A method of heating a component within a heating, ventilation and air conditioning (HVAC) system is provided. The method includes maintaining a non-heating condition of the HVAC system component when the HVAC system component is in a non-operational state. The method also includes determining when the HVAC system component will switch from the non-operational state to an operational state, the determination based on a threshold parameter being met. The method further includes operating a heating device from the non-heating condition to a heating condition to heat the HVAC system component from a temperature to a target temperature suitable for the operational state of the HVAC system component.

A refrigerant pipe attachment structure is provided, in which it can be ensured that a refrigerant pipe is held and thermal resistance between the refrigerant pipe and a heat transfer member can be sufficiently reduced. A heat transfer member formed with an elongated groove into which a refrigerant pipe is fitted and thermally contacting a cooling target is provided. An elastic member formed in an elongated plate shape extending along an extension direction of the refrigerant pipe and including a pipe-facing part facing the refrigerant pipe is provided. A pressing mechanism configured to press the elastic member toward the heat transfer member is provided.

A heat-recovery-type refrigerating apparatus includes a compressor, a heat-source-side heat exchanger, and a plurality of usage-side heat exchangers, and refrigerant is sent from the usage-side heat exchanger functioning as a refrigerant radiator to the usage-side heat exchanger functioning as a refrigerant evaporator, whereby heat can be recovered between the usage-side heat exchangers. Here, a portion of the heat-source-side heat exchanger is configured as a precooling heat exchanger for always circulating high-pressure vapor refrigerant discharged from the compressor, and a refrigerant cooler for cooling an electrical equipment item is connected to a downstream side of the precooling heat exchanger.

The present disclosure relates to an air conditioner and a compressor. The compressor includes: a first cylinder assembly, including a first cylinder body and a first sliding vane, a volume control assembly, including a pressure regulator; wherein the pressure regulator is provided with a storage cavity, and the storage cavity is communicated with the variable volume control cavity; wherein the first sliding vane is configured to slide in a reciprocating manner between the first compression cavity and the variable volume control cavity along the first sliding vane groove, to change the volume of the variable volume control cavity; and the refrigerant introduced into the variable volume control cavity flows between the variable volume control cavity and the storage cavity along with a change of the volume of the variable volume control cavity.

The present disclosure relates to an air conditioner and a compressor. The compressor includes: a first cylinder assembly, including a first cylinder body and a first sliding vane, a volume control assembly, including a pressure regulator; wherein the pressure regulator is provided with a storage cavity, and the storage cavity is communicated with the variable volume control cavity; wherein the first sliding vane is configured to slide in a reciprocating manner between the first compression cavity and the variable volume control cavity along the first sliding vane groove, to change the volume of the variable volume control cavity; and the refrigerant introduced into the variable volume control cavity flows between the variable volume control cavity and the storage cavity along with a change of the volume of the variable volume control cavity.

Examples of an electrically powered transport refrigeration unit (TRU) are disclosed. In one example, the TRU may include a refrigeration circuit that includes an electrically powered compressor, an evaporator equipped with an electrically powered blower, and a gas cooler equipped with an electrically powered blower. The TRU may also include a control circuit and a power regulator unit. The power regulator unit may be configured to supply variable DC and/or AC outputs to power components of the refrigeration circuit, and the control circuit may be configured to regulate the variable DC and AC outputs of the power regulator unit so as to control the operation of the TRU. The electrically powered TRU may be configured to use R774 as refrigerant.

An oil separator includes a capturing member inside a main body container, which includes a first capturing member portion arranged on a side closer to an inflow pipe and a second capturing member portion being arranged on a side closer to an outflow pipe and having a porosity smaller than that of the first capturing member portion. Therefore, a driving force is generated by the capturing member having the different porosities. Through the driving force, a force of gravity, and a capillary phenomenon, oil inside the main body container is transported to an oil return pipe to prevent re-scattering of the oil, thereby being capable of suppressing reduction in oil separation efficiency. At the same time, oil return efficiency to the compressor is improved.

The present disclosure relates to a method for controlling a level of superheat during a pump mode of operation of a refrigeration system, wherein the refrigeration system can operate in either the pump mode or a compressor mode, and has an electronically controlled expansion valve (EEV). A controller obtains a stored, predetermined pump differential pressure range able to be produced by a pump of the system. The controller also obtains a stored, predetermined superheat range, and detects a superheat level. When the detected superheat level is outside of the superheat temperature range, the controller commands adjusting at least one of the EEV and a speed of the pump based on whether the detected superheat level is above or below the superheat range, and whether a current pump differential pressure is above or below the predetermined pump differential pressure range.

The present disclosure relates to a method for controlling a level of superheat during a pump mode of operation of a refrigeration system, wherein the refrigeration system can operate in either the pump mode or a compressor mode, and has an electronically controlled expansion valve (EEV). A controller obtains a stored, predetermined pump differential pressure range able to be produced by a pump of the system. The controller also obtains a stored, predetermined superheat range, and detects a superheat level. When the detected superheat level is outside of the superheat temperature range, the controller commands adjusting at least one of the EEV and a speed of the pump based on whether the detected superheat level is above or below the superheat range, and whether a current pump differential pressure is above or below the predetermined pump differential pressure range.

In one aspect, a refrigeration system is provided. The refrigeration system includes a compressor coupled to a variable frequency drive (VFD), a condenser, an evaporator, an oil separator, and an oil conditioning circuit. The oil conditioning circuit is thermally coupled to the VFD and configured to heat oil from the oil separator with heat produced by the VFD.