Abstract: A compression refrigeration system includes a switch to select between a plurality of operation modes of a metering device that controls a rate of flow of a refrigerant to an evaporator of the compression refrigeration system. Each operation mode is associated with a respective refrigerant. Further, the compression refrigeration system includes a reference database that comprises pressure-temperature data associated with a plurality of refrigerants. Furthermore, the compression refrigeration system includes a valve adjustment engine that is communicatively coupled to the switch and the reference database. The valve adjustment engine controls the metering device based on an operation mode of the metering device that is selected using the switch. The operation mode is selected based on a refrigerant with which the compression refrigeration system is currently charged.

Abstract: A compression refrigeration system includes a switch to select between a plurality of operation modes of a metering device that controls a rate of flow of a refrigerant to an evaporator of the compression refrigeration system. Each operation mode is associated with a respective refrigerant. Further, the compression refrigeration system includes a reference database that comprises pressure-temperature data associated with a plurality of refrigerants. Furthermore, the compression refrigeration system includes a valve adjustment engine that is communicatively coupled to the switch and the reference database. The valve adjustment engine controls the metering device based on an operation mode of the metering device that is selected using the switch. The operation mode is selected based on a refrigerant with which the compression refrigeration system is currently charged.

Abstract: An air mover system for use in an indoor unit of a heating, ventilation, and air conditioning (HVAC) system includes a blower comprising a motor and a blower control unit configured to control operations of the motor. The blower control unit includes a controller and a sensor communicably coupled to the controller. The sensor is configured to sense air inside the indoor unit and to provide sensor information to the controller. The controller is configured to determine whether a refrigerant is present in the air based on the sensor information and to control the blower to move the air out of the indoor unit in response to determining that the refrigerant is present in the air.

Abstract: A heat pump system including a charge compensator having a liquid line port for an inflow of a refrigerant into the charge compensator and for an outflow of the refrigerant from the charge compensator. The heat pump system further includes an isolation valve configured to control flows of the refrigerant to and from the charge compensator through a liquid line piping of the heat pump system based on whether the heat pump system is operating in a cooling mode, a defrost mode, or a heating mode, where the liquid line port is fluidly coupled to the liquid line piping of the heat pump system.

Abstract: A compression refrigeration system includes a switch to select between a plurality of operation modes of a metering device that controls a rate of flow of a refrigerant to an evaporator of the compression refrigeration system. Each operation mode is associated with a respective refrigerant. Further, the compression refrigeration system includes a reference database that comprises pressure-temperature data associated with a plurality of refrigerants. Furthermore, the compression refrigeration system includes a valve adjustment engine that is communicatively coupled to the switch and the reference database. The valve adjustment engine controls the metering device based on an operation mode of the metering device that is selected using the switch. The operation mode is selected based on a refrigerant with which the compression refrigeration system is currently charged.

Abstract: In one embodiment, an overflow sensor assembly of an HVAC unit includes a sensor mounting bracket that is configured to be coupled to a mounting surface of the HVAC unit such that sensor probes of the overflow sensor assembly are suspended within and extend into a condensate drain pan of the HVAC unit. The sensor probes are defined by a sensor element that is coupled to the sensor mounting bracket and a spring that is coupled to the sensor element. The sensor probes are configured to activate an overflow detection circuit when the sensor probes come in contact with condensate fluid collected in the condensate drain pan prior to the condensate fluid overflowing from the condensate drain pan.

Abstract: A method and apparatus for determining the sufficiency of refrigerant charge in an air conditioning system by the use of only two temperature measurements. The temperature of the liquid refrigerant leaving the condenser coil is sensed and the temperature of the condenser coil itself is sensed and the difference between these two measurements is calculated to provide an indication of the adequacy of refrigerant charge in the system. This process is refined by steps taken to eliminate measurements during transient operations and by filtering signals to eliminate undesirable noise. A permitted threshold of deviation is calculated by using probability theory.

Abstract: A method and apparatus for determining the sufficiency of the refrigerant charge in an air conditioning system by use of temperature measurements. The temperature of the liquid refrigerant leaving the condenser coil and the outdoor temperature are sensed and representative electrical signals are generated. The electrical signals are converted to digital values that are than compared to predetermined optimal values to determine whether the system is properly charged with refrigerant. An appropriate LED is lighted to indicate that the system is undercharged, overcharged or properly charged. For non-TXV/EXV systems a third parameter i.e. the return air wet bulb temperature is also sensed and a representative digital value thereof is included in the comparison with the predetermined known values to determine if the charge is proper.

Abstract: The sufficiency of refrigerant charge in an air conditioning system is determined by a comparison of two sensed temperatures in the system, one being the liquid line temperature and the other being either the outdoor temperature or the condenser coil temperature. In one embodiment the two sensed temperatures are displayed on respective thermochromic strips which are so calibrated and juxtaposed as to provide a visual indication, by the relative positions of the two displayed sensed temperatures, as to whether the refrigerant charge is adequate. In another embodiment, the sensed liquid line temperature is displayed by way of a plurality of LEDs and the other temperature is displayed by way of a marker on a temperature scale. If the two displayed temperatures are aligned, then the refrigerant charge is optimized, and if they are not aligned, the system is undercharged or overcharged.

Abstract: An air conditioning system includes a plurality of sensors for sensing temperature and/or pressure conditions of the system which collectively indicate the actual refrigerant charge level in the system. This level is then compared with optimum level values that are stored in memory, and the difference between the two is used to indicate whether the system is properly charged. If not, the difference is applied to open a charge valve or a purge valve to automatically install additional refrigerant or to remove refrigerant so as to establish an optimum volume of refrigerant in the system.

Abstract: A braze-free connector suitable for use in a refrigeration system that includes a connector body having a circular opening passing therethrough. The opening has a converging section that tapers downwardly from the entrance to the opening toward the back of the opening. A ferrule is slidably mounted upon a refrigerant tube which is inserted into the opening to place a tapered collapsible section of the ferrule in contact with the tapered section of the opening. The non-collapsible section of the ferrule is keyed to a nut which in turn is mated with a male thread formed on the connector body whereby the collapsible section of the ferrule is forced into engagement with the refrigerant tube. A pressure sensitive sealant is pre-coated upon at least the collapsible section of the ferrule which is activated as the ferrule is forced into engagement with the refrigerant tube.

Abstract: The refrigerant charge adequacy of an air conditioning system is determined by the sensing of two temperatures in the system, one being at a midpoint in a condenser coil and the other being the temperature in the liquid line of the condenser discharge, with the difference then being indicative of the degree of subcooling, which, in turn, may be indicative of refrigerant charge condition. The method is refined by measuring a third temperature at the compressor discharge, with the three temperature values then being used to calculate a pair of residual values which provide an indication of whether the two temperature approach is useful in determining charge adequacy under the existing conditions and if not, whether the system is overcharged or undercharged.

Abstract: A braze-free connector suitable for use in a refrigeration system that includes a connector body having a circular opening passing therethrough. The opening has a converging section that tapers downwardly from the entrance to the opening toward the back of the opening. A ferrule is slidably mounted upon a refrigerant tube which is inserted into the opening to place a tapered collapsible section of the ferrule in contact with the tapered section of the opening. The non-collapsible section of the ferrule is keyed to a nut which in turn is mated with a male thread formed on the connector body whereby the collapsible section of the ferrule is forced into engagement with the refrigerant tube. A pressure sensitive sealant is pre-coated upon at least the collapsible section of the ferrule which is activated as the ferrule is forced into engagement with the refrigerant tube.

Abstract: The refrigerant charge adequacy of an air conditioning system is determined by the sensing of two temperatures in the system, one being at a midpoint in a condenser coil and the other being the temperature in the liquid line of the condenser discharge, with the difference then being indicative of the degree of subcooling, which, in turn, may be indicative of refrigerant charge condition. The method is refined by measuring a third temperature at the compressor discharge, with the three temperature values then being used to calculate a pair of residual values which provide an indication of whether the two temperature approach is useful in determining charge adequacy under the existing conditions and if not, whether the system is overcharged or undercharged.

Abstract: In a residential furnace having a layered insulation material on the inner walls of the heat exchanger compartment, the inner aluminum foil layer has a plurality of holes formed therein in order to allow for the outer layer to absorb the sound within the heat exchanger compartment and thereby reduce the noise emanating from the furnace. Both the density and size of the holes are optimized to maximize the sound absorption performance over the particular frequency ranges that are characteristic of the furnace.

Abstract: A method and apparatus for determining the sufficiency of the refrigerant charge in an air conditioning system by use of temperature measurements. The temperature of the liquid refrigerant leaving the condenser coil and the outdoor temperature are sensed and representative electrical signals are generated. The electrical signals are converted to digital values that are than compared to predetermined optimal values to determine whether the system is properly charged with refrigerant. An appropriate LED is lighted to indicate that the system is undercharged, overcharged or properly charged. For non-TXV/EXV systems a third parameter i.e. the return air wet bulb temperature is also sensed and a representative digital value thereof is included in the comparison with the predetermined known values to determine if the charge is proper.

Abstract: The sufficiency of refrigerant charge in an air conditioning system is determined by a comparison of two sensed temperatures in the system, one being the liquid line temperature and the other being either the outdoor temperature or the condenser coil temperature. In one embodiment the two sensed temperatures are displayed on respective thermochromic strips which are so calibrated and juxtaposed as to provide a visual indication, by the relative positions of the two displayed sensed temperatures, as to whether the refrigerant charge is adequate. In another embodiment, the sensed liquid line temperature is displayed by way of a plurality of LEDs and the other temperature is displayed by way of a marker on a temperature scale. If the two displayed temperatures are aligned, then the refrigerant charge is optimized, and if they are not aligned, the system is undercharged or overcharged.

Abstract: A method and apparatus for determining the sufficiency of refrigerant charge in an air conditioning system by the use of only two temperature measurements. The temperature of the liquid refrigerant leaving the condenser coil is sensed and the temperature of the condenser coil itself is sensed and the difference between these two measurements is calculated to provide an indication of the adequacy of refrigerant charge in the system. This process is refined by steps taken to eliminate measurements during transient operations and by filtering signals to eliminate undesirable noise. A permitted threshold of deviation is calculated by using probability theory.

Abstract: A method and apparatus for determining the sufficiency of refrigerant charge in an air conditioning system using a single temperature sensor for sensing three different temperatures within the system to compute a condenser approach temperature difference, which in then compared with a predetermined optimal condenser approach temperature difference to indicate the charge condition of the system. The device includes an absorbent pad for sensing wet bulb temperatures, and is formed as a clamshell that can be clamped onto the condenser liquid line. A microprocessor is included to make the comparison and to appropriately display the result as a visual indication of charge adequacy.

Abstract: A braze-free connector for attaching a flow line to an operating unit of a flow system. The connector has a central passage into which the flow line is inserted through a tapered entranceway. The entranceway opens into a radially expanded cavity that surrounds a section of the flow line. The cavity is filled with a pressure activated adhesive. A ferrule is mounted in the entranceway and is rotatably mounted upon a threaded nut which mates with a male thread on the connector body. As the nut is advanced, the ferrule moves axially into the cavity to activate the adhesive, and at the same time, is forced radially into tight sealing contact with the flow line.