A heating, ventilation, and/or air conditioning (HVAC) system includes a sensor configured to detect an operating parameter of the HVAC system, a processor, and a memory having instructions executable by the processor to cause the processor, during a normal operation mode of the HVAC system, to iteratively receive feedback from the sensor indicative of a value of the operating parameter, compare the value with reference data, and determine a refrigerant charge level of the HVAC system based on the value and the reference data.

A heat source system includes heat source apparatuses each with refrigerant circuit and water heat exchanger. A water supply header pipe merges and supplies, to a load, water flowing in from the heat exchangers. A water return header pipe splits, into the heat exchangers, water flowing in from the load. Pumps feed water to the heat exchangers. A bypass pipe with bypass valve connects the supply and return header pipes. A differential pressure gauge measures a water pressure difference between supply and return. A controller determines the number of heat source apparatuses to operate, from heat generated by refrigerant circuits and heat required, determines whether an operating frequency of the pump connected to a heat source apparatus to be operated is a minimum frequency, and controls the pump operating frequency and/or an opening degree of the bypass valve such that the water pressure difference falls within a target range.

A compressor driving device includes a three-phase alternating current power supply input end, a relay module, a rectifier circuit, and a driving control circuit which are sequentially connected; the rectifier circuit is used for converting connected alternating current into direct current and then outputting the direct current to a direct current bus; the driving control circuit is used for converting the direct current output by the direct current bus into compressor driving power; a pressure switch is used for measuring the pressure value in a refrigerating system, and when the measured pressure value is larger than a preset pressure threshold, disconnecting the power supply circuit of the relay module; the driving control circuit is also used for detecting the on-off state of the pressure switch and controlling the compressor to stop working when the pressure switch is switched off.

A system configured to modify an environmental condition of a building includes a valve configured to regulate a flow of a fluid and an actuator. The actuator includes a motor and a drive coupling, the drive coupling driven by the motor and coupled to the valve for driving the valve between multiple positions. The system further includes a flow rate sensor configured to measure the flow rate of the fluid through the valve and a processing circuit coupled to the motor and the flow rate sensor. The processing circuit is configured to receive a flow rate setpoint and a flow rate measurement, determine an actuator position setpoint based on the flow rate setpoint and the flow rate measurement, and operate the motor to drive the drive coupling to the actuator position setpoint. The flow rate sensor and the processing circuit are located within a common integrated device chassis.

A controller for an energy plant includes a processing circuit having a processor and memory which stores instructions executed by the processor. The processing circuit is configured to identify, from a plurality of thermodynamic states affected by a plurality of heat, ventilation, and air conditioning (HVAC) devices, a reduced subset of the plurality of thermodynamic states to be predicted based on connections between the plurality of HVAC devices. The processing circuit is configured to predict values of the reduced subset of the plurality of thermodynamic states and operate the plurality of HVAC devices based on the predicted values of the reduced subset of the plurality of thermodynamic states.

Disclosed herein are air conditioning systems comprising a refrigerant line configured to transport a refrigerant; a compressor in fluid communication with the suction line; and a controller in communication with a sensor configured to measure a characteristic of the refrigerant line. The compressor can be configured to move the refrigerant through the refrigerant line, and the refrigerant can have a first temperature at the outlet of the compressor. The controller configured to receive sensor data from the sensor indicative of a current value associated with the characteristic of the refrigerant line; determine, based at least partially on the sensor data, that the characteristic of the refrigerant line is above a predetermined threshold; and output instructions for the compressor to perform one or more corrective actions.

A controller of an HVAC system monitors a suction-side property and a liquid-side property over a period of time. The controller determines whether the suction-side property has an increasing or decreasing trend over the period of time. The controller determines whether the liquid-side property has an increasing or decreasing trend. In response to determining that both the suction-side property and the liquid-side property have an increasing trend over the period of time, a fan fault is detected. In response to determining that the suction-side property has a decreasing trend and the liquid-side property has an increasing trend over the period of time, a blockage of a refrigerant conduit subsystem is detected. In response to determining that both the suction-side property and the liquid-side property have a decreasing trend over the period of time, a blower fault is detected.

A refrigerant control system includes: a charge module configured to determine an amount of refrigerant that is present within a first portion of a refrigeration system within a building; and an isolation module configured to selectively open and close an isolation valve of the refrigeration system and to, via the isolation valve, maintain the amount of refrigerant within the first portion within the building below a predetermined amount of the refrigerant.

An air-conditioning device includes: a heat medium cycle circuit including: a pump, a plurality of indoor heat exchangers, and a plurality of flow control devices configured to control a flow rate of the heat medium through the heat medium cycle circuit; a heat-source-side device configured to heat or cool the heat medium; and a controller that includes a determination processing unit to determine whether the heat medium is caused to pass through the plurality of indoor heat exchangers where heat exchange is stopped, a selection processing unit to select, based on a determination from the determination processing unit, an indoor heat exchanger through which the heat medium is caused to pass from the plurality of indoor heat exchangers where heat exchange is stopped, and an instruction processing unit to instruct a release of a flow control device that corresponds to the indoor heat exchanger selected.

A method for detecting power consumption of a multi-split air conditioner includes acquiring hydraulic device data of a heat recovery multi-split air conditioner and determining a hydraulic device heat absorption value based on the hydraulic device data. The method includes acquiring outdoor unit data, indoor unit data, and power consumption data of the heat recovery multi-split air conditioner; determining a condenser heating capacity and an evaporator cooling capacity based on the outdoor unit data, the indoor unit data, and the hydraulic device data; and determining indoor unit power consumption and hydraulic device power consumption based on the hydraulic device heat absorption value, the power consumption data, the condenser heating capacity, and the evaporator cooling capacity.