Abstract: A filter system includes a source of clean filter media adjacent a channel through which fluid passes. The filter media is automatically advanced from the source to the channel and eventually to a sealed container adjacent the channel. The filter media is automatically advanced through the channel, where it is replaced with clean filter media in the channel. A controller controls the advancement of the filter media based upon time or based upon a current condition of the filter media.

Abstract: A system is disclosed which incorporates low pressure drop contaminant removal from gas phases or streams, which advantageously can be used to enhance efficiency, improve humidity characteristics, and reduce capital cost of air handing systems such as HVAC systems and the like. Placement of the low pressure drop contaminant removal mechanism for enhancing effectiveness of same is also disclosed.

Abstract: In a fluid purification system, the same ultraviolet lights are used for both germicidal irradiation and photocatalytic oxidation. By positioning the ultraviolet lights where they can shine on both a heat transfer element (or other air handling system component) and onto a photocatalyst on a substrate, the total number of ultraviolet lights in the system is reduced, thereby reducing both the initial cost and the maintenance cost of periodically replacing the ultraviolet lights.

Abstract: An LED ultraviolet photocatalytic oxidation device is provided in a fluid handling system, such as an air handling system. In one embodiment, the photocatalyst is disposed on a protective layer (e.g. glass, plastic or quartz) on the semiconductor of the LED. In another embodiment, the photocatalyst is disposed on the protective layer, which is separated from the semiconductor by a fluid that filters or changes the wavelengths emitted by the LED. In a third embodiment, the photocatalyst is disposed directly on the semiconductor of the LED.

Abstract: A feedforward control method for an absorption chiller includes determining the disturbance transfer function, determining the capacity valve transfer function, measuring the actual disturbance, and implementing the feedforward control function in a feedforward controller. The feedforward control function is represented by the ratio of the disturbance transfer function divided by the capacity valve transfer function. The disturbance transfer function and the capacity valve transfer function are measured by applying a known amplitude input perturbation to the disturbance or capacity valve and recording the resulting perturbation in the output leaving chilled water temp. The disturbance transfer function is then the ratio of the delta leaving chilled water temperature divided by the delta change in the disturbance. The capacity transfer function is the ratio of the delta leaving chilled water temperature divided by the delta change in the capacity valve.

Abstract: An absorption refrigeration unit having a purge system that will sense when the discharge pressure of the solution pump becomes subatmospheric and will automatically increase the speed of the pump to bring the discharge pressure up to a desired level above atmospheric pressure so that a purging cycle can be achieved. The system further monitors the generation solution level and interrupts the purging cycle in the event the solution reaches an undesirable level.