Close the
Isolate the humidifier from the electrical power supply at the main disconnect switch
SCALE MANAGEMENT
The gas humidifier will periodically “blowdown”
water from the tank to reduce the concentration of total dissolved solids that accumulate during long term operation. Gas Humidifiers are shipped factory set with a blowdown of 25%. This setting ensures that scale
Once the water conditions are known, the blowdown rate can be adjusted by software (GSTC models) or by using dip switches on the logic control board (GSP models).
Another effective means of controlling the amount of scale in the tank is with the use of the Full Tank Blowdown (FTBD) built into the software. When this feature is activated, the drain pump will be energized to drain the entire contents of the tank and then the tank will be refilled with fresh water, thus keeping the amount of total dissolved solids to a minimum. The feature can be programmed in the software to occur after a specific amount of operating time and can also be triggered by a signal sent to the humidifier from a building management system.
WATER QUALITY
Due to the wide range of water conditions found throughout North America it is important that the blowdown is set according to the local water conditions. By water conditions we are referring to the hardness of the water supplied to the humidifier. The hardness is measured in grains per gallon. It is also important to test for silica content. Silicates may cause foaming and contribute to scale buildup in the humidifier tank and float chamber.
If you are unaware of the hardness or silica content of your water supply, there are many “do it yourself” kits which can be purchased, or there are several companies that will perform the tests for a reasonable price. You can even contact your municipality for your water condition or order the NORTEC water test kit.
Figure #25
Site Water Test Kit P/N 1507214
Note: Water quality conditions resulting in component failures are not covered under NORTEC’s standard warranty.
Silica Test: Measured in ppm (parts per million) Follow the directions with the kit. A high reading will decrease the performance of your system. The recommended operating range for silica is 0 ppm to 14 ppm. Note: A high silica content along with a high hardness content may increase the service intervals of the system . Consult the factory if this condition exists at the site.
Hardness: Measured in gpg (grains per gallon). Follow the instructions on each individually wrapped test strip and use the colour chart provided. The recommended operating range for hardness is 0 gpg to 12 gpg. Note: High hardness along with high silica may increase the service intervals of the system. Consult the factory if this condition exists at the site.
pH: Follow the directions on the test strip bottle. The recommended operating range for pH is 6.5 to 7.5 on the colour scale. Consult the factory if outside these parameters.
Chlorides: Measured in ppm (parts per million). Follow the directions on the test strip bottle. The recommended level for chlorides is not to exceed 25 ppm.
NOTE: Failure due to chloride corrosion is not covred under Nortec’s standard warranty. Consult factory for more information.
High levels of chlorides will attack stainless steel. Consult the factory for additional information if your water contain high levels of chlorides.
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