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Vertiv | Liebert PEX+ Chilled Water | User Manual
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System Operation and Maintenance
• Cut off the power supply before replacing the filter.
• It is recommended to set airflow switch according to the manual instructions, otherwise there will be
an air filter alarm or in the opposite case, the alarm could not be triggered by the dust accumulation on the
filter, endangering the system operation due to deteriorated ventilation.
• If you are unsure about the setting point, consult with Vertiv before using a filter of a different model to
replace the old one.
7.7. Fan
Regular check items of the fan include motor working status, fan blade status, fan assembly fixation, and the
clearance between the fan and the inlet ring.
Specially note that the fan components and the inlet ring are fixed firmly. Rotate the blades to ensure that they
do not scratch the adjacent metal plate. Any abnormal airflow obstruction should be immediately disposed, for
protecting the refrigeration system and other system components from airflow reduction.
7.8. Infrared Humidifier Maintenance Guide
During the normal operation of the infrared humidifier, sediment such as mineral particles will accumulate on
its water pan. To ensure efficient operation of the infrared humidifier, you need to clean the sediment regularly.
However, the cleansing cycle varies because the water quality is different in different regions. It is recommended
to check, and cleanse (when necessary) the water pan, once a month. The auto-flush function of the infrared
humidifier can prolong the cleansing cycle. However, regular checks and maintenance are necessary.
Cleaning Steps:
1. Remove the water level standpipe to drain the water pan.
2. Disconnect the drainage pipe.
3. Remove the safety switch of the water pan.
4. Remove the fixing screws at the two ends of the pan and pull out the water pan. Cleanse the water pan with
water and hard brush.
5. Restore the water pan by reversing the preceding procedures.
Before exercising the corresponding operation, ensure that the power supply has been switched off; also,
ensure that the water in the water pan is close to the room temperature before draining the water from the
infrared humidifier water pan to avoid the personal injury.