materials that are compatible with Adblue, such as high-density polyethylene (HDPE).
  • Do not store in containers that previously held other chemicals.
  • Label AdBlue containers clearly to avoid confusion with other substances.
  • Keep containers inside off the floor in the garage or shed.

Common Misconceptions About Preventing Adblue From Freezing?

There are a few misconceptions about preventing AdBlue from freezing. Some of them I find pretty amusing:

Adding more AdBlue will prevent it from freezing – This is false. Adding more AdBlue will not lower the freezing point.

Adding water to AdBlue will prevent it from freezing – This is false. Adding water will dilute the AdBlue and raise its freezing point.

Heating AdBlue will prevent it from freezing – This is true, but it is not a practical solution for most situations. The car already has its own AdBlue heater.

Adding antifreeze to AdBlue will prevent it from freezing – This is false. Antifreeze is incompatible with AdBlue and can cause damage to the SCR system.


AdBlue does have a risk of freezing in cold temperatures. However, you should not worry about this if the car’s AdBlue system works correctly. You can also minimize the chances of it freezing when it’s containers by ensuring that the AdBlue is appropriately stored.

It is recommended to store AdBlue in a location that is protected from extreme temperatures and sunlight. Additionally, it is crucial to use AdBlue, which meets the ISO 22241 standard; some cheaper, much weaker solutions may have a freezing point closer to water. While AdBlue freezing can cause issues with the SCR system, it is not common.

My name is Tom although my friends call me Tommy. Messing around with cars and bikes has always been a hobby of mine even from a young age. So I made it my day job 17 years ago. I am a fully qualified mechanic as you would expect. I've worked in all different areas of the motor trade, valeting, panel beating, engine repairs, I'm sure you get the idea. I enjoy sharing my wealth of knowledge and experience with others, which is the reason I spend a lot of time here writing for this website.

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