A monitoring system for a heating, ventilation, and air conditioning (HVAC) system of a building includes a monitoring device installed at the building, a monitoring server located remotely from the building, and a review server. The monitoring device measures an aggregate current supplied to components of the HVAC system and transmits current data based on the measured aggregate current. The monitoring server receives the transmitted current data and, based on the received current data, assesses whether failures have occurred in first and second components of the HVAC components. The monitoring server generates a first advisory in response to determining that the failure has occurred in the first component. The review server provides the first advisory to a technician for review and, in response to the technician verifying that the failure has occurred, transmits a first alert.

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Hvac system remote monitoring and diagnosis

Salt hydrates as latent heat storage materials:Thermophysical properties and costs

A monitoring system for a heating, ventilation, and air conditioning (HVAC) system of a residence includes a monitoring device installed at the residence and a server located remotely from the residence. The monitoring device measures an aggregate current supplied to a plurality of components of the HVAC system and transmits current data based on the measured aggregate current. The server receives the transmitted current data and, based on the received current, assesses whether a failure has occurred in a first component of the plurality of components of the HVAC system and assesses whether a failure has occurred in a second component of the plurality of components of the HVAC system.

Residential solutions hvac monitoring and diagnosis

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. In one embodiment, the sensors include one or more of a condenser air temperature input sensor, a condenser air temperature output sensor, and a condenser air flow sensor, an evaporator air humidity sensor. In one embodiment, the sensors include one or more of an ambient air sensor and an ambient humidity sensor.

Air filter monitoring system

A cooling control system comprises a cooling apparatus having a refrigerant compressor, a vapor condenser, an expansion valve, an evaporator and a blower, a first temperature detection device for detecting a room temperature, a second temperature detection device for detecting a temperature of the refrigerant which is introduced into the evaporator, a detection device for detecting a temperature difference between a temperature of the refrigerant discharged from the evaporator and the temperature of the refrigerant introduced into the evaporator, and a control device for controlling operations of the compressor as well as the blower and for controlling an opening of the expansion valve in response to the detected inflowing refrigerant temperature, the detected temperature difference and the detected room temperature.

Cooling control system and expansion valve therefor

In a refrigeration cycle in which the opening of the expansion valve is controlled by the super-heat degree of the refrigerant periodically detected at the outlet of the evaporator, a negative control signal is produced to rapidly change the opening of the expansion valve when the detected super-heat degree has reached zero. As a result, occurrence of the liquid back is prevented.

Refrigerant flow control device

The present invention provides an air conditioning apparatus for automobiles equipped with a heat exchanger and a control method for the apparatus, by which the heat transfer area of the heat exchanger can be properly controlled to permit a stable cycle operation, even when the capacity of a condenser is relatively overly enhanced under a condition of the low atmospheric temperature. The apparatus and the control method are achieved with such an arrangement that either one or both of headers of a heat exchanger is provided with at least one refrigerant flow rate control valve capable of opening and closing refrigerant passages in each header, the heat exchanger has a refrigerant inlet provided in one header and a refrigerant outlet provided in the other header, and the control valve is opened and closed to change the number of the passages allowing the refrigerant to pass therethrough, for thereby changing the effective heat transfer area for heat exchange dependent on the atmospheric temperature.

Air conditioning apparatus, heat exchanger for use in the apparatus and apparatus control method

A refrigerant flow rate measuring apparatus has a means for detecting the opening degree A of an expansion valve of a refrigeration cycle, a pressure detecting means for detecting the refrigerant pressure Pi at upstream side of the expansion valve, a pressure detecting means for detecting the refrigerant pressure Po at downstream side of the expansion valve, a refrigerant density detecting means for detecting the density γi of the refrigerant at the inlet side of the expansion valve, a converting means for directly or indirectly converting the values detected by the detecting means into electric signals, and a calculating means for calculating the flow rate of the refrigerant in accordance with the following formula, from the electric signals. ##EQU1##

Apparatus for measuring refrigerant flow rate in refrigeration cycle

The present invention relates to a heat storage material for air conditioning or for waste heat recovery, principally containing magnesium chloride hexahydrate which is doped as a nucleator with synthetic zeolite, magnesium silicate, sodium metasilicate, sodium silicate, calcium silicate, alumina, silicic anhydride, silicon carbide, calcium carbonate, or/and calcium fluoride, whereby the heat storage material can be effectively used over a long period of time.

Heat storage material

An automobile air conditioner has a refrigeration cycle composed of a compressor, condenser, liquid tank, orifice means and an evaporator, as well as mechanical parts such as a radiator and radiator fan associated with the condenser and a blower combined with the evaporator. The compressor is operatively connected to the automobile engine through a connecting means so as to be driven by the engine selectively in accordance with the temperature in the passenger's compartment. According to the invention, the compressor is driven when the automobile is being braked, even if the temperature in the compartment is lower than a set temperature, to make an efficient use of the kinetic energy possessed by the mass of the automobile. The cold energy generated during braking is suitably stored and is released into the passenger's compartment as desired.

Seigo Miyamoto

Papers

Refrigerant flow control device

Air conditioning apparatus, heat exchanger for use in the apparatus and apparatus control method

Apparatus for measuring refrigerant flow rate in refrigeration cycle

Heat storage material

Air conditioner for automobiles