Ss Brewing Technologies Giveaway!

Home Brew Forums > Home Brewing Beer > Equipment/Sanitation > Refractometer reading swings high and low during boil
Reply
 
LinkBack Thread Tools
Old 08-14-2012, 06:06 PM   #1
BeerMoneyBrewing
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2012
Posts: 12
Liked 2 Times on 1 Posts

Default Refractometer reading swings high and low during boil

I'm getting almost a completely different Brix reading every time I use the refractometer, and what's strange is that it will actually lose points during the boil. Is this caused by the heat? Or possibly the hops? Anyone else experiencing similar issues?

Thanks

__________________
BeerMoneyBrewing is offline
 
Reply With Quote Quick reply to this message
Old 08-14-2012, 06:08 PM   #2
MalFet
/bɪər nərd/
HBT_LIFETIMESUPPORTER.png
Feedback Score: 1 reviews
 
MalFet's Avatar
Recipes 
 
Join Date: May 2010
Location: NYC / Kathmandu
Posts: 8,209
Liked 1235 Times on 821 Posts
Likes Given: 564

Default

Is your calibration screw loose? That's not normal. How does it compare to a hydro reading?

__________________

"Be excellent to each other." -Benjamin Franklin

MalFet is offline
 
Reply With Quote Quick reply to this message
Old 08-15-2012, 01:19 AM   #3
StanJohnson
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2011
Location: Titusville, Florida
Posts: 238
Liked 16 Times on 15 Posts
Likes Given: 46

Default

How much does your ambient temperature change? My instructions say to re-calibrate if ambient temperature changes by more than 5 degrees. I brew outside in Florida; so I am constantly re-calibrating throughout the brew day.

__________________

RDWIWBB

Stan

StanJohnson is offline
 
Reply With Quote Quick reply to this message
Old 08-16-2012, 05:16 AM   #4
pdxal
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jul 2010
Location: Portland, OR
Posts: 1,069
Liked 93 Times on 85 Posts
Likes Given: 136

Default

A lot of refractometers have automatic temperature correction. Maybe the samples are more/less dense depending on when or where you take the small sample from? This is a variation on the new brewers taking a hydrometer sample from the extract brew that hasn't been completely stirred to become uniform density...

__________________
pdxal is offline
 
Reply With Quote Quick reply to this message
Old 08-16-2012, 01:01 PM   #5
geniz
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: Georgia
Posts: 413
Liked 40 Times on 27 Posts
Likes Given: 4

Default

If its hot where youre brewing, and you store your refractometer inside, or if the temp increases during the day, your calibration is gonna change. I keep my refractometer in my ferm fridge at 68deg and keep my calibration dH2O there too.. I check my calibration several times during the day.

My refractometer is set to work at 20 deg C, so when Im brewing in a 85-90 deg F garage, my calibration goes way off.

__________________
BOHA Brewing Consortium

If Necessity is the Mother of Invention, Laziness is Its Creepy Uncle
geniz is offline
 
Reply With Quote Quick reply to this message
Old 08-17-2012, 02:21 AM   #6
eastoak
Senior Member
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2011
Location: oakland, california
Posts: 3,212
Liked 149 Times on 140 Posts
Likes Given: 83

Default

same thing happens with mine. i'll take a preboil reading, say 1050, then another 30 minutes into the boil and it will be way off, like 1075 or more. when i take a reading from the cooled wort going into the fermentor the readings are accurate. this is a pretty recent thing so maybe something has gone wrong with the thing.
.

__________________
eastoak is offline
 
Reply With Quote Quick reply to this message
Old 08-18-2012, 12:35 PM   #7
krazydave
Feedback Score: 1 reviews
Recipes 
 
Join Date: Aug 2010
Location: Santa Clarita, California
Posts: 872
Liked 24 Times on 22 Posts
Likes Given: 3

Default

I calibrate with multiple readings to make sure I have a good calibration right before my sample. Then I measure the sample over and over until I see three consistent readings. Only then will I trust what the refractometer is telling me.
Since I've started doing this, I've had zero questions of strange readings and my readings are usually a lot closer to what I'm expecting.

__________________
krazydave is offline
diS Likes This 
Reply With Quote Quick reply to this message
Old 08-18-2012, 12:57 PM   #8
diS
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Apr 2011
Location: Croatia
Posts: 1,018
Liked 45 Times on 43 Posts
Likes Given: 12

Default

Quote:
Originally Posted by krazydave View Post
I calibrate with multiple readings to make sure I have a good calibration right before my sample. Then I measure the sample over and over until I see three consistent readings. Only then will I trust what the refractometer is telling me.
Since I've started doing this, I've had zero questions of strange readings and my readings are usually a lot closer to what I'm expecting.
Great advice!
I have similar issue on my last batch (measures was 1 °P off in 5 minutes), pretty illogical... but when I took my hydrometer sample at the end of boil it matches refractometer reading.
I"ll do it your way next time.
__________________

We are only 10,000 years into beer... there are thousands of years left to go!
Things are bound to change!!

Brewroom with HERMS build
Fermentation chamber and Keezer.. a.k.a. FermKeezer

diS is offline
 
Reply With Quote Quick reply to this message
Old 08-18-2012, 01:54 PM   #9
nstnate
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jul 2012
Posts: 69
Liked 1 Times on 1 Posts
Likes Given: 1

Default

I have found that if I get my sample off of say my spoon it will vary a lot, but if I use the pipete that came with the refractometer it doesn't. I accredit it to evaperation of the hot wort before reaching the refractometer.

__________________
nstnate is online now
 
Reply With Quote Quick reply to this message
Old 08-18-2012, 02:05 PM   #10
Bobby_M
Vendor and Brewer
HBT_SPONSOR.png
Vendor Ads 
Feedback Score: 2 reviews
 
Bobby_M's Avatar
Recipes 
 
Join Date: Aug 2006
Location: Whitehouse Station, NJ
Posts: 22,020
Liked 983 Times on 655 Posts
Likes Given: 28

Default

Grab a few drops in a pipet, invert the pipet and dip the bulb in a small cup of icewater for 5 seconds. Dispense it on the refractometer.

Things mentioned already. Tiny hot wort samples will evaporate water quickly and change the gravity enough to be frustrating.

ATC is not a cure all for dumping any temp sample on the prism. ATC compensates for small shifts in ambient temps, not sample temps. While the prism has enough mass to pull sample temps down pretty close to ambient, it adds enough heat that the reading can shift as you watch.

__________________
BrewHardware.com
Sightglass, Refractometer, Ball Valve, Weldless bulkhead, Thermometer, Decals, Stainless Steel Fittings, Compression Fittings, Camlock Quick Disconnects, Scale, RIMS tube, Plate Chiller, Chugger Pump, Super Clear Silicone Tubing, and more!

New Stuff?
Bobby_M is offline
 
Reply With Quote Quick reply to this message
Reply



Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Refractometer and FG Reading baron Equipment/Sanitation 4 12-06-2011 04:25 PM
Refractometer - reading very low npauley88 Equipment/Sanitation 1 04-20-2011 01:07 AM
Refractometer reading goswell Equipment/Sanitation 7 06-12-2010 12:18 PM
Refractometer reading drifting up Stevorino Equipment/Sanitation 2 04-25-2010 08:57 PM
Reading a Refractometer Gammon N Beer Equipment/Sanitation 2 12-30-2008 10:29 PM