Carrier Corporation

Electric Power Research Institute Incorporated

Kevin F Dudley

Kevin Bryant Dunshee

Lowell E Paige

Peter G Pierret

Deborah A Champagne

John F Hannon

Robert P Dolan

Thomas R Phillips

Roger J Voorhis

Alan D Abbott

Daniel L Waser

Zhichao Guo

Kevin A Kimberly

Paul Stoddard

Breet A Desmaraid

A control device having a graphical user interface for controlling the operation of a transport refrigeration unit is disclosed. The graphical user interface may include a menu structure having multiple levels of menu options, executable functions and data items that may be navigated and viewed by a user. Access to the various menus may be user-specific and controlled so that a subset of the information in the menu structure is available to normal users, and larger subsets of the information are available to advanced users having higher levels of authorization to the menus and information contained in the graphical user interface device. The graphical user interface may also include programmable soft keys that may take users directly to frequently viewed menu options, functions and data items without the necessity of navigating through the levels of the menu structure.

Programmable customized user interface for transport refrigeration units

A regenerative source of heat is provided for the oil used to lubricate a compressor within a heating, cooling or refrigeration system. The regenerative source absorbs heat from the oil when it is circulating through the compressor at a relatively high temperature. The regenerative source gives up heat to the oil following deactivation of the compressor. The source of heat includes a thermal phase change material that is preferably a hydrated salt capable of storing sufficient thermal energy to maintain the oil above any temperatures that would cause damage to the moving parts of the compressor.

Compressor heat regenerative system

A data collection system allows occupants in one or more locations to provide indications as to their respective levels of comfort. The indications as to comfort level are preferably provided through personal computers in these locations. Each computer is programmed to display a menu of comfort level options that may be selected by the user of the computer. Each computer is operative to require that any selected comfort level be accompanied by a verification as to the user making the one or more selections. The verification preferably requires an entry of an identification that may be checked against a stored identification. Each computer is operative to timely provide the selections as to comfort level by a recognized user to a network computer. The network computer is operative to analyze the comfort level information from these computers and send one or more commands to an HVAC system providing conditioned air to the locations.

Limited access comfort control

Two liquid levels are sensed in the oil sump of a compressor to determine if sufficient oil and excess refrigerant are present prior to starting the compressor and appropriate steps taken, if necessary. At start-up, and during operation, the presence or flow of liquid refrigerant in the suction of the compressor is sensed and appropriate steps taken, if necessary.

Compressor protection from liquid hazards

A system and method allows occupants in various locations to provide indications as to their respective levels of comfort. The indications as to comfort level are provided to a network computer. The network computer is operative to compute overall levels of comfort for each location by using a weighting factor for that location in combination with the indications as to levels of comfort These overall levels of comfort are sent to an HVAC control for further analysis prior to controlling the HVAC system that is to provide conditioned air to the locations. The resulting control of the HVAC system is influenced by the over weighting or under weighting factors used in computing the comfort levels for the locations.

Location adjusted HVAC control

A computer is operative to analyze comfort level information from one or more locations to be provided with conditioned air. The computer determines whether the comfort level information indicates that a particular overall level of comfort is being repetitively requested by a location over an extended period of time. The computer is operative to send a warning signal when this occurs.

HVAC system monitoring

A method of load shedding wherein a series of load shedding thermostats are mounted in building serviced by a utility. Each thermostat contains an addressable processor arranged to receive different code inputs form the utility. Heat loss and load characteristics for buildings are calculated from measured indoor and outdoor temperature movements along with the equipment's duty cycle for a given period of time and the required setback temperature for a given coded input is set into the thermostat based upon heat loss and load characteristics of the building.

Load shedding thermostat

A method of ensuring adequate oil thickness for the bearings in a sealed compressor includes the step of monitoring the viscosity of a lubricant for the bearings. If the monitored viscosity drops below a minimum, then some control is effected to reduce the necessary bearing film thickness. In a preferred embodiment, an unloader valve is opened to reduce the load on the bearings.

Method of ensuring optimum viscosity to compressor bearing system

A defrost control for a heat pump system initiates a defrost when certain computed conditions are exceeded. The conditions include a limit as to the difference that may be permitted between the maximum temperature difference of two measured temperatures and the current difference of these measured temperatures. The two measured temperatures are the temperature of the indoor coil of the heat pump and the indoor air temperature of the air being heated by the indoor coil.

Defrost control for heat pump

Apparatus and method for controlling an air distribution system of the type which includes a motor drivingly associated with a blower and a duct system, and further including a target air flow rate signal which represents a target air flow for the air distribution system. The apparatus and method provide control of the motor speed to maintain a rate of air flow in the system at substantially the target air flow rate regardless of the status pressure therein. The apparatus provides a speed signal representative of the speed of the motor, and a control signal in response to the target air flow rate signal and the speed signal, and controls the motor speed in response to the control signal. The central signal is provided independent of the duct system. Motor speed is controlled by applying a voltage to the motor which varies in accordance with the control signal for maintaining the rate of air flow in the system at substantially the target air flow rate regardless of the static pressure therein. The control signal is provided by implementing a constant air flow control algorithm which is responsive to both the target air flow rate signal and the speed signal.

Airflow control for variable speed blowers

According to the present invention a damper for controlling the flow of conditioned air supplied through a supply duct to a conditioned space is provided. The damper includes a support housing which defines a flow passage which communicates the supply duct with the conditioned space. A plurality of damper blades are mounted within the support housing for pivotal movement about respective spaced apart parallel axes. A blade link interconnects the damper blades in a ganged relation so that a common pivoted orientation of the damper blades is determined by the position of the blade link. Means are provided for selectively exerting a force on the blade link which will either move the link toward the second position to increase the flow of air through the damper or for exerting a force on the blade link to move the link toward the first position to decrease the flow of air through the damper. Means are provided which allows the blade link to move toward the second position (maximum flow) in response to a force imparted on the damper blades by a build-up of pressure in the supply duct. Under such circumstances the force imparted upon the damper blades is sufficient to overcome the force exerted on the blade link to move the link toward said first position (flow substantially blocked).

Powered damper having automatic static duct pressure relief

An integrated heat pump and hot water system provides heating or cooling of a comfort zone, as required, and also provides water heating. As a power management feature, the speed of a variable speed compressor is reduced to a predetermined fraction, e.g. 80%, of its normal operating speed, in response to a demand limit signal provided from the electric power utility during times of peak electrical load. A reference compressor speed is computed based on the current compressor speed, indoor temperature, outdoor temperature, and zero-load temperature difference. If the system is between operating cycles when the demand limit signal is received, a stored speed is used which corresponds to the compressor speed at a predetermined outdoor-indoor temperature difference. This system produces graceful reduction in comfort cooling during demand limit periods.

Electric power demand limit for variable speed heat pumps and integrated

In an integrated heat pump and water heating system with a variable speed compressor drive, a variable speed indoor fan, and an expansion valve with a variable duty cycle the indoor fan speed is controlled as a function of a space heating load, and the compressor speed is controlled as a function of outdoor temperature and space heating load.

Control of space heating and water heating using variable speed heat pump

During start up of a heat pump compressor that is controlled by a pulsed expansion valve system the discharge temperature sensor control of the pulse system is interrupted and a predetermined constant pulse is applied to the expansion valve increasing capacity and reducing loss of suction pressure resulting in improved cyclic system efficiency. The constant pulse control is applied only during start up until the discharge temperature reaches a predetermined level at which point control is returned to the discharge temperature sensor.

Method and apparatus for improving efficiency of a pulsed expansion

A heat pump diagnostic and control system for controlling indoor coil freeze-up when in the cooling mode is provided. A low indoor coil temperature is sensed, the indoor fan speed is increased in steps up to a maximum to thaw the frost on the indoor coil. If this is not sufficient, the compressor speed is then reduced in steps until it is turned off and if necessary, it is held off until such time as the temperature sensor indicates thawing of the indoor coil of the heat exchanger. Diagnostic flow chart and control circuitry for accomplishing this control are disclosed.

Growing community of inventors

Cazenovia, NY, United States of America

Kevin F Dudley