A method for HVAC workload and cost logic is described. In one embodiment, the method includes detecting a thermostat of an HVAC system being set to a target temperature and upon detecting the thermostat being set to the target temperature, detecting a current indoor condition and a current outdoor condition. In some embodiments, the method includes calculating an estimated runtime of an HVAC heating or cooling cycle for the target temperature. The estimated runtime is based on the target temperature, the current indoor and outdoor conditions, and on a result of querying a correlation database. The correlation database includes data points for a plurality of previous HVAC heating and cooling cycles.

An air pressure measuring ventilation system, comprising: at least one duct; at least one motorized exhaust fan; one or more ultrasonic sensors; one or more infrared spark detectors; and one or more air pressure sensors. The at least one motorized exhaust fan may draw air through the at least one duct. The one or more air pressure sensors may be placed on a side of the at least one duct such that an air pressure is measured as the air is drawn through the at least one duct, such that a plurality of air pressure measurements are generated. The one or more air pressure sensors may be substantially flush with an interior side of the at least one duct and do not obstruct the air as the air is drawn through the at least one duct.

An air pressure measuring ventilation system, comprising: at least one duct; at least one motorized exhaust fan; one or more ultrasonic sensors; one or more infrared spark detectors; and one or more air pressure sensors. The at least one motorized exhaust fan may draw air through the at least one duct. The one or more air pressure sensors may be placed on a side of the at least one duct such that an air pressure is measured as the air is drawn through the at least one duct, such that a plurality of air pressure measurements are generated. The one or more air pressure sensors may be substantially flush with an interior side of the at least one duct and do not obstruct the air as the air is drawn through the at least one duct.

An arrangement of multiple environmental control systems for a multi-unit structure has a first environmental control system installed in a first unit, a second environmental control system installed in a second unit, a system monitor in communication with each of the environmental control systems and a firewall. Each environmental control system has a control unit coupled to the system monitor through the firewall that prevents unauthorized devices from accessing the respective control unit and a HVAC system device coupled to the respective control unit through the firewall. For each unit, a local user device that is located inside the unit is coupled to the control unit through a local communication interface, and an external user device that is located outside the unit communicates with the control unit through the firewall.

An arrangement of multiple environmental control systems for a multi-unit structure has a first environmental control system installed in a first unit, a second environmental control system installed in a second unit, a system monitor in communication with each of the environmental control systems and a firewall. Each environmental control system has a control unit coupled to the system monitor through the firewall that prevents unauthorized devices from accessing the respective control unit and a HVAC system device coupled to the respective control unit through the firewall. For each unit, a local user device that is located inside the unit is coupled to the control unit through a local communication interface, and an external user device that is located outside the unit communicates with the control unit through the firewall.

An operation management apparatus includes: a refrigerant return temperature prediction unit that predicts a temperature Tr of a refrigerant returning from an air conditioner to a heat source system; a heat storage capacity estimation unit that estimates a heat storage capacity of the heat source system, based on the predicted refrigerant return temperature Tr; and an operation plan unit that creates a plan based on the estimated heat storage capacity. The heat source system includes: a storage tank that supplies the refrigerant to the air conditioner; a refrigerant generation unit that cools the refrigerant returning from the air conditioner via the storage tank, and supplies it to the storage tank; a refrigerant feed temperature detection unit that measures a temperature of the refrigerant from the refrigerant generation unit; and a refrigerant return temperature detection unit that measures a temperature of the refrigerant returning from the storage tank.

An air conditioner includes an indoor unit installed on an indoor side, an outdoor unit installed on an outdoor side, a human detector that detects a person in a room, and a remote controller that performs radio communication with the indoor unit, and the air conditioner conditions the indoor air. The indoor unit includes an indoor unit control section that controls the indoor unit, a diagnostic section that diagnoses whether an operating state of the human detector is normal or abnormal, and a communication section that performs radio communication with the remote controller. The human detector includes a plurality of infrared sensors, a rotary table that supports each of the infrared sensors, and a human detector control section that controls the human detector. The diagnostic section diagnoses whether the operating state of the human detector is normal or abnormal by comparing the detected results between the respective infrared sensors on receiving a trigger signal transmitted from the remote controller.

A thermostat may include one or more memory devices comprising a stored setpoint schedule, one or more temperature sensors configured to provide temperature sensor measurements, and a processing system configured to be in operative communication the one or more memory devices to determine a setpoint temperature, and in still further operative communication with a heating, ventilation, and air conditioning (HVAC) system to control the HVAC system based at least in part on the setpoint temperature and the temperature sensor measurements. The processing system may be configured to control the HVAC system by receiving an indication that a total instantaneous energy usage rate for a structure in which the thermostat is installed is projected to exceed a threshold amount; and altering the stored setpoint schedule to reduce an energy usage rate of the HVAC system.

An apparatus and method for providing selective fan or vent cooling are disclosed. An example embodiment includes: a return plenum box having a return box opening, a fan opening, and a return duct opening; a fan coupled to the fan opening; a controller coupled to the plenum box; and an adjustable damper coupled to a hinge point of the return plenum box, the damper being adjustable between a closed position, which blocks the fan opening and an open position that blocks the return duct opening.

An air-conditioning device includes a plurality of duct modules and a power module. The duct modules each have a temperature-adjusting unit, an air flow-guiding unit and an energy transmission module. The temperature-adjusting unit is disposed at the second end of the duct module, and has opposing first and second side surfaces. The air flow-guiding unit is disposed at the duct module. The energy transmission module is disposed between the temperature-adjusting unit and the air flow-guiding unit. The power module provides operational power for the duct modules. The air flow-guiding unit guides air flow to enter from the first end of the duct modules. The energy transmission strength of the air flow is enhanced from the energy transmission module. The air flow passes through the first or second side surface of the temperature-adjusting unit, and exists from the second end of the duct modules.