pH meter problems

sdbrew1024 · 04-12-2011, 06:08 PM

I recently got a Hanna 98128 pH meter. The first thing I did was try to calibrate the meter. Unfortunately the 7.01 buffer reads 8.5 and the auto-cal won't recognize it. the 4.01 buffer reads about 5.5. I tried several other liquids with known pH values and they all read ~1.5 higher than they should. Is there anything I can do to fix this?

**BrewBeemer** · 04-12-2011, 07:12 PM

Quote:

Originally Posted by sdbrew1024

I recently got a Hanna 98128 pH meter. The first thing I did was try to calibrate the meter. Unfortunately the 7.01 buffer reads 8.5 and the auto-cal won't recognize it. the 4.01 buffer reads about 5.5. I tried several other liquids with known pH values and they all read ~1.5 higher than they should. Is there anything I can do to fix this?

Did you read the manual on it?http://www.hannainst.com/manuals/manHI_98127_98128.pdf

SpanishCastleAle · 04-12-2011, 07:23 PM

The manual for my Hanna pHep5 says to let it sit in the 7.01 solution for at least 30 min prior to using it for the first time. See if your manual says something like that.

sdbrew1024 · 04-12-2011, 08:19 PM

I did let the meter sit in the solution for some time, probably not a full 30 minutes, but around 20 or so... I didn't see anything about my specific issue in the manual.

I did read the manual, and during calibration I get the "WRNG" message. The manual states that this happens when a valid buffer is not recognized, but does not state what to do in this case. That is why I posted the question here.

BendBrewer · 04-12-2011, 08:22 PM

http://www.youtube.com/watch?v=cPbBZqgT4KQ

Check out the comments.

**BrewBeemer** · 04-12-2011, 08:30 PM

Didn't mean to sound harsh with the instructions. Your meter should auto set.
This a new meter 1st time ever used?
If it didn't respond even after a long soak as mentioned above I bet your "auto calibration" function is wacked out you have a bad meter.
Return exchange if possible.

I have a lesser Hanna unit with a fixed probe a 98107 that has a pH7 , pH 4/10 calibration screws on the requiring a jewelers screwdriver to calibrate.
Dang this is 9 years old still checks out accurately.
Good luck.