Refilling 16 oz propane bottle off a 20# tank

Leave the pot in the sunlight for awhile. Store the empty cylinders in the freezer for 4-hours. The pressure differential insures the pot will be filled within 10-seconds. Use a scale. With tare. Overfilled bottles will indeed go overpressure and vent if overfilled and temperatures climb. The 16 oz limit is hard and fixed. If you want to play games, guess, and overfill bottles, please park far away from me. I have seen idiot-guesswork filled bottles that had failed relief valves. The bottles were bulged. This is a certain death-wish. When most gasses violently expand there exists a high probability of inherent static electricity.

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