Water recirculation system

A cooling system comprising:

• a cooling coil configured to pass an internal fluid;
• an evaporative pad positioned relative to a cooling coil;
• an airflow generator arranged to draw air through the evaporative pad and over the cooling coil;
• and
• a liquid distribution system comprising:
• an inlet configured to allow evaporative liquid into the liquid distribution system;
• a dispenser positioned to distribute evaporative liquid over the evaporative pad;
• a make-up valve that regulates the flow of evaporative liquid between the inlet and the dispenser;
• a sump positioned to collect evaporative liquid that runs off the evaporative pad, the sump including a drain valve and a level sensor,
• a pump in fluid communication with the sump and the dispenser;
• and
• a controller in communication with the airflow generator, the drain valve, the level sensor, and the liquid distribution system,
• wherein the controller is configured to control the liquid distribution system to operate among one of a plurality of operating modes, the plurality of operating modes including a recirculation mode and a onMilesce-through mode,
• wherein the recirculation mode of operation involves operating the make-up valve to maintain a sufficient water level in the sump and operating the pump to distribute evaporative liquid from the sump to the dispenser,
• wherein the once-through mode of operation involves disabling the pump and opening the make-up valve to allow evaporative liquid to be drawn from the inlet to the dispenser,
• wherein the controller is configured to monitor the level of evaporative liquid in the sump via the level sensor, and
• wherein the controller is configured to select a particular operating mode among the plurality of operating modes based at least in part the monitored level of evaporative liquid in the sump.

A method of operating a liquid dispensing system between a recirculation mode and a once-through mode, the method comprising:

• dispensing liquid over an evaporative pad with a dispenser;
• collecting run-off liquid from the evaporative pad in a sump;
• and
• monitoring parameters associated with the level of liquid within the sump;
• and
• controlling the mode of operation between a recirculation mode and a once-through mode with the controller based at least in part on the monitored parameters,
• wherein operating in the recirculation mode involves delivering liquid from the sump to the dispenser,
• wherein operating in the once-through mode involves delivering liquid from an inlet to the dispenser,
• wherein the monitoring parameters includes monitoring the level of evaporative liquid in the pump via a level sensor, and
• wherein the controlling the mode of operation includes selecting one of the recirculation mode and the once-through mode based at least in part the monitored level of evaporative liquid in the sump.