Air temp vs. actual temp of beer in fermenter
I have 14 bbl fermenting vessels and on occassion I only fill them with 7bbl worth of wort. This is traditionally only when I brew big beer i.e. barley wine, scotch ale and the subsequent second runnings. The temperature probes unfortunately are in the straight side of the tank verus the cone so the beer doesn't always reach the probe for an accurate reading. The zwickel is also higher on the tank than the beer level itself. I'm relying on the air temp inside the vessel for temperature control. So is there any formula or good estimation that can be used to get the liquid temperature in a vessel based upon air temperature and empty space? I'd like to have an idea of how low I can drop temperature without freezing?
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