Author Topic: Equipment Boil off factor misleading, methinks.  (Read 6671 times)


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Equipment Boil off factor misleading, methinks.
« on: December 27, 2006, 07:24:11 PM »
In the section for evaporation rate the unit is expressed as %/hour. Isn't this misleading?

I mean at 10% per hour on a 5 gallon volume the figure would be .5 gallons.

But lets say you have a 10 gallon volume in the same kettle. The boil off would be the same .5 gallon per hour but the system would hold it to 10% of volume, Right, and assume 1 gallon per hour.

To simplify, shouldnt this be expressed as a volume evap. per hour expressed in factors of quarts or gallons and not a percentage. Say 1 gallon per hour as a constant regardless of actual boil volume.

Offline Yeasty

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Re: Equipment Boil off factor misleading, methinks.
« Reply #1 on: December 30, 2006, 12:30:11 AM »
I think you're right, FB. I guess it's an industry standard, though. Most folks boil for about 60-90 minutes, and so they figure they need to add an extra 15% in their kettle for their batch, but like you say if you have different volumes on the same system it won't calulate anything meaningful.
This might be an easy thing to change. Different SG worts will evaporate at different rates, not to mention relative humidity and wind factors. But if you could set it to say you lost about 3qt an hour that would help with getting preboil voumes and gravities.