Abstract: A gas-fired atmospheric pressure steam humidifier having high efficiency and ultra-low NOx(3) emissions is disclosed. In some examples, the gas-fired humidifier can have an efficiency of greater than 90 percent and a NOx(3) output of less than 20 parts per million (ppm). In one aspect, the humidifier includes a secondary heat exchanger having a first heat exchange section for pre-heating combustion air and a separate second heat exchange section for pre-heating make-up water, wherein the first and second heat exchange sections are in heat transfer communication with exhaust gases generated by the gas-fired burner and combustion blower assembly. In some examples, the first heat exchange section includes orifices for enabling flue gas recirculation.

Abstract: A gas-fired atmospheric pressure steam humidifier having high efficiency and ultra-low NOx(3) emissions is disclosed. In some examples, the gas-fired humidifier can have an efficiency of greater than 90 percent and a NOx(3) output of less than 20 parts per million (ppm). In one aspect, the humidifier includes a secondary heat exchanger having a first heat exchange section for pre-heating combustion air and a separate second heat exchange section for pre-heating make-up water, wherein the first and second heat exchange sections are in heat transfer communication with exhaust gases generated by the gas-fired burner and combustion blower assembly. In some examples, the first heat exchange section includes orifices for enabling flue gas recirculation.

Abstract: A gas-fired atmospheric pressure steam humidifier having high efficiency and ultra-low NOx(3) emissions is disclosed. In some examples, the gas-fired humidifier can have an efficiency of greater than 90 percent and a NOx(3) output of less than 20 parts per million (ppm). In one aspect, the humidifier includes a secondary heat exchanger having a first heat exchange section for pre-heating combustion air and a separate second heat exchange section for pre-heating make-up water, wherein the first and second heat exchange sections are in heat transfer communication with exhaust gases generated by the gas-fired burner and combustion blower assembly. In some examples, the first heat exchange section includes orifices for enabling flue gas recirculation.

Abstract: A gas-fired atmospheric pressure steam humidifier having high efficiency and ultra-low NOx(3) emissions is disclosed. In some examples, the gas-fired humidifier can have an efficiency of greater than 90 percent and a NOx(3) output of less than 20 parts per million (ppm). In one aspect, the humidifier includes a secondary heat exchanger having a first heat exchange section for pre-heating combustion air and a separate second heat exchange section for pre-heating make-up water, wherein the first and second heat exchange sections are in heat transfer communication with exhaust gases generated by the gas-fired burner and combustion blower assembly. In some examples, the first heat exchange section includes orifices for enabling flue gas recirculation.

Abstract: A staged dry out process and control system for an evaporative media cooling system having a plurality of media stages that are selectively activated and deactivated by a control system is disclosed. The staged dry out process ensures that wet media stages are appropriately dried with minimal disruption to the staging strategy implemented by the control system. In one aspect, the staged dry out process monitors deactivated media stages to determine if the media stages reach a dry state before being activated. In another aspect, the staged dry out process locks out a media stage that has been in a wet state beyond a predetermined maximum time limit until the media stage attains a dry state. With this strategy the cooling system can operate without being required to completely shut down for a drying process.

Abstract: A cycles of concentration (COC) control process and system for an evaporative media cooling system having a water storage tank in fluid communication with a drain valve and a refill valve is disclosed. In one step, the COC control process includes the step of executing a plurality of discrete refill events to maintain a level or volume of water within the storage tank. In another step, the COC control process includes the step of executing a discrete drain event, equaling the volume of a refill event, after a discrete refill event has been executed when necessary to maintain a target cycles of concentration value of the water within the storage tank. In one embodiment, a discrete drain event is executed when the number of refill events is greater than or equals a target cycles of concentration of the water in the storage tank.

Abstract: A staging control process for an evaporative media cooling system having a plurality of media stages is disclosed. In one step, a leaving air dry bulb temperature setpoint for air exiting the evaporative media cooling system is received or defined. In one aspect, an expected media exit dry bulb temperature is calculated for each media stage based on a dry bulb temperature and a wet bulb temperature of air entering the media cooling system and based on a measured or assigned condition of the media. In another aspect, an estimated combined leaving dry bulb temperature is calculated for different combinations of activated and deactivated media stages. Once the estimated leaving temperature is known, the method can then activate the media stage(s) associated with the combination that has an estimated combined leaving dry bulb temperature that is nearest to but less than the leaving air dry bulb temperature setpoint.

Abstract: An evaporative media system having multiple media stages each served by a separate pump is disclosed. In one aspect, the evaporative media system has a first media stage and a second media stage. A first pump is provided that is configured to deliver water from the first compartment of the water storage tank to the first media stage. Additionally, a second pump is provided that is configured to deliver water from the first compartment of the water storage tank to the second media stage. Additional media stages and pumps may be provided as well. The disclosed configuration eliminates the need for individual staging valves, provides a higher level of operational redundancy, reduces electrical consumption, and can be provided at a lower cost, as compared to many existing systems.

Abstract: A cycles of concentration (COC) control process and system for an evaporative media cooling system having a water storage tank in fluid communication with a drain valve and a refill valve is disclosed. In one step, the COC control process includes the step of executing a plurality of discrete refill events to maintain a level or volume of water within the storage tank. In another step, the COC control process includes the step of executing a discrete drain event, equaling the volume of a refill event, after a discrete refill event has been executed when necessary to maintain a target cycles of concentration value of the water within the storage tank. In one embodiment, a discrete drain event is executed when the number of refill events is greater than or equals a target cycles of concentration of the water in the storage tank.

Abstract: An evaporative media system having multiple media stages each served by a separate pump is disclosed. In one aspect, the evaporative media system has a first media stage and a second media stage. A first pump is provided that is configured to deliver water from the first compartment of the water storage tank to the first media stage. Additionally, a second pump is provided that is configured to deliver water from the first compartment of the water storage tank to the second media stage. Additional media stages and pumps may be provided as well. The disclosed configuration eliminates the need for individual staging valves, provides a higher level of operational redundancy, reduces electrical consumption, and can be provided at a lower cost, as compared to many existing systems.

Abstract: A staged dry out process and control system for an evaporative media cooling system having a plurality of media stages that are selectively activated and deactivated by a control system is disclosed. The staged dry out process ensures that wet media stages are appropriately dried with minimal disruption to the staging strategy implemented by the control system. In one aspect, the staged dry out process monitors deactivated media stages to determine if the media stages reach a dry state before being activated. In another aspect, the staged dry out process locks out a media stage that has been in a wet state beyond a predetermined maximum time limit until the media stage attains a dry state. With this strategy the cooling system can operate without being required to completely shut down for a drying process.

Abstract: A staging control process for an evaporative media cooling system having a plurality of media stages is disclosed. In one step, a leaving air dry bulb temperature setpoint for air exiting the evaporative media cooling system is received or defined. In one aspect, an expected media exit dry bulb temperature is calculated for each media stage based on a dry bulb temperature and a wet bulb temperature of air entering the media cooling system and based on a measured or assigned condition of the media. In another aspect, an estimated combined leaving dry bulb temperature is calculated for different combinations of activated and deactivated media stages. Once the estimated leaving temperature is known, the method can then activate the media stage(s) associated with the combination that has an estimated combined leaving dry bulb temperature that is nearest to but less than the leaving air dry bulb temperature setpoint.

Abstract: An evaporative cooler circulation and drain system including a fluid pump and a storage tank defining an interior volume for holding a fluid is disclosed. In one aspect, the system is operable between a circulation and drain-circulation operational modes. In the circulation mode, a drain valve is closed and the fluid pump is activated such that fluid is continuously circulated within the storage tank to discourage debris from settling by keeping debris in the tank in suspension. In the drain-circulation mode, the drain valve is opened and the fluid pump is activated such that fluid is both being continuously circulated within the interior volume of the storage tank and draining from the tank. In some embodiments, the system increases the drain flow rate by directing circulated fluid directly at a drain opening of the tank to flush debris through the drain piping and prevent plugging.