Abstract: An adjustable height housing enables a thermostatic mixing valve (TMV) with a dial permitting manual control of bathtub shower water temperature to be vertically mounted in a horizontal bathtub deck. The housing can be installed on a narrow bathtub rim yet also accommodates substantial substrate thickness of bathtub decks where required. Manual adjustment of hot and cold ring stops is performed from the top-side using only a screwdriver to gain access. The housing includes a long threaded outer sleeve which extends from near the top deck surface to the thermostatic mixing valve (TMV) cartridge body housing below, thereby accommodating any deck thickness from a 1/16 inch thick stainless steel tub edge to a compound deck construction up to 2¾ inches thick. The rotatable temperature dial is coupled to a cap rotatable by the adjustment handle which, in turn, rotates an adjustable extension shaft within the housing.

Abstract: A thermostat is provided that is capable of reliably reducing the operation of an air conditioner and other systems to provide energy cost savings to the consumer and load reduction to a utility provider. The thermostat includes at least one sensor configured to communicate information indicative of the temperature within the space, and a memory for storing at least one temperature offset value associated with a request for reduced heating or reduced cooling operation. The thermostat further includes a controller in communication with the at least one sensor, which is configured to periodically determine a temperature value for the space and to control heating or cooling of the space until the determined temperature value has substantially reached the set-point temperature.

Abstract: A thermostat is provided that includes a peripheral edge that, at least in part, defines an opening in the thermostat. The thermostat further includes a carbon monoxide sensor capable of sensing the presence of carbon monoxide gas in the ambient air near the thermostat, and providing a measurable output value that is indicative of the level of carbon monoxide gas. The thermostat also includes a replaceable battery that applies a voltage to the carbon monoxide sensor. The thermostat further includes a microprocessor disposed on a circuit board. The circuit board, sensor and battery are together disposed on or in the thermostat. The circuit board is configured to establish an electrical connection with the carbon monoxide sensor and the battery. The microprocessor is configured to periodically read the carbon monoxide sensor output, and to activate an audible alarm in a continuous manner to indicate an emergency upon detecting a carbon monoxide level that exceeds a predetermined value.

Abstract: A method for monitoring a condenser in a refrigeration system includes calculating a thermal efficiency of the condenser based on operation of the condenser and averaging the thermal efficiency over a predetermined period. Further, the method comprises comparing the average to an efficiency threshold and generating a notification based on the comparison. The method may be executed by a controller or stored in a computer-readable medium.

Abstract: The invention relates to a thermostat including a user interface module. The user interface module has a display, a plurality of user interface buttons, and a first power and communications interface. The thermostat also includes an I/O module, the I/O module electrically coupled to a HVAC plant and the I/O module having a plurality of switches to control the HVAC plant, and a second power and communications interface. The user interface module and the I/O module are communicatively coupled and exchange power via the power and communications interfaces and the thermostat can be mounted and operated in one of two user selectable installations: a stacked configuration comprising a thermostat having the user interface module directly mounted to the I/O module, or a remote configuration comprising a thermostat having the user interface module remotely mounted from the I/O module.

Abstract: Systems and methods for monitoring, controlling and limiting utility usage for a plurality of units in a building. An example system includes a controller and one or more sensing devices in signal communication with the controller using a buildings existing thermostat wiring. The system senses the state of a thermostat, the air temperature near each thermostat and the pipe/ducting temperature in each of a plurality of units. The pipe/ducting sensor monitors the temperature of piping or ducting leading from a thermostatically controlled supply valve to the unit requesting heating or cooling. Being able to use existing building thermostat wiring allows for installation into older buildings. The controller records utility usage information for each of the plurality of units based on information received from the one or more sensing devices and communicates with a website.

Abstract: The present invention provides a thermostat with GFCI which includes control module, keyboard module, communication module and display module, and it further includes a leakage detection module, and the control module includes the temperature sensor, and the leakage detection module is connected with the control module, keyboard module and display module respectively. The control module is connected with the controlled device by the leakage detection module. The thermostat monitors current status of output circuit while adjusting the temperature of room, so that it can ensure the safety of the output circuit in use. If leakage occurs to the controlled device, the thermostat can cut off the power and stop power supplying at once, and the alarm light illuminates in the meantime. After manual reset, the alarm light goes out.

Abstract: An HVAC controller may include an upper housing having a front and a back, the back including a center. A lens dial including an engagement portion may be rotatably secured relative to the upper housing. A set point operator may include a first portion that is disposed about the upper housing center as well as a second portion that is adapted to interact with the lens dial engagement portion. A mechanical movement to electrical signal converter such as a potentiometer may be disposed within the HVAC controller such that the first portion of the set point operator communicates with the potentiometer.

Abstract: An electronic thermostat is disclosed comprising a connector (6) provided with means (7) for sealing an outer body (1) provided with a cavity (60) within which there is housed a circuit card (2); the thermostat comprises a temperature sensor (103) exposed to ambient temperature under control and connected to the circuit card. The temperature sensor is a semiconductor sensor and is housed inside a cavity (101) of a flange (100) removably fixed to the body (1). The circuit card (2) is provided with a memory and the thermostat comprises setting means (4) housed inside the cavity of the outer body and comprising at least one button (12-13), said connector (6) being connected to the lateral surface of the outer body (1) and said cavity (60) of the outer body communicating through an opening (73) placed at the head of said body (1) and normally covered by a removable cover (74) to enable the operator to reach said setting means (4).

Abstract: A control unit including a switch for regulating the temperature of a passenger compartment and/or the temperature of a vehicle seat. The switch is of a unit type with a control member, a switch member, a light-emitting member, and an indicator member housed in a single case, and can be disposed anywhere near a driver.

Abstract: A thermostat for controlling a climate control system is provided that comprises a network interface for establishing an internet connection with a website of a remote service provider, and a microprocessor for controlling the operation of a climate control system. The microprocessor is in communication with the network interface for establishing an internet connection and receiving user-specified information from a remote service provider that maintains a user-profile of information requested by the user. The thermostat further comprises a display device responsive to the microprocessor for displaying user-specified information received via the network controller from the remote service provider.

Abstract: A system and a method for monitoring and inspecting food safety is disclosed. The system adopts insert and use concept that only requires an initial push on a button to begin its function. The system provides visual alert for different conditions if food products are in unsafe status. The system is pre-calibrated during manufacture without complicated or multi-step calibration or recalibration procedures during application. The system relies on modern surface-mount microprocessor technology that enables long-term calibration stability along with very low power consumption for extended battery life.

Abstract: A building controller configured to display a service reminder that reminds a user to service one or more HVAC components of an HVAC system. In some cases, the building controller includes a control module configured to determine when to display the service reminder based, at least in part, on a geographical region of the building controller and seasonal data for the geographical region. The control module may display the service reminder before an HVAC component of the HVAC system is expected to switch from being dormant during a first part of the year to being active during a second part of the year.

Abstract: According to one embodiment, a first capacitive element may be provided and associated with a surface where a fouling layer is to be detected. A second capacitive element may also be provided, and a capacitance between the first and second capacitive elements may be used to detect formation of the fouling layer. According to another embodiment, a thermal device is provided proximate to a surface where a fouling layer is to be detected. A detector (e.g., a thermometer or vibration detector) may detect a condition associated with the surface, and formation of the fouling layer may be determined based at least in part on the condition.

Abstract: A system for monitoring and managing a refrigeration system of a remote location includes a management center in communication with a refrigeration system through a communication network. The management center receives performance information of the refrigeration system. The management center employs software modules to analyze the performance information; diagnose system conditions; provide alarms for food safety issues, food quality issues and refrigeration system component failure; indicate maintenance conditions; and configure the refrigeration system.

Abstract: A system is provided for use in a multi-unit building by which an occupant of a unit of the multi-unit building controls an appliance associated with the unit and includes an actuator which is accessible to the occupant, a processing unit to control the appliance, operative in the first mode, based on occupant instructions, to change the mode of the appliance based on an actuation of the actuator and to control the appliance, operative in the second mode, according to a preselected schedule, and a networking unit to inform, via communications, a monitor of the multi-unit building as to when the appliance operates in the second mode.

Abstract: A thermostat system having dedicated informational regions in a display and associated buttons or softkeys for sequential operation. The system may maximize utilization of a sectioned display and buttons for system navigation. The informational, selection and/or action design takes into consideration operational button groupings for straightforward comfort settings as well as editing of the clock, day-of-week, schedules, and so forth. Sections, regions or areas of the display may indicate immediate button operations. The changeable information in the regions associated with the softkeys or buttons may provide sequential operation of the thermostat system. The system may have multiple schedules and setpoints for heating and cooling comfort setting flexibility. A combining of individual schedules may be automatically selected. Also, there may be a system switch mode, for example, between heat and cool, where the schedules may be individually edited.

Abstract: A visual display system for use with a digital thermostat is provided. The visual display system provides an adjustable display resolution for the temperature readout provided thereon. This adjustable display resolution may be changed as desired by a user via a resolution adjustment menu. The display resolution may be adjusted to display the temperature information in tenths of degrees, half degrees, whole degrees, etc. as desired by a user. Such a display system accommodates different display resolution requirements of different original equipment manufacturer (OEM) customers who may desire different displayed resolutions without having to manufacture and stock different models.

Abstract: A thermostat that can display information in multiple different orientations is provided. The thermostat includes a housing, a display, and an input device. As the housing is mounted in a particular orientation, the thermostat changes the orientation of the information for properly displaying same to a user. This is accomplished by sensing the orientation of the housing in one embodiment, and through user selection of a desired orientation in another embodiment. A separate display and input device(s) are provided in one embodiment, and a combined touch screen display and input device is provided in another embodiment.

Abstract: A controller equipped with a user interface having multiple-day programming capabilities, including methods of programming such devices, are disclosed. The user interface may include one or more menus or screens that can be used to program a schedule for one or more selected days during the week. An illustrative method of programming the controller may include the steps of entering a scheduling routine, selecting multiple days for schedule modification, changing the schedule parameters for one or more periods during the selected days, and then exiting the scheduling routine.

Abstract: A thermostat system having dedicated informational regions in a display and associated buttons or softkeys for sequential operation. The system may maximize utilization of a sectioned display and buttons for system navigation. The informational, selection and/or action design takes into consideration operational button groupings for straightforward comfort settings as well as editing of the clock, day-of-week, schedules, and so forth. Sections, regions or areas of the display may indicate immediate button operations. The changeable information in the regions associated with the softkeys or buttons may provide sequential operation of the thermostat system. The system may have multiple schedules and setpoints for heating and cooling comfort setting flexibility. A combining of individual schedules may be automatically selected. Also, there may be a system switch mode, for example, between heat and cool, where the schedules may be individually edited.

Abstract: An HVAC controller with a simplified and/or lower cost user interface. In one illustrative embodiment, the HVAC controller includes two switches, a movable member, and a plurality of detents. The detents are configured to cause the two switches to be switched in a sequence when the movable member is moved. In some cases, a controller is coupled to the two switches, and may change an HVAC control parameter based on the switch sequence.

Abstract: A temperature indicating apparatus for indicating when temperature of a heat source exceeds a predetermined temperature includes an I/O controller, an A/D converter, a single chip microcomputer (SCM), and an indicating unit. The I/O controller outputs a temperature signal of the heat source. The A/D converter receives the temperature signal, and outputs a digital temperature signal. The SCM storing at least one predetermined temperature value, receives the digital temperature signal and converts the digital temperature signal to a temperature value, and outputs a control signal when the temperature value of the digital temperature signal exceeds the predetermined temperature value. The indicating unit includes at least one indicating lamp coupled to the SCM, the indicating lamp emits light when it receives the control signal from the SCM.

Abstract: A programmable thermostat can be programmed and configured using a set up selector keys or pushbuttons to enter set up modes and to move from screen to screen on the thermostat display, and using up and down selector keys to change the time and temperature settings within each screen or mode. The thermostat can be set into a master mode be depressing two of the selector keys simultaneously, and then the programmed settings of the thermostat can be electronically transferred to each of a batch of similar thermostats using a thermostat conductor in a multi-conductor thermostat wire such as the fan conductor. The thermostat can be toggled back to a normal or target mode for thermostat operation.

Abstract: A control assembly for a compact refrigeration unit and the like includes a display panel, a control board having an LED and a switch pad, a flexible extension extending between the switch and the display panel, and a mount supporting the display panel and control board and having a switch support laterally restraining the flexible extension and an open ended light guide directing light from the LED to the display panel. The mount can be a monolithic structure having a switch support and light guide for each of multiple switches and LEDs. The mount includes a removable back cover that clamps the control board in place.

Abstract: A thermostat is provided that comprises a touch-sensitive transparent membrane adapted to be affixed over a display, where the transparent membrane has a plurality of membrane switches. The thermostat comprises a microprocessor in communication with the plurality of membrane switches, and has a memory for storing a program for controlling the operation of the climate control system. The thermostat further comprises a display device responsive to the microprocessor for displaying a first screen having at least a first user-interface icon associated with at least one membrane switch, where in response to the user touching the membrane switch associated with the first user-interface icon the display device displays a second screen having at least a run user-interface icon and a schedule user-interface icon.

Abstract: An air conditioning control device is configured to obtain and control data on an air conditioner, which includes a plurality of indoor units. The air conditioning control device includes a data retrieval component, a data collection component, an analysis component, and an analyzed results display component. The data retrieval component retrieves air conditioner operating data including power consumption data for each indoor unit. The data collection component collects operating data at certain periods of time. The analysis component analyzes operating data for each indoor unit. The analyzed results display component visualizes and displays the analyzed data that has been analyzed by the analysis component.

Abstract: An operation information processing section (11) in a central remote controller (5) processes operation information from operation setting buttons (8a, 8b, 8c), each of which is independent in function, transmits the operation information through a transmission line (6), and generates screen information based on the operation information collected through the transmission line (6), and display the screen information on a display unit (9). A management information processing section (12a) generates screen information based on operation information of the air conditioners (1, 2) collected through the transmission line (6) and transmits the screen information to the remote monitor terminal (15) through a transmission line (13), and relays control information transmitted from the remote monitor terminal (15) through the transmission line (13), and transmits the control information to the air conditioners (1, 2) through the transmission line (6).

Abstract: Methods and apparatus for predicting the availability of hot water for showering and bathing. One or more parameters corresponding to the operation of a water heater are monitored over time. Data corresponding to the monitored parameters are processed to determine a rate at which hot water is being consumed by the shower/bath and/or other hot water consumers. Based on a hot water consumption rate and determination of a current hot water availability condition, a time at which the temperature of hot water supplied by the water heater is projected to fall below a minimum temperature threshold is determined. In one embodiment, the apparatus include a thermal-modeling computer and a control/monitor interface that is disposed in or proximate to a shower. In one embodiment, the thermal-modeling computer is installed at a water heater and data is transmitted between the thermal-modeling computer and the control/monitor interface via a wireless signal.

Abstract: An HVAC control system that accommodates and/or facilitates control from a remote location. The HVAC control system may include a web-enabled building control appliance with a controller, a first port and a second port. The controller may implement a web server that is coupled to the first port for serving up one or more web pages on a first network and for receiving a number of responses. The controller may also be coupled to the second port so as to communicate with one or more communicating thermostats via a second network. The web server may be adapted to provide one or more web-pages via the first port that solicit and accept an alarm condition for the one or more communicating thermostats. The controller may provide and/or monitor the alarm condition of the one or more communicating thermostats over the second network.

Abstract: A system for monitoring a remote refrigeration system includes a plurality of sensors that monitor parameters of components of the refrigeration system and a communication network that transfers signals generated by each of the plurality of sensors. A management center receives the signals from the communication network and processes the signals to determine an operating condition of at least one of the components. The management center generates an alarm based on the operating condition.

Abstract: Unheated external air is drawn into an electronic component housing (200). The external air is selectively heated to form heated air (209) and the extent of the heating is based at least in part upon the temperature within the electronic component housing (200). The heated air (209) or the unheated external air (206) is drawn across at least one electronic component (210) positioned within the electronic component housing (200). A first flow (222) of either the heated air or the unheated external air is selectively exhausted from the electronic component housing (200). A first amount of the first flow (222) is based at least in part upon the temperature within the electronic component housing. A second flow (216) of either the heated air or the unheated external air is selectively re-circulated within the housing. A second amount of the second flow (216) is based at least in part upon the temperature within the housing (200).

Abstract: The system includes a carbon dioxide sensor, a temperature sensor and a controller. The carbon dioxide sensor is in electrical communication with the controller and generates a carbon dioxide signal indicative of the carbon dioxide level contained in the air within the vehicle cabin. The temperature sensor is also in electrical communication with the controller and generates a temperature signal indicative of the temperature within the vehicle cabin. The controller is configured to initiate a safety precaution based on the carbon dioxide signal and the temperature signal.

Abstract: A real-time monitoring system that monitors various aspects of the operation of a refrigerant-cycle system is described. In one embodiment, the system includes a processor that measures power provided to the refrigerant-cycle system and that gathers data from one or more sensors and uses the sensor data to calculate a figure of merit related to the efficiency of the system. In one embodiment, the sensors include one or more of the following sensors: a suction line temperature sensor, a suction line pressure sensor, a suction line flow sensor, a hot gas line temperature sensor, a hot gas line pressure sensor, a hot gas line flow sensor, a liquid line temperature sensor, a liquid line pressure sensor, a liquid line flow sensor. In one embodiment, the sensors include one or more of an evaporator air temperature input sensor, an evaporator air temperature output sensor, an evaporator air flow sensor, an evaporator air humidity sensor, and a differential pressure sensor.

Abstract: An integrated controller for controlling a vapor compression based heating and cooling system. The integrated controller includes modules for independently controlling dry bulb temperature, humidity level, and incorporating a fault detection module therewith. The fault detection module being capable of detecting abnormal refrigerant levels using only temperature sensors on the condenser with thermal expansion valve or evaporator with fixed orifice type of expansion valve.

Abstract: A user adjustable visual display system and method for a digital thermostat having a backlit user display screen and system operation indicators is provided. The system allows a user to programmatically vary the illumination intensity of the backlit user display screen and the operational indicators. The variance provided includes disabling of the backlight and operational indicators. The system utilizes a variable pulse width modulated (PWM) intensity control for the backlight and indicators. Alternatively, an adjustable current drive illumination control is used to control the backlight and indicators. The selection of the desired intensity is provided via a display settings menu accessed via the user display screen.

Abstract: A temperature controller for controlling the temperature of an inside space that is serviced by one or more pieces of HVAC equipment. The temperature controller may include a controller having a control algorithm for controlling one or more pieces of HVAC equipment as well as a user interface that may be configured to display a hierarchical menu structure and to permit a user to traverse the menu structure. The user interface may be configured to display breadcrumbs that provide an indication to the user of the current location within a hierarchical menu structure, and in some cases, provide instructional information in a designated or common display area that helps instruct the user in using a particular menu or menu option. These and other features may help make the special purpose controller more intuitive to set up, program and operate.

Abstract: A zone thermostat for use in connection with an Electronically-Controlled Register vent (ECRV) that can be easily installed by a homeowner or general handyman is disclosed. The ECRV can be used to convert a non-zoned HVAC system into a zoned system. The ECRV can also be used in connection with a conventional zoned HVAC system to provide additional control and additional zones not provided by the conventional zoned HVAC system. In one embodiment, the ECRV is configured have a size and form-factor that conforms to a standard manually-controlled register vent. In one embodiment, the zone thermostat is configured to provide thermostat information to the ECRV. In one embodiment, the zone thermostat communicates with a central monitoring system that coordinates operation of the heating and cooling zones.

Abstract: The present invention comprises an intuitive algorithm embodiment. In said intuitive algorithm embodiment, a programmable thermostat that operates under control of a control program incorporating an intuitive algorithm. The intuitive algorithm allows a user to change the modes and setpoints of a programmable thermostat without need to refer to a display of currently effective operational modes, setpoints, or environmental sensor inputs. While a user may prefer to observe said display, the intuitive algorithm eliminates the need to do so.

Abstract: An innovative thermostat having a handicap access mode is described. When the handicap access mode is triggered, the thermostat accepts voice commands to control thermostat settings. This innovative thermostat is a particularly convenient feature for the visually impaired, and individuals with limited mobility. In one exemplary embodiment, the thermostat includes a controller operable in a direct input mode and/or a handicap access mode. When in the direct input mode, the controller receives user commands through mechanical actuation of an adjustment mechanism to adjust a thermostat setting. When in the handicap access mode the controller receives voice commands through a microphone to adjust a thermostat setting.

Abstract: A control system is provided for automatically setting up and controlling a climate control system for a building having one or more zones and one or more thermostats in communication with the associated heating or cooling components of the climate control system. In some embodiments, the climate control system comprises one or more heating or cooling systems which may be controlled by one or more thermostats. In other embodiments, the climate control system comprises a thermostat, a heating and cooling system, one or more remote temperature sensors corresponding to at least some of the one or more zones within the building, and one or more dampers corresponding to at least some of the one or more zones within the building.

Abstract: A thermostat designed to accommodate service graphics after sale by the manufacturer directly or indirectly to the installer for installation at the ultimate consumer's location. The thermostat housing has a compartment door that is appropriately sized to receive the service graphics of the installer. The installer purchases the thermostat with no graphics and at his option orders replacement doors with his personalized graphics imprinted, from the manufacturer or its agent, and replaces the original doors with the replacements before selling the thermostat to the ultimate consumer. The doors themselves are unique in that upon outward manual flexure of the door panel a pair of connectors tilt out of recesses in the housing permitting easy removal of the doors.

Abstract: A thermostat for controlling a climate control system is provided that comprises a network interface for establishing an Internet connection with a website of a remote service provider, and a microprocessor for controlling the operation of a climate control system. The microprocessor is in communication with the network interface for establishing an Internet connection and receiving user-specified information from a remote service provider that maintains a user-profile of information requested by the user. The thermostat further comprises a display device responsive to the microprocessor for displaying user-specified information received via the network controller from the remote service provider.

Abstract: An apparatus for diagnosing a cooling system includes a first sensor for sensing a first operating parameter, a second sensor for sensing a motor operating parameter, a controller in communication with the sensors for receiving a signal from each of the sensors, and a computer in communication with the controller. The computer includes a memory storing normal operating parameters for a plurality of cooling systems, and is operable to compare the first and motor operating parameters with the normal parameters of one of the plurality of cooling systems to diagnose the cooling system.

Abstract: An HVAC system controller which estimates the energy cost or savings incurred due to a user-instigated change in a climate control schedule. The HVAC system controller is adapted to operate a multi-zone climate control system in a building, and is especially adapted to operate a retrofit zone climate control system in a residence. The HVAC controller displays the estimated cost or savings to the homeowner, enabling him to make an informed decision about whether to keep the change in the climate control schedule.

Abstract: An appliance having an input device, a control, a motor, and an analog display is provided. The input device is employed to input a set point temperature. The control is operably coupled to the input device and receives the set point temperature from the input device. The motor is operably coupled to the control and receives instructions from the control based on the set point temperature. The analog display is operably coupled to the motor. The analog display is driven by the motor to temporarily display the set point temperature and then to display a current temperature as the current temperature increases toward the set point temperature.

Abstract: Between a characteristic a of a process chamber 21a having a large pressure loss and a characteristic b of a process chamber 21b having a small pressure loss, threshold value A (flow rate value Q3, pressure value P3) is set on the characteristic a. The threshold value A is set on a controller 9. When a rotation speed of a pump 3 is increased by an electric motor 8, the flow rate of a fluid flowing through pipelines 1, 2 and a flow path of a process chamber 21 increases. At the time, the flow rate of the fluid is measured by a flowmeter 4 and a pressure of the fluid is measured by a pressure switch 5. If the pressure reaches the pressure value P3 when the flow rate of the fluid reaches the flow rate value Q3, the pressure switch 5 operates. At the time, the controller 9 judges that the process chamber 21a having a large pressure loss is connected to the pipelines 1, 2.

Abstract: A graphical user interface system for a thermal comfort controller. The user interface system has a central processing unit coupled to a memory and a touch sensitive display unit. The memory stores a temperature schedule data structure and perhaps a temperature history data structure. The temperature schedule data structure is made up of at least one set-point. The temperature history data structure is made up of at least one Actual-Temperature-Point. The display presents the set-points and/or the Actual-Temperature-Points. One representation of the display is a graphical step-function. The user uses a finger or stylus to program the set-points by pointing and dragging a portion of the step-function.

Abstract: A real-time monitoring system that monitors various aspects of the operation of a refrigerant-cycle system is described. In one embodiment, the system includes a processor that measures power provided to the refrigerant-cycle system and that gathers data from one or more sensors and uses the sensor data to calculate a figure of merit related to the efficiency of the system. In one embodiment, the sensors include one or more of the following sensors: a suction line temperature sensor, a suction line pressure sensor, a suction line flow sensor, a hot gas line temperature sensor, a hot gas line pressure sensor, a hot gas line flow sensor, a liquid line temperature sensor, a liquid line pressure sensor, a liquid line flow sensor. In one embodiment, the sensors include one or more of an evaporator air temperature input sensor, an evaporator air temperature output sensor, an evaporator air flow sensor, an evaporator air humidity sensor, and a differential pressure sensor.

Abstract: An ambiance lighting system for a vehicular passenger compartment has a variable color light output which is automatically responsive to temperature changes. First and second light sources of different colors (e.g., blue and red) are positioned immediately behind the air discharge vents and are selectively energized by a control circuit so that the first light source radiates light through the vent when the temperature falls below a predetermined value and the second light sources energizes the second color of light when the air temperature rises above a predetermined value. Sensors are used to detect the temperature of air, preferably in the ducting plenum. Various control strategies can be deployed to achieve aesthetically interesting light presentations which enhance ambiance within the passenger compartment.