Abstract: A heat pump includes a refrigerant loop. The refrigerant loop includes a compressor, a first region of a first heat exchanger, a first branching point, a first shutoff valve, a second shutoff valve, and a second heat exchanger. The compressor includes a low-pressure inlet, a mid-pressure inlet, and an outlet. The first heat exchanger is positioned immediately downstream of the outlet of the compressor. The first branching point is positioned immediately downstream of the first region of the first heat exchanger. The refrigerant loop splits into a first path and a second path at the first branching point. The first shutoff valve is positioned along the first path and immediately downstream of the first branching point. The second shutoff valve is positioned along the second path and immediately downstream of the first branching point. The second heat exchanger is downstream of the first heat exchanger.

Abstract: A heat pump includes a refrigerant loop. The refrigerant loop includes a compressor, a first region of a first heat exchanger, a first branching point, a first shutoff valve, a second shutoff valve, and a second heat exchanger. The compressor includes a low-pressure inlet, a mid-pressure inlet, and an outlet. The first heat exchanger is positioned immediately downstream of the outlet of the compressor. The first branching point is positioned immediately downstream of the first region of the first heat exchanger. The refrigerant loop splits into a first path and a second path at the first branching point. The first shutoff valve is positioned along the first path and immediately downstream of the first branching point. The second shutoff valve is positioned along the second path and immediately downstream of the first branching point. The second heat exchanger is downstream of the first heat exchanger.

Abstract: A heat pump includes a refrigerant loop. The refrigerant loop can include a compressor, a first region of a first heat exchanger, a second heat exchanger, and a bypass branch. The compressor includes a low-pressure inlet, a mid-pressure inlet, and an outlet. The first heat exchanger is positioned downstream of the outlet of the compressor. The second heat exchanger is positioned downstream of the first heat exchanger. The bypass branch includes an entrance and an exit. The entrance to the bypass branch is positioned downstream of the outlet of the compressor and upstream of the first region of the first heat exchanger. The exit of the bypass branch is positioned upstream of the second heat exchanger.

Abstract: A vehicle climate control system includes a heat exchanger to heat ambient air using engine waste heat, and a plurality of positive temperature coefficient (PTC) heating elements to heat air passed through the heat exchanger. The vehicle also includes a controller programmed to, while the vehicle is driven without engine propulsion, issue a command to sequentially de-energize the PTC heating elements before an upcoming engine activation. The sequential de-energization of the PTC heating elements is performed according to a schedule that is based upon a power surge dissipation time.

Abstract: A vehicle includes an engine cooling system. The engine cooling system includes an engine. A radiator is fluidly coupled to the engine. A sensor is configured to provide a temperature reading of a coolant at the engine. The vehicle further includes a heat pump system. The heat pump system includes a condenser disposed proximate the radiator and fluidly coupled to the compressor. An evaporator is fluidly coupled to the condenser. A climate fan is fluidly coupled to an exterior surface of the evaporator. A climate control module is configured to control a speed of the climate fan. The climate control module establishes a maximum speed of the climate fan in response to a temperature reading from the sensor.

Abstract: Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Abstract: Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Abstract: A vehicle cooling system may include a variable displacement compressor, and a controller configured to, in response to a determination that the compressor is operating within a gurgling zone that is defined by a predefined range of compressor speeds and currents, generate a current signal defining a displacement for the compressor based on a speed of the compressor and an ambient temperature to control the displacement to reduce refrigerant flow noise.

Abstract: A vehicle climate control system includes a heat exchanger to heat ambient air using engine waste heat, and a plurality of positive temperature coefficient (PTC) heating elements to heat air passed through the heat exchanger. The vehicle also includes a controller programmed to, while the vehicle is driven without engine propulsion, issue a command to sequentially de-energize the PTC heating elements before an upcoming engine activation. The sequential de-energization of the PTC heating elements is performed according to a schedule that is based upon a power surge dissipation time.

Abstract: A hybrid electric vehicle (HEV) that includes an internal combustion engine and a climate control system (CCS) coupled to controllers configured to auto start-stop the engine when the HEV decelerates to an engine-stop threshold speed. The controllers are also configured to adjust a climate-fan-speed by a predetermined initial-factor, and at subsequent timed-intervals with a speed-factor that is adjusted from the initial-factor at each timed-interval, such that engine restart is inhibited by perceptually small speed adjustments and perceptually slow timed-interval cabin cooling adjustments. Such gradual adjustments are tuned to increase passenger perceptions of continuing cabin comfort, which reduce the likelihood that a passenger may adjust the CCS to require engine restart, and to increase auto stop-start fuel economy.

Abstract: Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Abstract: Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Abstract: Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Abstract: A hybrid electric vehicle (HEV) that includes an internal combustion engine and a climate control system (CCS) coupled to controllers configured to auto start-stop the engine when the HEV decelerates to an engine-stop threshold speed. The controllers are also configured to adjust a climate-fan-speed by a predetermined initial-factor, and at subsequent timed-intervals with a speed-factor that is adjusted from the initial-factor at each timed-interval, such that engine restart is inhibited by perceptually small speed adjustments and perceptually slow timed-interval cabin cooling adjustments. Such gradual adjustments are tuned to increase passenger perceptions of continuing cabin comfort, which reduce the likelihood that a passenger may adjust the CCS to require engine restart, and to increase auto stop-start fuel economy.

Abstract: A method of controlling power to a vehicle accessory gradually shuts down power to the vehicle accessory and gradually restores power to the vehicle accessory. After a request for an auto-shutdown of an internal combustion engine of a vehicle is detected, power to the vehicle accessory is reduced on a predetermined schedule responsive to such detection. The occurrence of a restart of the internal combustion engine of a vehicle is determined, and power supplied to the vehicle accessory is increased on a predetermined schedule responsive to the restart.

Abstract: A vehicle climate control system includes a heat exchanger to heat ambient air using engine waste heat, and a plurality of positive temperature coefficient (PTC) heating elements to heat air passed through the heat exchanger. The vehicle also includes a controller programmed to, while the vehicle is driven without engine propulsion, issue a command to sequentially de-energize the PTC heating elements before an upcoming engine activation. The sequential de-energization of the PTC heating elements is performed according to a schedule that is based upon a power surge dissipation time.

Abstract: Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Abstract: Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Abstract: Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Abstract: A vehicle cooling system may include a variable displacement compressor, and a controller configured to, in response to a determination that the compressor is operating within a gurgling zone that is defined by a predefined range of compressor speeds and currents, generate a current signal defining a displacement for the compressor based on a speed of the compressor and an ambient temperature to control the displacement to reduce refrigerant flow noise.