What Happens If DEF Gets Too Hot? (These 4 Things Occur)

What Happens If DEF Gets Too Hot?

When you store or use Diesel Exhaust Fluid (DEF), it’s crucial to be aware of the temperature’s impact on its quality. DEF is essential for the Selective Catalytic Reduction (SCR) system in many diesel-powered vehicles, converting harmful nitrogen oxides into harmless nitrogen and water vapor. DEF consists of 32.5% urea and 67.5% deionized water. Here’s what can happen if your DEF gets too hot:

  • Urea Degradation: If your DEF heats beyond 86°F (30°C), its urea can start to degrade. This means it may not effectively reduce emissions anymore. If this happens, your vehicle might produce more NOx emissions or even limit its power to protect the engine and environment.
  • Decomposition: At extremely high temperatures, the urea in your DEF can break down into ammonia and isocyanic acid. This not only renders your DEF ineffective but can also damage the SCR catalyst in your vehicle. Replacing this catalyst can be quite expensive.
  • Crystallization or “Salting Out”: When DEF gets hot, the urea can crystallize and settle at the bottom. If these crystals get into the SCR system of your vehicle, they might clog it and cause malfunctions.
  • Reduced Shelf Life: While DEF generally has a shelf life of up to two years when stored correctly, exposure to high temperatures can reduce this lifespan significantly. Instead of lasting years, your DEF might only remain effective for a few months or even weeks.

So, when you’re storing your DEF, try to keep it in a cool, dry place away from direct sunlight. If you suspect your DEF has been compromised by heat or any other factor, it’s a good idea to replace it with a new batch to ensure your vehicle’s SCR system operates correctly.

Also, remember that while heat can be problematic for DEF, freezing temperatures can affect it too. DEF freezes at about 12°F (-11°C). If your DEF freezes, you can thaw and use it without any loss in its effectiveness. However, ensure your vehicle’s DEF system can handle and thaw the frozen fluid.

Read related article: Is It Cheaper to Get DEF at the Pump? (3 Best Advantages)

Seasonal Temperature Spikes Can Effect DEF

You might not be aware of how seasonal temperature changes can impact your DEF’s quality.

First off, let’s get to know what’s in your DEF. It’s a mix of 32.5% urea and 67.5% deionized water. This combination helps in minimizing harmful nitrogen oxide emissions from diesel engines. Keeping this blend stable is essential for both your vehicle’s performance and environmental compliance.

Hot Temperatures and Your DEF

As the summer sun beats down, the DEF in your vehicle or storage container might not be feeling so cool. High temperatures can cause the urea in DEF to degrade, especially if consistently exposed to conditions above 86°F (30°C).

In extreme heat, there’s a risk your DEF might break down into unwanted components, like ammonia, which won’t do any favors for the SCR catalyst in your vehicle. Additionally, you might notice urea crystallizing in hotter conditions. These crystals can potentially clog your SCR system, causing inefficiencies.

Also, think about the shelf life. Typically, DEF can last up to two years, but consistent heat exposure can dramatically reduce this timeframe.

The Cold Side of Things

Cold isn’t always kind to DEF either. During winter, your DEF can start to freeze when temperatures hover around 12°F (-11°C). Don’t worry too much, though; once thawed, your DEF is good to go. Just make sure your vehicle’s system can handle and defrost the fluid efficiently.

Storing DEF Amidst Seasonal Swings

Where you store your DEF can make a difference. In summers, find a cool, dry place, and during winters, try to keep it somewhere it won’t freeze constantly. Regularly check on your DEF, especially if it’s been through a few hot days or freezing nights. And if you’ve got a good stock of DEF, use the older containers first.

Being mindful of how temperatures affect your DEF can save you potential headaches down the road. Proper storage and awareness will help ensure your vehicle remains eco-friendly and performs at its best.

How to Protect DEF Fluid from High Temp?

Protecting your Diesel Exhaust Fluid from high temperatures is essential to keep it effective. Here’s how you can ensure your DEF stays in top condition even during hot days:

  • Choose the Right Storage Location: Ideally, you’d want to store your DEF indoors, especially in a climate-controlled environment. If that’s not an option, find a shaded spot outside. Direct sunlight can quickly heat up your DEF, so a little shade can make a significant difference.
  • Use Appropriate Containers: Consider using insulated DEF containers in areas that experience extreme heat. These containers help maintain a steady internal temperature. And it’s always a good idea to keep DEF in its original packaging. It’s designed to protect the fluid from external elements, including excessive heat.
  • Rotate Your DEF Stock: If you’ve got a stash of DEF containers, use the older ones first. DEF can degrade over time, especially in the heat, so it’s a good practice to use the oldest stock first to ensure its effectiveness isn’t compromised.
  • Keep an Eye on the Temperature: Think about investing in a temperature monitoring system for your DEF storage area. Some systems even send alerts if the temperature gets too high, giving you a heads up to take action.
  • Be Mindful When Transporting: If you’re moving DEF around, try to do it during the cooler parts of the day. And remember, don’t leave DEF in a vehicle that’s exposed to the sun for too long.
  • Ventilate the Storage Area: If your DEF is in a shed or storage room, make sure there’s good airflow. A well-ventilated area can help dissipate heat, keeping your DEF cooler.
  • Stay Informed: Knowledge is power. If you’re managing a fleet or just want to ensure your vehicle runs smoothly, educate yourself about DEF’s needs. The more you know, the better you can protect it.

Buy from Trusted Suppliers: Get your DEF from suppliers who have a reputation for quality. This way, you’re more likely to get a product that’s been properly stored and transported before it reaches you.

By following these guidelines, you’ll be better equipped to protect your DEF from high temperatures, ensuring your vehicle’s emission system remains efficient and eco-friendly. Read this OSHA letter for storage recommendation.

To Make a Conclusion

When it comes to Diesel Exhaust Fluid, understanding the implications of high temperatures is crucial for every vehicle owner. Excessive heat can compromise the quality of your DEF, leading to potential vehicle malfunctions and decreased eco-friendliness.

By being informed and proactive about how and where you store your DEF, especially during those hotter periods, you’re ensuring your vehicle’s optimal performance and upholding environmental standards. Always remember that a touch of awareness and some simple precautions can help you avoid complications in the future. So, even on the hottest days, keep your DEF’s well-being in mind to ensure your vehicle runs smoothly and efficiently.

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