Troubleshooting
Initial Startup
On initial startup, the inside surface of the copper electrode should be cleaned BEFORE any calibration
is done, due to the rapid oxidation that takes place on pure copper.
Trimmer Adjustment
All the trimmers used on the analyzer are of the 30-turn variety, so it may take several turns before
you get the desired residual setting or voltage.
ZERO and Std. Interaction
The ZERO and Std. settings do interact with each other, so adjusting one setting may affect the other.
You may have to go back and forth a couple of times between ZERO and Std. to get the calibration
correct.
Water Sample with Contaminates
Make sure the water sample does not contain any oils, grease, or corrosion inhibitors that would coat
the inside of the measuring cell, and inhibit the electrical properties of the cell.
Proper Sample Flow
Check the sample flow. There should be ample flow, so that there is a constant overflow from both
drains, especially the left one, which is the drain from the sample cell. The left drain should flow at
about 120 ml per minute. If there is little or no flow from the left drain, check for a blockage in the flow
tube, located under the inlet sample weir, sandwiched between the upper and lower blocks. Check
for air bubbles in cell inlet. Use a small screwdriver or piece of wire. Insert it into sample flow inlet. If a
good flow starts, then air bubbles are the issue. Install flow regulator fitting supplied with the analyzer.
Proper Vinegar Feed
Check the vinegar feed. The analyzer should use about one gallon of vinegar every 4 1/2 days, on
the #14 peristaltic tubing. If you are using the #13 tubing (assuming the sample is within proper pH
and total alkalinity limits), you should use one gallon of vinegar in about 13 days. For quick check,
pull the flushing plug out of the small block and observe the drip from the end of the flushing plug. It
should feed a full drop about every 3 to 4 seconds. For a more accurate check, pull the vinegar from
a graduated beaker, and time the feed rate.
Peristaltic Pump
Check the peristaltic pump. If the occlusion ring on the peristaltic pump is loose, the rollers cannot
fully pinch the tubing, which can cause vinegar siphoning (too much buffer) or little or no vinegar feed,
depending where the vinegar bottle wall bracket is mounted. This can also happen on units that are
several years old and have been subject to more pump head bearing wear, creating a larger gap between
the rollers and the occlusion ring.
The tubing is quite resilient and should last for several years. If the tubing develops a flat-spot where
it sits in the pump head, and does not feed correctly, try loosening the tubing clamp and occlusion ring
to move the flat-spot out of the pump head so that there is a fresh section of tubing in the pump head.
Replace tubing to achieve proper flow.
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