[MinVin]

I have a Pinot Grigio that had about 1 inch of headspace in the carboy, but now it has expanded up into the air lock. This wine finished fermentation and was degassed, stabilized and racked into this carboy around May 8. There is still air space between the wine and the water in the air lock and there is no leaking around the bung. I have this wine divided between a 5-Gal carboy and a 1-Gal jug - the jug wine has expanded similarly, but it hasn't gone quite as far up into the air lock.

My basement has warmed up to 75*F (unfortunate, but normal in the summer with the dehumidifier running). When originally racked into the carboy, the basement was around 60*F, but none of the other carboys (neither glass nor Better Bottles) are doing this. Over this past weekend we replaced our old dehumidifier with a bigger, more efficient one, so the humidity has also decreased over the last few days.

Is it a problem? Do I do anything or just wait and see? Any guess why only one out of 4 carboys (all different wines) under airlock are doing this?

[robie]

Is it foaming into the air lock or is the wine level itself up into the air lock?

If it is foam, it is either needing more degassing or it has started fermenting again.

If it is liquid, the change in temperature has changed the volume of the wine. Take a little out.

I can't say why it would happen to only one out of four.

[MinVin]

No foaming or bubbling, this is the wine itself.

In that case, I think I'll try setting it on the cold concrete floor for a while to see if it will chill down enough to reduce the volume and not make a mess (or waste wine!) when I pull the air lock/bung out.

[robie]

Take enough out to fill a 375 ml wine bottle (or a beer bottle) and safe it.
You don't want your wine up in the air lock.

[robie]

Or, take just enough out to give yourself an inch or more head space... drink the extra wine. If you let it set in a decanter for a couple of hours or freeze it for a couple of days, it will be tolerable.

[MinVin]

I've moved it down to the floor which is a bit cooler than the air. I'll let it stay there overnight and check it tomorrow. Then I'll remove some wine, whether it has gone down by then or not.

[MinVin]

In the past few hours, since I moved the wine to the floor, it has already cooled enough to be nearly out of the airlock. I should be able to open it up and remove some either later tonight or sometime tomorrow. All will be fine with the wine!

The sage advice from Douglas Adams comes to mind: DON'T PANIC

[ibglowin]

Sounds like the temp change and perhaps degassing on its own may have pushed up the volume and into the airlock.

You got it right, don't panic, pull the airlock out rinse, refill and drain the carboy down an inch or two and reseat the airlock.

[Flem]

Could the expansion be due to a barometric pressure change?

[MinVin]

I thought that at first, because I have seen slight fluctuations before that I attributed to baro press changes, but never this much and it lasted for a couple days - through our weather system changes - that's when I posted here.