Armstrong World Industries EHU-703 - Manual (Page 24)

Results:
-Excessive time needed to reach set point during star-up.
-Poor humidity control.
Remedy:
-Add 1/2 teaspoon of Epsom salts to the fill cup. After start-up the automatic drain program
should maintain the unit at full capacity.
-If problem persists, contact the factory.
WHEN WATER CONDUCTIVITY IS TOO HIGH
Indicators:
-Water level just touching tip of electrodes.
-Arcing and foaming in the tank.
-Frequent drain cycles (every time the fill valve opens) that last up to 10 seconds.
Results:
-Tank frequently needs cleaning.
-Poor control because of excessively low water level.
-Electrode destruction.
Remedies:
-If you have pure water available such as: de-ionized water, Reverse Osmosis diffusion water,
or distilled water, they can be blended with tap water to reduce the total mineral content. Pure
water alone is not conductive enough to pull current. The water is too pure when the "Tank
Full" light comes on excessively. Consult a water purification equipment vendor for the proper
blending equipment or the Armstrong factory for more information regarding use of purified
water. The blended water conductivity should be in the 200-400 μMhos/cm range.
-Softened water is not recommended for use with the Series EHU-700 Humidifiers.
Water softeners replace the calcium ions in the water with sodium ions. As softened water
boils, the sodium ions stay in solution causing the conductivity of the water in the tank to
increase rapidly.
CAUTION: Soft water may increase the tank's water conductivity and does not allow a
protective coating to form on electrodes. Also, as salts stay in solution more drainage
will be needed to maintain correct water conductivity in the tank. Please consult factory
for softened water analysis, if softened water source is available, before proceeding.
Expect to replace electrodes more frequently. Discontinue service if continuous arcing
or foaming occurs in the tank.
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