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partially or wholly, for any purpose inconsistent with which it was produced. This information may not be reproduced or disclosed without prior
express consent.
9.5 System
Operation
The humidifier is an integral part of the HVAC System. The humidifier system is capable of
producing up to 12 pounds of steam per hour, at 15 amps. A sensor continually monitors the
interior of the mobile unit for relative humidity. This sensor is located in the HVAC return duct and is
programmed to keep the relative humidity at 50%. If the humidity drops below the set point, the
humidifier is signaled to emit more steam. The humidifier creates steam when electrodes in the
steam cylinder of the humidifier vaporize the supplied water. The steam then travels through a
hose to a distribution pipe located in the return air duct of the HVAC system. Since the steam is
injected into the return duct of the HVAC system, both A/C units are supplied with humidified air for
distribution throughout the interior of the mobile unit. If for any reason the airflow is disrupted, the
humidifier will shut down. When the sensor detects that relative humidity has been reached, a
signal is sent to the humidifier to stop it from creating more steam. The “Humidity Warning” light will
illuminate on the system panel if the humidity inside of the mobile unit becomes too high or too low.
If this happens, please refer to
9.6 Water
Supply
Water is supplied to the humidifier by means of an onboard water supply tank. The water supply
tank can only be filled from the outside of the mobile unit. Plumbing connections at the humidifier
are as follows:
1. A ¾” G.H.T. male threaded hose connection is located under the front kick of the mobile
unit, below the air conditioning units.
2. One 0.5” outer diameter PVC drain line from the steam cylinder for automatic drain cycles.
The drain penetrates the floor of the mobile unit in order to empty to the exterior.
3. One 0.5” outer diameter PVC drain line from the humidifier cabinet. The drain penetrates
the floor of the mobile unit in order to empty to the exterior.
4. One 0.5” outer diameter PVC overflow drain from the water supply tank. The drain
penetrates the floor of the mobile unit in order to empty to the exterior.
Figure 43: Humidifier External Water Connection
