Honeywell International Inc.

Camel Zhang

Daniel J Sullivan

Levi H Geadelmann

Gary Yang

Angela Zhao

Paul C Wacker

Nicholas Dalsin

Amy L Anderson

Jeff Gao

A fan coil thermostat includes a controller that implements a control algorithm that includes an Auto fan speed mode. The controller is programmed to permit a user to manually select a fan speed setting using the user interface. In response, the controller initiates a timer, and automatically returns to the Auto fan speed mode once the timer expires.

Fan coil thermostat with automatic fan reset

Fan coil thermostats can provide energy savings by, for example, not unnecessarily heating and/or cooling an unoccupied room or other space. Fan coil systems employing such a fan coil thermostat may be more energy efficient. A fan coil system may include a fan coil that is configured for fluid communication with a source of heated fluid and/or a source of cooled fluid, a valve that controls fluid flow through the fan coil, a fan that blows air across the fan coil and a fan coil thermostat. The fan coil thermostat may include a controller that implements a control algorithm that may include an unoccupied temperature setting. The controller may be programmed to permit a user to enter a user-chosen temperature setting. In response, the controller may initiate a timer, and may automatically return to the unoccupied temperature setting once the timer has expired.

Fan coil thermostat with activity sensing

Methods and apparatus for automatically changing between heating and cooling in an HVAC system. In one example, an HVAC controller may monitor the temperature of an inside space of a building, and may switch the HVAC system to cooling when the temperature of the inside space rises above a high switch-point temperature, and may cool the inside space to at least below the high switch-point temperature. The HVAC controller may also switch the HVAC system to heating when the temperature of the inside space falls below a low switch-point temperature and may heat the inside space to at least above the low switch-point temperature. In some cases, after switching to heating or cooling, the HVAC controller may cause the HVAC system to heat or cool the inside space, respectively, to substantially the set-point temperature.

Automatic changeover control for an HVAC system

Fan coil thermostats can provide energy savings by, for example, operating a fan coil system more efficiently. Fan coil systems employing such a fan coil thermostat may be more energy efficient. A fan coil system may include a fan coil that is configured for fluid communication with a source of heated fluid and/or a source of cooled fluid, a valve that controls fluid flow through the fan coil and a fan that blows air across the fan coil. The fan coil thermostat may include a controller that implements a control algorithm that calculates an error percentage value relating to a temperature difference between the current temperature and the temperature set point. The error percentage value may include a proportional term related to the temperature difference and an integral term related to the temperature difference. The controller may regulate the fan speed in accordance with the calculated error percentage.

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Tianjin, China

Camel Zhang