Abstract: A method and system for detecting and diagnosing faults in a heating, ventilation and air conditioning (HVAC) system includes a remote server receiving data from sensors associated with the HVAC system. The data received includes measured sensor data, from both HVAC equipment and co-located sensors, and identifying criteria for identifying the piece of equipment associated with the sensor and/or identifying a location of the sensor, which may or may not be on or in the HVAC equipment. A probability that a fault exists and/or a likelihood of occurrence of a fault in one of the pieces of the equipment is calculated based on the data received, and an alert is generated in accordance with an analysis thereof, which may include comparison of the probability and/or likelihood with predetermined threshold(s).

Abstract: Systems and methods of operating a heating, ventilation, and/or air conditioning (HVAC) system are disclosed that may include starting a timer substantially concurrently with the HVAC system, entering a cooling cycle, and preventing a multi-speed blower in the HVAC system from changing speeds until the timer expires.

Abstract: An HVAC system has a plurality of humidity sensors and a controller configured to selectively control which of the plurality of humidity sensors affects operation of the HVAC system. A method of controlling humidity includes providing a plurality of humidity sensors, assigning one of the plurality of humidity sensors as a humidity priority sensor, and affecting a humidity in response to feedback from the humidity priority sensor. A system controller for an HVAC system has an interface configured to present a plurality of humidity sensors and the system controller is configured to allow a user to select which of the plurality of humidity sensors affects operation of the HVAC system.

Abstract: A system and method is provided for monitoring a system pressure to infer whether a high pressure cut out (HPCO) switch has opened disabling a heating, ventilating, and air conditioning (HVAC) compressor. A system and method are also provided for determining whether to disable the HVAC compressor based on a status of a low pressure cut out (LPCO) switch, an ambient temperature, and system mode state. The systems and methods may be used interchangeably with the appropriate adjustments to decision limits, such as where the LPCO may be monitored to infer status and the HPCO status may be directly used with temperature and system mode state.

Abstract: A user interface for a control system for an air conditioning apparatus includes a visual display and keys for scrolling menu items and entering commands to the control system. The interface is mounted in the apparatus cabinet and on a rotatable bracket to orient the interface for ease of reading the display and actuating the respective keys.

Abstract: An air conditioning (HVAC) system for a residential dwelling or other building with enclosed spaces includes multiple thermostats hard wire interconnected or communicating via radio frequency transceivers. The thermostats each include control circuits for adjusting the setpoint temperature at any one thermostat and displaying the set temperature at all thermostats, setting the time at any one thermostat and displaying the time at all thermostats, controlling the thermostat temperature setting from a selected one of the thermostats and providing a setpoint for control of the air conditioning system based on an average temperature sensed by all of the thermostats. A method for correctly setting a thermostat time display to one of Daylight Saving Time or Standard Time and displaying an icon identifying one or the other is disclosed.

Abstract: A system and method is provided for monitoring a system pressure to infer whether a high pressure cut out (HPCO) switch has opened disabling a heating, ventilating, and air conditioning (HVAC) compressor. A system and method are also provided for determining whether to disable the HVAC compressor based on a status of a low pressure cut out (LPCO) switch, an ambient temperature, and system mode state. The systems and methods may be used interchangeably with the appropriate adjustments to decision limits, such as where the LPCO may be monitored to infer status and the HPCO status may be directly used with temperature and system mode state.

Abstract: An HVAC system includes a variable speed electric motor driven fan for circulating air to an enclosed space through an indoor unit for providing heating or cooling effect to air circulated through the indoor unit. A controller with user or system installer actuatable switches includes a programmable microcontroller providing a pulse width modulated (PWM) signal to a motor control unit to select a predetermined air flowrate less than full air flowrate during system startup and shutdown. User input parameters include selected percentages of full air flowrate to satisfy requirements for reduced noise level, lower humidity and for improved sensible heating of air being circulated, the latter being effective particularly for heat pump applications. Selection of pre-run, short run and shutdown cycles may be provided.

Abstract: An air conditioning (HVAC) system for a residential dwelling or other building with enclosed spaces includes multiple thermostats hard wire interconnected or communicating via radio frequency transceivers. The thermostats each include control circuits for adjusting the setpoint temperature at any one thermostat and displaying the set temperature at all thermostats, setting the time at any one thermostat and displaying the time at all thermostats, controlling the thermostat temperature setting from a selected one of the thermostats and providing a setpoint for control of the air conditioning system based on an average temperature sensed by all of the thermostats. A method for correctly setting a thermostat time display to one of Daylight Saving Time or Standard Time and displaying an icon identifying one or the other is disclosed.

Abstract: An air conditioning (HVAC) system for a residential dwelling or other building with enclosed spaces includes multiple thermostats hard wire interconnected or communicating via radio frequency transceivers. The thermostats each include control circuits for adjusting the setpoint temperature at any one thermostat and displaying the set temperature at all thermostats, setting the time at any one thermostat and displaying the time at all thermostats, controlling the thermostat temperature setting from a selected one of the thermostats and providing a setpoint for control of the air conditioning system based on an average temperature sensed by all of the thermostats. A method for correctly setting a thermostat time display to one of Daylight Saving Time or Standard Time and displaying an icon identifying one or the other is disclosed.

Abstract: A user interface for a control system for an air conditioning apparatus includes a visual display and keys for scrolling menu items and entering commands to the control system. The interface is mounted in the apparatus cabinet and on a rotatable bracket to orient the interface for ease of reading the display and actuating the respective keys.

Abstract: An air conditioning system thermostat includes a visual display and plural switch actuators, respectively backlit by an electroluminescent lamp and LED light sources mounted on a circuit board disposed in a thermostat housing. A control circuit causes at least one switch actuator to be illuminated continuously and the light sources for the display and the remaining switch actuators are illuminated in response to actuation of any one of the switch actuators. Switch contact elements mounted on the switch actuators and the circuit board provide advantageous positioning of the LED light sources for the switch actuators. An energy savings switch actuator allows the control circuit to directly assume setback temperature settings in response to a first actuation and a second actuation resets the thermostat to the initial user set temperature settings.

Abstract: An HVAC controller including a first input; a second input; first means, responsive to a first signal received on the first input, for generating a first mode of operation; second means, responsive to a second signal received on the second input, for generating a second mode of operation; and third means, responsive to a third signal received substantially simultaneously on the first and second inputs, for generating a third mode of operation.