A displacement ventilation system includes a vertical duct located inside an enclosed space and extending between a floor and a ceiling of the enclosed space, an air inlet coupled with the vertical duct for drawing air into the displacement ventilation system, and an elongated diffuser extending adjacent the floor for diffusing at least some of the outside air over the floor of the enclosed spaced. The displacement ventilation system desirably includes a return air duct extending adjacent the ceiling and being coupled with the vertical duct for removing return air from the enclosed space and advancing the return air toward the vertical duct, a heat exchanger for transferring thermal energy between the return air and the outside air, and a heat pump for changing a temperature level of the outside air or the return air passing through the heat pump.

A system having a mixed air box with inputs of return air from a space or spaces of a building, and of outside air. The mixed air box may have an output of discharge air to the space or spaces of the building. The air from the output may be return air that is conditioned with cooling, heat, or outside air. A damper may be situated at the input of outside air to the mixed air box. A temperature sensor may be positioned at the input for outside air and at the output of discharge air. A cooling mechanism may be at the output of the discharge air. The temperature sensor may be downstream from the cooling mechanism. An economizer may have connections with the damper, the temperature sensor and the cooling mechanism.

A disclosed air conditioning control system includes: a flow path through which cooling air discharged from an exhaust surface of an electronic apparatus is returned to an intake surface thereof, a damper provided in the flow path, a temperature measuring unit for measuring the real temperature of the cooling air, a humidity measuring unit for measuring the real humidity of the cooling air, a target value changing unit for changing target temperature and humidity in accordance with the real temperature and humidity, and a controlling unit for predicting future predicted values of the real temperature and humidity, and controlling the opening extent of the damper such that the predicted temperature and humidity become close to the target temperature and humidity, respectively. The target value changing unit sets the target temperature and humidity such that the real temperature and humidity are raised and lowered in the opposite directions.

A multifunction adaptive whole house fan system can include a whole house fan to pull large volume of air through a building structure. The whole house fan can pull air from a motorized window or damper into the building structure and expel air through an attic. The system can monitor the environment to operate the whole house fan when desired conditions are present in coordination with other systems of the building structure to reduce overall energy consumption.

A method of minimizing compressor use in an HVAC system for an IT space includes configuring an HVAC system to cool an IT space, providing a control system to operate the HVAC system, the control system having software configured to calculate economization mode minimum achievable X-Factor for a predetermined period of time, providing at least one parameter to the control system, the at least one parameter including X-Factor history and period weather forecast(s), setting temperature set points for each forecast interval, and analyzing the temperature set points according to maximum and minimum temperature parameters for the IT space, with intervals with set points violating the maximum temperature parameter being designated as intervals for which the compressor will operate while intervals with set points violating the minimum temperature parameter are assigned the minimum temperature set point.

An air channeling sub-system may include a mechanical cooling section and a direct evaporative cooling section. The direct evaporative cooling section may be downstream from the mechanical cooling section. Cooling air is channeled through the air channeling sub-system and into the room. If a first set of control conditions is met, the air channeling sub-systems is operated in an adiabatic mode. The adiabatic mode includes channeling cooling air through the direct evaporative cooling section to evaporate water into the cooling air. If a second set of control conditions is met, the air channeling sub-system is operated in a hybrid mode. The hybrid mode includes channeling cooling air through the mechanical cooling section to remove heat from the cooling air and channeling the cooling air through the direct evaporative cooling section to evaporate water into the cooling air.

Apparatus and method for heating/cooling buildings and other facilities. An elongate pipe filled with water or other fluid medium forms a thermal gradient header having temperature zones that are progressively warmer towards one end and cooler towards the other. Multiple heating/cooling systems are connected to the header so as to draw fluid from zones that are closest in temperature to the optimal intake temperature of each system, and to discharge fluid back to the header at zones that are closest to the temperature to the optimal output temperature of each system, allowing each heating/cooling system to take advantage of the thermal output of other systems. The pipe forming the thermal gradient header may be routed back and forth in the facility to define a series of legs containing the different temperature zones. A boiler or other source may supply makeup heat to the thermal gradient header, and excess heat may be sent from the header to a ground field or other thermal reservoir for later use.

An environmental control system for a building in a geographic location and having a heating, ventilation and air-conditioning (HVAC) system includes at least one computer-readable medium having instructions stored thereon that, when executed by at least one processing device in communication with the external application, enables the at least one processing device to receive weather data characterizing a weather forecast over a predetermined time period for the geographic location, receive free-cooling window data, determine, based on the weather data and free-cooling window data, an available free-cooling time window, and issue to the external application an executable command to the HVAC system to enter free-cooling mode during the available free-cooling time window.

A system and method for advanced digital economization for an HVAC system having an economizer. A digital processing unit is configured to open a damper of an economizer within a dead-band range that allows for preemptive cooling prior to a call for cooling. This economization strategy allows for free cooling (outside air) without having to pay energy costs for cooled (air-conditioned) air. The system and method can be used with or without demand control ventilation (DCV). The method also includes a “self-learning” strategy with outside air and return air sensor to regularly sense past economizer damper modifications and average out recent readings to help set the dead-band range. The method can include the ability to work in conjunction with a variable supply fan speed control, provide fault detection, self-correct, auto-configure, and report system status.

There are disclosed controllers and methods for managing economizer outputs. The economizer controller comprises an input component, a processor, and an output component. The input component receives incoming control signals from an input device, in which each incoming control signal is associated with a corresponding compressor. The processor generates an altered association of some of the incoming control signals to a different compressor based on a predetermined criteria. The output component sends output control signals based on the altered association to a control circuit associated with the compressors.