TIL the hard way about propane regulator freeze-up at a demo

I was doing a live forging demo at the county fair last August. Temp was around 85 degrees but the humidity was through the roof. About 20 minutes in my forge flame started sputtering and dying. I thought I was out of propane but the tank was still 3/4 full. Turns out high humidity can cause vapor lock in the regulator when you're drawing gas too fast. It cost me 45 minutes of downtime while the whole crowd watched me swap tanks and mess with fittings. Has anyone else run into this or found a fix for high flow days?

2 comments

2 Comments

barbarahill1mo ago

Actually, you’re describing a regulator icing issue, not vapor lock. Vapor lock is a fuel problem in engines where liquid gas gets too hot and turns to vapor, while regulator freeze-up happens when propane expands quickly and chills the metal, letting moisture freeze inside. High humidity makes that much worse, which is what hit you at the fair.

fiona3321mo ago

Exactly, the humidity factor is what really seals it as regulator icing. A lot of folks don't realize how much moisture in the air can accelerate that freeze-up, especially during summer fairs or events. Your mileage may vary on how often it happens, but once you've dealt with it, you never forget that hissing sound.