A system may be operable to circulate a working fluid between first and second heat exchangers. The system may include a suction line, a low-side compressor, a high-side compressor and a discharge line. The low-side and high-side compressors may both be in fluid communication with the suction and discharge lines.

A compressor may include a shell containing a motor, a compression mechanism and a lubricant sump. The compressor may also include first and second temperature sensors, and a control module. The first temperature sensor may be at least partially disposed within the lubricant sump and may measure a first temperature of a lubricant at a first position. The second temperature sensor may be at least partially disposed within the lubricant sump and may measure a second temperature of the lubricant at a second position that is vertically higher than the first position. The control module is in communication with the first and second temperature sensors. The control module may determine a first difference between the first temperature and the second temperature. The control module may determine whether a liquid level of the lubricant in the lubricant sump is below a predetermined level based on the first difference.

An oil balancing system for a multiple compressor system is provided. The oil balancing system includes an oil equalization line disposed between a first compressor and a second compressor. A first solenoid valve is provided in the oil equalization line. A first signal corresponds to a first oil level in the first compressor. A second signal corresponds to a second oil level in the second compressor. An oil balancing module uses the first signal and the second signal to diagnose an oil imbalance between the first compressor and the second compressor, and applies corrective action, whereby the corrective action includes sending control signals to operate at least one of the first compressor, the second compressor, or the first solenoid valve in a way that eliminates the oil imbalance.

A compression device includes a first compressor and a second compressor mounted in parallel, each compressor including a leakproof enclosure including a low pressure portion containing a motor and an oil sump, an oil level equalization conduit putting into communication the oil sumps of the first and second compressors, and control means adapted for controlling the starting and the stopping of the first and second compressors. The first compressor includes first detection means coupled with the control means and adapted for detecting an oil level in the oil sump of the first compressor. The control means are adapted for controlling the stopping of the second compressor when the oil level detected by the first detection means falls below a first predetermined value.

A compressor-oil-receiving apparatus for a compressor system filled with a compressor oil for transfer into the compressor system. The apparatus includes a housing which forms a receiving volume for the compressor oil, and an oil filler neck with a filling opening on a side, which is directed away from the receiving volume and with an outlet opening on a side which is directed toward the receiving volume, wherein the oil filler neck forms a housing opening for filling of the receiving volume with the compressor oil, and the outlet opening is arranged such that, through filling of the receiving volume, an air volume enclosed by the housing, and the compressor oil that has been introduced is formed in the receiving volume.

A climate control system includes a compressor which includes a compressor housing, a compressor element provided in the compressor housing, a lubricant circuit, and an auxiliary sump. The lubricant circuit includes a lubricant sump provided in the compressor housing. The auxiliary sump is in fluid communication with the lubricant sump. A method for maintaining lubrication supply for a compressor of a climate control system includes transferring lubricant from the auxiliary sump to the lubricant sump of the compressor when a height of the lubricant in the auxiliary sump is greater than a height in the lubricant sump and returning the lubricant from the lubricant sump to the auxiliary sump when a height of the lubricant in the lubricant sump is higher than a height of a predetermined minimum level in the lubricant sump. The lubricant in the auxiliary sump and lubricant sump are equalized by gravity.

A compressor-oil-receiving apparatus for a compressor system filled with a compressor oil for transfer into the compressor system. The apparatus includes a housing which forms a receiving volume for the compressor oil, and an oil filler neck with a filling opening on a side, which is directed away from the receiving volume and with an outlet opening on a side which is directed toward the receiving volume, wherein the oil filler neck forms a housing opening for filling of the receiving volume with the compressor oil, and the outlet opening is arranged such that, through filling of the receiving volume, an air volume enclosed by the housing, and the compressor oil that has been introduced is formed in the receiving volume.

A pump system, method of manufacturing same, and vehicle includes: a housing with a pump and an electric motor; a pump inlet; a pump outlet; and a drive shaft driven by the motor, for driving the pump to pressurize fluid. An intermediate housing wall is positioned between the pump and motor, covers a motor cavity, and has a return port. An auxiliary circuit directs a portion of fluid flow to the motor cavity. A fill level control plate is positioned between the wall and the motor cavity, forming an overflow region therebetween, and includes an overflow opening for flow from the motor cavity to the overflow region. The plate causes a liquid level within the motor cavity to rise and a return path directs fluid through the overflow opening in the plate and relatively down the overflow region, to return back to the pump via the return port.