My Carter lid is sealed tight and I can't open it! What do I do? My Carter lid is sealed tight and I can't open it! What do I do?

My Carter lid is sealed tight and I can't open it! What do I do?

It's no fun when you can't access your coffee (or other drink of choice, no judgment here), but there's no need to worry. With some patience and a little science, you can get that Carter open again! 

Why it happens

In most cases, this strong seal is a result of a hot liquid cooling over time inside a sealed container. When the container is sealed and the contents start to cool down, the air inside the container actually contracts. As a result, the pressure inside the container decreases compared to the external atmospheric pressure. This generally happens if hot liquid is topped off and then sealed. The absence of air creates a vacuum inside the container

How to get your Carter open again

To weaken the vacuum lock, the contents need to be reheated inside the container. For a Carter, we recommend heating it slowly over the course of a long time to achieve this without damaging it.

If you're using the mug for boiling or near-boiling liquids in the future, we recommend letting it cool for a few seconds before applying the lid. This will prevent the seal from reforming.

As always, please don't hesitate to reach out to us if you have any questions or need help!

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