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Hanna pH tester problem

Posted by floridabobx (My Page) on
Fri, Jul 4, 08 at 10:42


I recently attempted to upgrade from litmus paper to a meter for pH testing, but I'm having some trouble. I bought a HANNA 98108 pHep+.

I strictly followed all package instructions upon opening it, including letting it sit in pH 7.01 solution for 2 hours to activate the electrode.

However, it seems impossible to calibrate. After calibrating with 7.01 and 4.01 solution, within a minute it is off again, generally by a lot. When compared with the results of litmus paper, it is usually off by at least a full point immediately after calibration, but it varies greatly. When left to sit in 7.01 calibration solution, the reading slowly slides until after several minutes it may be up or down several points.

Am I missing something? Did I just get a bad unit?

Follow-Up Postings:

RE: Hanna pH tester problem

Sounds like your probe is faulty. I suggest you get back to your supplier. Hanna is a good make. I'm sure they'll fix the problem.

RE: Hanna pH tester problem

Yep, I agree with greystoke here. If your meter's reading drifts while sitting in the same solution there's something wrong with either the probe or the meter.

Talk to Hanna and see what they want to do to fix it.

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