A motor control system for heating, ventilation, and air conditioning (HVAC) applications is described. The motor control system includes a thermostat and an electronically commutated motor (ECM) coupled to the thermostat. The ECM is configured to retrofit an existing non-ECM electric motor included in an HVAC application and to operate in one of a plurality of HVAC modes. The HVAC modes include at least one of a heating mode, a cooling mode, and a continuous fan mode. The HVAC mode is determined based at least partially on outputs provided by the thermostat.

Embodiments of the invention provide an air conditioning unit and a ventilator. The ventilator has an impeller to draw outside air into an enclosure and cause air within the enclosure to be exhausted to the outside. The ventilator can be tied into the air conditioning unit's control system and act to supplement the cooling and ventilation needs of the space. Alternatively, the ventilator can have a separate integral control system. By having a separate control system, the ventilator can operate as a stand-alone device.

An air circulation and ventilation system for an enclosure. The system includes a fan assembly subsystem with a housing defining a manifold. The housing has a first intake aperture configured to receive air from within the enclosure, a first outlet aperture configured to emit air from the manifold to outside the enclosure, and a fan configured to draw air in through the first intake aperture. The system includes a pressure equalization subsystem having a port configured to allow additional air into the enclosure. The port includes a damper for selectively opening and closing the port. The system also includes a switching subsystem with a switch operably coupled to the fan and the damper. The switch selects between a first mode where the damper is closed and the fan is off and a second mode where the port damper is open and the fan is on.

A controller is provided for HVAC equipment. The controller receives a set of internal temperature values, and a set of external temperature values, the set of external temperature values representing at least one non-current temperature. The controller determines a predictive internal temperature value from the set of internal temperature values and a predictive external temperature value from the set of external temperature values. The controller receives an internal humidity value representing humidity within the premise, the controller further controls the HVAC equipment to modify the humidity within the premise when the received internal humidity value is different from a humidity set point; and the humidity set point is regulated by a humidity limit value, the humidity limit value being where condensation forms, the humidity limit value being calculated using the predictive internal temperature value and the predictive external temperature value.

A zoned HVAC system comprises an HVAC unit including a climate control system and an air mover. In addition, the system comprises a supply air duct in fluid communication with the outlet of the HVAC unit. Further, the system comprises a return air duct in fluid communication with the inlet of the HVAC unit. Still further, the system comprises a plurality of zones positioned between the supply air duct and the return air duct. Moreover, the system comprises a bypass duct extending between the supply air duct and the return air duct. The bypass duct includes an active bypass damper having an open position, a closed position, and a plurality of partially opened positions. The system also comprises a control device configured to control the position of the bypass duct.

A fan system for a variable air volume heating and/or air conditioning unit comprising a fan array with a control system to eliminate surge at low operating flows and to maximize operating range. The fan control system includes a fan pressure sensor for determining the pressure rise across the fan array and a fan airflow sensor for determining the total airflow generated by the fan array. A surge controller is programmed to constantly monitor the calculated surge pressure as the fan speed control is modulating the fan speed in response to user demands. As airflow increases or decreases in response to changes in fan speed, so will the calculated surge pressure. The surge control turn fans on and off to ensure that the operating fans are running in their optimum fan speed ranges. Thus, the fans in the fan array are prevented from reaching the surge point.

A total heat exchanger exchanges heat between air flowing through an air supply passage and air flowing through an air exhaust passage. An air supply fan transfers air from the outside of a room into the room through the air supply passage. If the temperature of outdoor air (OA) is below a lower temperature threshold (Tth), a controller intermittently stops the air supply fan in response to an index of the moisture content in room air (RA) such that as the stage of the index of the moisture content depending on the moisture content in the room air (RA) shifts toward higher stages, the period of time during which the air supply fan is at rest in an intermittent operating cycle increases.

The object of this invention a regulation method for regulating an air conditioning system suitable for independently regulating the temperature of a plurality of zones. The air conditioning system comprises a thermal cycle machine. According to various embodiments, the thermal cycle machine is capable of delivering a cold airflow, a hot airflow or both. This flow is divided into smaller flows supplied to each of the zones to be regulated. The method according to the invention allows regulating these smaller flows as well as the operating conditions of the thermal cycle machine. According to various embodiments, the method additionally incorporates more complex variants involving variables such as pressure or thermal inertia. Likewise, according to one embodiment the air conditioning system incorporates a particular distributor configuration simplifying the installation of said regulation system.

A motor control system for heating, ventilation, and air conditioning (HVAC) applications is described. The motor control system includes a thermostat and an electronically commutated motor (ECM) coupled to the thermostat. The ECM is configured to retrofit an existing non-ECM electric motor included in an HVAC application and to operate in one of a plurality of HVAC modes. The HVAC modes include at least one of a heating mode, a cooling mode, and a continuous fan mode. The HVAC mode is determined based at least partially on outputs provided by the thermostat.

An engine cooling system includes a liquid-to-air heat exchanger having an associated fan and a pump forcing convection and a controller communicating with the fan and the pump, the controller increasing fan speed in response to a first gradient in heat transfer rate to power exceeding a second gradient in heat transfer rate to power for increasing pump speed, and increasing pump speed when the second gradient is greater than the first gradient. The controller may increase the pump speed in response to a desired increase in heat transfer rate. The first gradient may be based on a gradient in heat transfer rate to air flow from a map of heat exchanger performance. The second gradient may be based on a gradient in heat transfer rate to coolant from a map of heat exchanger performance.