A system and a method for operating an air handling unit (AHU) at an effective static pressure setpoint in a HVAC system. The method includes receiving airflow setpoint values from each of a plurality of variable air volume (VAV) units to determine a combined airflow set point for the plurality of VAV units of an air handling unit (AHU). The method also includes determining an effective static pressure setpoint for the AHU based on a relation between the combined airflow setpoint value and a static pressure represented by a system effect curve.

Many import and export regulations require fumigation of goods, such as products or commodities, to ensure that non-native pests are not introduced. The fumigating process can involve placing the goods in a sealed containment system, and introducing the sealed good to a fumigant, such as methyl bromide gas, for a predetermined amount of time. After fumigation, regulations may require how to dispense the fumigant. The fumigant can be exhausted through fans, baffles, dampers, filters, and a chimney, as part of an emission system, in a controlled manner. The controlled manner can include combining the fumigant with ambient air and releasing or exhausting the combination over an amount of time, which mitigates pollution by the fumigant. The time-period is not specific, and instead is the time needed to meet regulatory requirements.

A solid-state sensor, including an enclosure having a first opening in a first side of the enclosure and a second opening in a second side of the enclosure, a first passageway in fluid communication with the first and second openings, and a solid-state direction sensor positioned within the first passageway. The solid-state direction sensor can include a first sensor positioned at a first axial position, a second sensor positioned at a second axial position, and a flow deflector positioned at a third axial position that is between the first and second axial positions. The flow deflector can extend into the first passageway so as to constrict the first passageway.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for monitoring an HVAC system. One of the methods includes receiving pressure data from one or more sensors monitoring a supply air duct of an HVAC system at a property that indicates a pressure in the HVAC system; determining, using the pressure data, that the pressure satisfies a pressure threshold for the HVAC system; and in response to determining that the pressure satisfies the pressure threshold, adjusting an actuator-controlled damper between the supply air duct and a return air duct or adjusting a fan speed of the HVAC system.

Systems and methods for monitoring ventilation effects in one or more locations are described herein. In various embodiments, a server computer 120 tracks CO.sub.2 level changes measured for a plurality of locations over a plurality of intervals of time over a plurality of days. When the server computer 120 receives data indicating performance of a ventilation action at a particular location and time, the system tracks changes in CO.sub.2 levels to determine whether the device is operating optimally and, if the device is not operating optimally, sends a notification to a client computing device. Using tracked CO.sub.2 level changes, the server computer 120 may identify ventilation actions to perform at different points in time and send instructions to a ventilation system which, when executed, cause performance of the ventilation actions.

Supply Air device (1) for controlling supply air flow to a building space, comprising a chamber (2) having a supply air inlet (3) and an air outlet (4). A first tube (10) in the chamber is connected at an open first end (11) to the supply air inlet, wherein the first tube has a side wall (13) which is permeable to air. A throttle member (30) is slidably connected to the first tube to change a degree of exposure of the side wall to control air flow through said side wall to the outlet. The exposable side wall comprises a layer of porous material (14) through which air is discharged.

In-situ calibration of a flow measurement device in a forced air HVAC system. A flow measurement that is obtained by a flow measurement device that is temporarily installed in the HVAC system is used to calibrate a flow measurement device that is permanently installed in the HVAC system. The calibration described herein can be aided by a technician installing or servicing the HVAC system.

A heating, ventilation, and air conditioning (HVAC) system includes a controller associated with a residence. The controller is configured to determine an expected value range for an operating parameter of a component of the HVAC system. Additionally, the controller is configured to receive a signal from a sensor indicative of a current value of the operating parameter of the component and determine if the current value of the operating parameter is outside the expected value range. Based on the determination that the current value is outside the expected value range, the controller is additionally configured to initiate a diagnostic mode of the controller. In the diagnostic mode, the controller is configured to collect diagnostic data associated with the HVAC system.

An air treatment system controls airflow volume in accordance with momentarily varying airflow volume to be demanded. A supply fan unit is disposed separately from an air treatment unit, and sends outdoor air from an outdoor space to the air treatment unit and sends outdoor air treated by the air treatment unit to an indoor space. An exhaust fan unit is disposed separately from the air treatment unit, and sends indoor air from the indoor space to the air treatment unit and sends indoor air treated by the air treatment unit to the outdoor space. A controller controls a rotation speed of a first fan in accordance with a first detection value of a first airflow volume detection unit, and controls a rotation speed of a second fan in accordance with a second detection value of a second airflow volume detection unit.

A temperature load management device is for use in exposing a user to a second environment for removing a first temperature load accumulated in a first environment. The temperature load management device includes the control unit as a main component. The control unit controls the second environment or makes a notification of a time to end the exposing of the user to the second environment, based on physiological information on the user.