Water way up blowoff tube?

[ltwhiskers]

So I brewed my Chimay Blue clone last weekend and when I checked on it a few days later I was surprised to find that water from the blowoff bowl I use was waaaay up in the tube (like 6 inches of water) reaching vertically out of the bowl up the tube leading back to the carboy. Also, no signs of fermentation yet, but the water in the tube was a first for me. This happen to anyone else? What's going on there?

 

[crispbrew]

When a closed system cools, air will become compressed creating a vacuum. As your wort cooled the air in your fermenter contracted, drawing up water through the blow off tube to make up the change in air volume.

 

[unionrdr]

The story gets better. When I've had that happen,I instinctively pulled up on the tube to let the water/Starsan mix out. Stuck the tube back in place & it bubbled right away.

 

[ltwhiskers]

Cool. Makes sense when you explain it that way. Tonight, after gently shaking and adding a few billion yeast cells yesterday, it is happily bubbling away.