Today I got a new refrigerator carbon water filter (this). Before installing, out of curiosity, I dripped a bit tap water into the filter’s outlet to see if water could flow in and out. Obviously it did… Then, distracted by something else, I put the cap back on the filter and walked away. Several minutes later I heard a fairly loud pop sound. The cap popped out. So the filter must have been building up air pressure inside. I wonder how. Does it have anything to do how activated carbon interact with water? Any ideas?
2 Answers
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The filter may have come from a cooler environment, so the higher ambient temperature caused the air to expand that was inside the filter as the temperature equalised..
As you had sealed the inlet & outlet with a cap then the pressure increased until it overcame the friction holding one of the caps.
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the water wetted the filter over a large area inside it. the water then began to evaporate in an effort to saturate the air inside the filter housing at the temperature of the housing. The pressure rise then blew off the cap.
