Systems, apparatus and methods for operating an environmental control system that delivers dehumidified outdoor air into a conditioned space through an air valve. The method includes establishing CO.sub.2 setpoints corresponding to a ventilation outdoor air flow rate and a dehumidification outdoor air flow rate, determining a humidity metric of the conditioned space, and delivering outside air to the conditioned space at the ventilation outdoor air flow rate or dehumidification outdoor air flow rate based upon the humidity metric. The outside air may be tempered with return air from the conditioned space. The dehumidification CO.sub.2 set point is determined by predicting the dehumidification CO.sub.2 set point based on the airflow quantity per occupant and the relationship of the occupant predicted water vapor emission rate and CO.sub.2 emission rate.

Supply air conduit (7) along which air is sent from outdoors to indoors by the air supply fan (9), exhaust air conduit (8) along which air is sent from indoors to outdoors by the air exhaust fan (10), and heat exchange element (6) provided at a position where supply air conduit (7) and exhaust air conduit (8) intersect, for exchanging heat between indoor air and outdoor air for ventilation are included. In addition, in exhaust air conduit (8), humidity detection unit (14) is provided at a position upstream of heat exchange element (6), and, in supply air conduit (7), temperature detection unit (13) is provided at a position upstream of heat exchange element (6). In addition, controller (11) reduces, when a temperature detected by temperature detection unit (13) and humidity detected by humidity detection unit (14) are predetermined values, speed of an air supply motor and an air exhaust motor so that air flow rates at which moisture neither condenses nor freezes are attained.

A control device, an air conditioner, and a control method thereof are provided. The control device includes a communication interface configured to communicate with an external device, and a processor configured to control the communication interface to receive indoor and outdoor environment information and user control information, and the processor is configured to predict an indoor temperature over time through a temperature prediction model based on the received indoor and outdoor environment information and the user control information, obtain a corresponding candidate setting temperatures, obtain temperature control schedules, predict energy consumptions of the obtained temperature control schedules, respectively, through a trained energy prediction model, identify a temperature control schedule with the smallest predicted energy consumption as an optimal temperature control schedule, and transmit control information over time to an air conditioner during a pre-set power saving operation time based on the identified optimal temperature control schedule.

An air conditioner and a control method thereof are provided. The air conditioner includes a sensor portion including at least one sensor, a controller including at least one control portion to control a function of the air conditioner, and at least one processor operatively connected to the sensor and the controller. The at least one processor is configured to obtain an airflow speed and indoor environmental data by the sensor portion while the air conditioner is operating, generate a first algorithm by applying the obtained airflow speed, the indoor environmental data, and pre-stored reference data to a second algorithm, and control operation of the air conditioner based on the generated first algorithm.

Dynamically cycling of air in an indirect evaporative cooler. A heat exchanger includes a dry passage separated from a wet passage by a membrane, the dry passage including an intake portion, an outlet portion, and a loop portion. By selectively passing intake air from the intake portion and/or recirculation air from the loop portion using a mixing valve, air is moved into and through the loop portion. The air within the heat exchanger can be selectively passed outside through the outlet portion and/or recirculated by the mixing valve. In this manner air is able to be circulated a number of loop circuits through the loop portion, enabling cooling and/or dehumidifying of air.

In a ventilation control device, a ventilation-path setting unit is configured to set a ventilation path based on environmental information acquired by an information acquisition unit. A ventilation-quantity setting unit is configured to set a ventilation quantity based on the environmental information and the ventilation path. The ventilation-path setting unit sets a plurality of candidate paths having priorities in descending order of expected ventilation effects. In the case where a first candidate path having the highest priority is identical with a previously set ventilation path, the ventilation-path setting unit sets the first candidate path as the ventilation path, when a difference value between a room temperature previously acquired and a room temperature presently acquired is equal to or more than a threshold. The ventilation-path setting unit sets, as the ventilation path, a second candidate path having the second highest priority, when the difference value is less than the threshold.

A system and method for a controller of economizers operatively connected to HVAC equipment. The controller is adapted to maintain the temperature within a facility based on inside air setpoints and outside air setpoints. The controller receives inside air temperature readings and compares them to inside air setpoints in order to determine the cooling demand for the facility. The controller also receives outside air temperature readings and compares them to outside air setpoints in order to determine which economizers may be activated. The outside air setpoints may be dynamically adjusted to adapt and meet the cooling demand of the facility. The controller compares the outside air setpoints to predetermined maximum and minimum setpoints in order to determine whether to adjust the outside air setpoints.

According to certain embodiments, a thermostat is configured for use in a climate control system. The thermostat is operable to use two-way communication for communicating operational information between the thermostat and at least one rooftop unit (RTU) within the climate control system. For example, the two-way communication comprises sending first operational information to the RTU and receiving second operational information from the RTU. The operational information comprising one or more climate control commands, setpoints, configuration information, diagnostics, and/or sensor data. The thermostat is further operable to operate the climate control system based on the operational information communicated between the thermostat and the RTU.

A Variable Refrigerant Flow (VRF) dehumidification system. The system has at least one condenser module in fluid communication with one or more indoor air handlers. At least one evaporator coil is in fluid communication with the indoor air handlers and at least one reheat/reclaim coil. The evaporator and reheat/reclaim coils are also in communication with the condenser module. A plurality of electronic expansion valves (EEVs) are in fluid communication with the indoor air handlers. A plurality of sensors is disposed in the system and are in communication with at least one VRF dehumidification system controller. In one embodiment, a logic is stored in a non-transitory computer readable medium that, when executed by one or more processors, causes the VRF dehumidification system to monitor the data input from the plurality of sensors and regulates the capacity of the VRF dehumidification system needed to maintain a set dew point parameter.

An air conditioner system (1) runs in a concentration keeping mode to sequentially repeat a first operation of lowering a target temperature to a first target temperature lower than a predetermined reference temperature and a second operation of raising the target temperature to a second target temperature higher than the reference temperature. The target temperature is gradually raised from the first target temperature to the second target temperature in the second operation. Lowering the target temperature to the first target temperature in the first operation takes shorter time than raising the target temperature to the second target temperature in the second operation.