12 TROUBLESHOOTING AquaLab
3. Some products absorb or desorb moisture very slowly, causing
measurements to take longer than usual, and nothing can be
done to speed up the process. Refer to Section 8 for further
explanation.
4. Your sample may contain volatiles. Volatiles are known to
cause unstable readings, because they condense on the surface
of the chilled mirror and alter readings. Please refer to the
volatiles section in Section 8 for suggestions on reducing diffi-
culties with measuring samples with propylene glycol. If you
have further questions regarding the measurement of volatiles
contact Decagon.
5. A fan blade in the block chamber may be broken or bent. If
even salt standards take a long time to read, and the sample
chamber is clean, you may have a broken chamber fan blade.
This is especially likely if you have just cleaned the chamber.
If you suspect this may have happened, contact Decagon for
details on replacement.
3. PROBLEM:
Water activity readings on verification standards are too high/low
and a linear offset adjustment cannot be made any higher/lower.
SOLUTIONS:
1. The thermopile in your chamber, which measures sample tem-
perature, may have become contaminated. Refer to Section 6
for directions on cleaning.
2. The chamber mirror may be dirty. Refer to Section 6 for di-
rections on cleaning.
4. PROBLEM:
Message on screen displays a warning that the sample is too hot:
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