An apparatus for heating water has a tank for storing water and an air conditioning system that defines a refrigerant flow path through which refrigerant flows. The refrigerant flow path passes through the heat exchanger so that refrigerant heat is contributed to the tank. A control system controls operation of the water heating apparatus.

According to another aspect, the present disclosure relates to a system for modular adiabatic evaporative pre-cooling of a horizontal air-cooled commercial refrigeration condenser. The system includes an evaporative media with an air permeable construction. The evaporative media has a water absorbable construction. The system also has a water supply port for supplying the volume of water. The system also has a water distributer for distributing the volume of water supplied from the water supply port. The water distributer distributes the volume of water to the evaporative media. The system also includes a water drain port for draining the volume of water distributed to the evaporative media.

A motor for a rotary compressor, and a compressor and an air conditioner having the motor, are disclosed. The motor includes a stator core and a rotor core. The stator core has a through-hole in a center thereof. The stator core is provided with a plurality of circumferentially spaced stator teeth, and the number of stator teeth is M. The rotor core is rotatably disposed in the through-hole. The rotor core is provided with a plurality of circumferentially spaced rotor slots, and the number of the rotor slots is N, wherein 2≤N−M≤6. A cross-sectional area of the stator core is denoted as S, and a distance between two endpoints of two radially opposite curved segments of an outer edge of the cross section is denoted as L, wherein 0.93≤4*S/3.14/L2≤0.96.

A free cooling system includes a plurality of free cooling outdoor units each including a heat medium circuit, a controller, and a communication unit, the heat medium circuit being configured by connecting a heat medium pump, a first heat exchanger, and a heat source side of a second heat exchanger by pipes, a heat medium circulating in the heat medium circuit, the controller configured to control the heat medium pump, and the communication units performing communication with each other, wherein the plurality of free cooling outdoor units are coupled with each other by a load pipe that allows a load heat medium to flow to or flow out from a load side of each second heat exchanger.

A heat transfer system that includes one or more heat exchangers and one or more control pumps that control flow through the heat exchangers. In order to source a variable load, the control pumps can be controlled to operate at less than full duty flow. In an example embodiment, a controller can calculate, when each heat exchanger is clean, coefficient values of each respective heat exchanger. The controller can determine, during real-time operation, real-time coefficient values of the heat exchanger to compare with the respective coefficient values when clean, in order to determine whether there is fouling in that heat exchanger. In some examples, the controller can determine that maintenance is required on the heat exchanger due to the fouling, and perform flushing of the heat exchanger by operating one or more of the control pumps at full duty load during real-time operation to source the variable load.

A heating, ventilation, and/or air conditioning (HVAC) unit includes a refrigerant circuit including a reheat coil and a condenser system, a first valve disposed along the refrigerant circuit and configured to modulate refrigerant flow to the reheat coil and to the condenser system, and a second valve disposed along the refrigerant circuit downstream of the first valve relative to a direction of the refrigerant flow through the refrigerant circuit. The condenser system includes a first condenser coil and a second condenser coil, and the second valve is configured to be actuated to control refrigerant flow to the second condenser coil.

A heating, ventilation, and/or air conditioning (HVAC) system has a refrigerant circuit that includes a compressor, a condenser system with a first set of tubes and a second set of tubes fluidly separate from the first set of tubes within the condenser system, and a valve positioned downstream of the compressor and upstream of the second set of tubes relative to a direction of refrigerant flow through the refrigerant circuit, in which the refrigerant circuit is configured to direct refrigerant through the first set of tubes and through the second set of tubes. The HVAC system further has a switch configured to detect an operating parameter and to instruct the valve to close based on the operating parameter such that refrigerant flow is blocked through the second set of tubes and refrigerant flow is enabled through the first set of tubes.

A CO2 refrigeration system can include a condenser, multiple fans, and a controller. The condenser can be configured to cool CO2 and the multiple fans can be configured to affect cooling operations of the condenser. The controller may be configured to obtain a temperature value of CO2 output by the condenser. The controller may be configured to determine if the condenser is operating properly using the temperature value of the CO2. The controller may be configured to obtain values of input current and input voltage provided to the multiple fans. The controller can determine a number of in-operational or faulty fans of the multiple fans using, at least in part, the values of the input current and the input voltage and a model that relates input current to input voltage for known numbers of in-operational or faulty fans.

A heating, ventilation, and/or air conditioning (HVAC) system includes a condenser section and a plurality of panels configured to abut one another in a common plane to form a divider panel assembly. Each panel of the plurality of panels is sequentially insertable into and removable from the condenser section.

An air conditioner according to an embodiment includes: a compressor configured to compress a refrigerant; an indoor heat exchanger configured to convert a vapor refrigerant into a liquid refrigerant in a heating mode; an outdoor heat exchanger configured to convert a liquid refrigerant into a vapor refrigerant in the heating mode; a main pipe connecting the indoor heat exchanger to the outdoor heat exchanger; an injection pipe branching from the main pipe and connecting to an injection port of the compressor; an injection valve installed on the injection pipe and configured to control a flux of the refrigerant flowing to the injection pipe; and a controller configured to calculate a target discharge superheat (DSH) based on a correlation between a compression coefficient, a compressor frequency, and a DSH that are represented by an operating condition , and control a current DSH based on the target DSH.