A control system can provide a linear behavior of airflow as a function of damper position of each zone damper in an HVAC system. The control system incrementally closes each zone damper from a fully open position to a fully closed position, and records static pressure measurements with each change in damper position. Then, using a mathematical model that is derived from the second fan law, a correction is calculated for each damper position of each zone damper based on the recorded static pressure measurements to provide corrected damper positions at which the airflow through the zone damper exhibits a linear behavior. The corrected damper positions are stored and used during an operational cycle of the HVAC system to obtain a precise airflow through the zone dampers.

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.

A method for calibrating a product valve disposed along a flow path in a duct, with a calibration valve in a duct remote from the product valve and having a geometric shape and operational parameters corresponding to those of the product valve. A calibration controller establishes calibration conditions and, in responsive thereto, generates a calibration flow rate (CFM) function by measuring for the calibration valve, a sparse set of flow rates and determining a surface-fit mathematical representation of fluid flow through the calibration valve over applied calibrated flow rates and the measured pressure drops. The CFM Function is transferred to a product blade controller, which in turn, processes the representation of the mathematical surface, and controls fluid flow through product valve based on values extracted from the received CFM Function as well as at least one parameter control signal indicative of a desired set point.

A network of wireless remote climate sensors in a heating, ventilation, and air conditioning (HVAC) system permits the creation of personalized microclimates within an enclosed space. In addition to collecting temperature and humidity data, the wireless remote climate sensors can detect whether the enclosed space is occupied by a human. Human detection is made possible by optional cameras, microphones, and gas sensors on the wireless remote climate sensors. As the human moves throughout the enclosed space, the HVAC system is able to track the human's movement using the wireless remote climate sensors. The HVAC system may adjust airflow to different portions of the enclosed space based on the human's location. The result is an efficient use of system resources to keep users at their ideal temperature.

A damper for a furnace, the damper including an air port damper body engaged to an air port opening of a furnace; and at least one velocity plate in hinged engagement to the air port damper body so that an air controlling end surface of the at least one velocity plate is substantially aligned to a wall of the furnace at the air port opening when the at least one velocity plate is in a fully opened position.

A Fluid Flow Control System (FFCS) door assembly includes a continuous belt and a plurality of rollers. The plurality of rollers support the continuous belt and define a first segment, a second segment, a third segment, and a fourth segment. The continuous belt includes a plurality of openings that selectively allow fluid flow to pass through the first segment, the second segment, the third segment, and the fourth segment when two openings of the plurality of openings align with the first segment, the second segment, the third segment, or the fourth segment.

A method of controlling a ceiling type air conditioner including a panel located on a ceiling surface, outlets formed at positions corresponding to four sides of the panel, a first vane group for opening and closing the outlets located at two opposing sides, and a second vane group for opening and closing the outlets located at the other two opposing sides includes performing a dynamic airflow mode in which an indoor temperature reaches a set temperature by controlling rotation angles of the first vane group and the second vane group, and calculating a pleasant airflow index Y for determining a pleasant feeling of a user at the set temperature. The pleasant airflow index is calculated using the indoor temperature, the rotation angle of the first vane group or the second vane group, an air volume, a distance from a floor surface and an airflow position as variables.

Embodiments include systems and methods for linearization of airflow through dampers of a heating, ventilation, and air conditioning systems. In one embodiment, a system may include a fan, a first damper for a first zone of the system, the first damper configured to move from a first position to a second position, and from the second position to a third position; and a controller. The controller may be configured to determine a first corrective positional adjustment for the first damper for the second position at a first time interval, and determine, using the first corrective positional adjustment, a fourth position for the first damper, wherein the first damper moves to the fourth position instead of the second position during a second time interval.

There is described a zone controller and method for identifying a root cause failure at a zone. The zone controller determines whether a temperature measurement deviates from a temperature setpoint of the temperature sensor, and generates a first repair code, a second repair code, and/or a third repair code. The first repair code replaces a temperature sensor in response to detecting that a reading of the temperature sensor has failed. The second repair code releases an operator override on the reading of the temperature sensor in response to detecting that the reading of the temperature sensor has been overridden. The third repair code releases an operator override on a setpoint of the temperature sensor in response to detecting that the setpoint of the temperature sensor is outside the predetermined setpoint range. One or more of these repair codes are provided to a remote device.

A heating, ventilation, and air conditioning (HVAC) system includes a reheat valve configured to receive a refrigerant flow and regulate division of the refrigerant flow provided to a reheat coil and a condenser. The HVAC system also includes a condenser fan configured to draw a flow of outdoor air across the condenser and a controller communicatively coupled to the reheat valve and the condenser fan. The controller is configured to monitor a position of the reheat valve and to control operation of the condenser fan based on a correspondence between the position of the reheat valve and a threshold degree of opening.