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Old 03-29-2013, 03:45 PM   #1
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Default Varying OG Readings

I have an interesting problem. I boil 10 gal. batches in keggle with a recirculating pump. When I take gravity readings from the bottom of the kettle via the recirc line they are consistently 5-7 points lower than the readings when just skimming some wort of the top. These measurements are taken with both a calibrated hydrometer and refractometer. Both instruments reading match when taken from the same source. I always thought that 11 gallons of boiling wort would be pretty homogenous. Is there any chance that some stratification could be taking place or another reason I am getting varying, yet predicatable gravity readings?


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Old 04-01-2013, 03:57 PM   #2
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Are you letting the samples cool to room temperature before taking the measurements? I've noticed a 1°B change from hot to cold tap water with my refractometer which is about what you might expect with a hydrometer as well.


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