A preheater for a compressor that is capable of heating a lubricant oil efficiently with smaller power is provided. A preheater for a compressor includes: a capacitive oil surface sensor that is provided at a compressor used in a refrigerating cycle, and detects an oil surface of a lubricant oil A in the compressor; and a power supply unit that applies high-frequency voltage to the oil surface sensor.

There is disclosed an environmental control system for heating at least one enclosed space. The system comprises a heat-pump circuit that includes a compressor, a heat-output stage, an expansion device and an evaporator arranged in series along a flow path for a refrigerant. The heat-output stage comprises a primary heat exchanger and a secondary heat exchanger that are both configured to transfer heat from the refrigerant to one or more external mediums in thermal communication with the at least one enclosed space. The primary heat exchanger and the secondary heat exchanger are connected in series along the flow path, such that the secondary heat exchanger will transfer excess heat energy remaining within the refrigerant after passing through the primary heat exchanger to the one or more external mediums.

There is disclosed an environmental control system for heating at least one enclosed space. The system comprises a heat-pump circuit that includes a compressor, a heat-output stage, an expansion device and an evaporator arranged in series along a flow path for a refrigerant. The heat-output stage comprises a primary heat exchanger and a secondary heat exchanger that are both configured to transfer heat from the refrigerant to one or more external mediums in thermal communication with the at least one enclosed space. The primary heat exchanger and the secondary heat exchanger are connected in series along the flow path, such that the secondary heat exchanger will transfer excess heat energy remaining within the refrigerant after passing through the primary heat exchanger to the one or more external mediums.

The invention relates to a device and a method for icing prevention regulation for a heat pump evaporator (3) in air conditioning systems of vehicles, composed of a subsection (1) of a refrigerant circuit which can be operated both as a heat pump and also as an air conditioning system. The device comprises the heat pump evaporator (3), an electrical or mechanical refrigerant compressor (4), a cooler fan (9) which is attached to the heat pump evaporator (3) and which draws ambient air (11) upstream from and through the heat pump evaporator (3) at an adjustable flow speed, and which thus permits a permanent flow of ambient air (11) over the heat pump evaporator surface, a first temperature sensor (6) in or on the refrigerant line (5, 5a) upstream from the heat pump evaporator (3) with respect to the heat pump operating direction, and a control and regulating unit (8). The control and regulating unit (8) is connected via signal lines (10, 10a, 10b, 10c, 10e) at least to the first temperature sensor (6), to further sensors, in particular for detecting the ambient air temperature (Tu) and the vehicle speed (V.sub.F), to the expansion valve (2), to the cooler fan (9) and to the refrigerant compressor (4) for the direct or indirect regulation of the flow cross section of the expansion valve (2) and the rotational speed of the electric refrigerant compressor (4) or of the regulating valve of the mechanical refrigerant compressor (4) and for the actuation of the cooler fan (9) of the vehicle during heat pump operation.

The invention relates to a device and a method for icing prevention regulation for a heat pump evaporator (3) in air conditioning systems of vehicles, composed of a subsection (1) of a refrigerant circuit which can be operated both as a heat pump and also as an air conditioning system. The device comprises the heat pump evaporator (3), an electrical or mechanical refrigerant compressor (4), a cooler fan (9) which is attached to the heat pump evaporator (3) and which draws ambient air (11) upstream from and through the heat pump evaporator (3) at an adjustable flow speed, and which thus permits a permanent flow of ambient air (11) over the heat pump evaporator surface, a first temperature sensor (6) in or on the refrigerant line (5, 5a) upstream from the heat pump evaporator (3) with respect to the heat pump operating direction, and a control and regulating unit (8). The control and regulating unit (8) is connected via signal lines (10, 10a, 10b, 10c, 10e) at least to the first temperature sensor (6), to further sensors, in particular for detecting the ambient air temperature (Tu) and the vehicle speed (V.sub.F), to the expansion valve (2), to the cooler fan (9) and to the refrigerant compressor (4) for the direct or indirect regulation of the flow cross section of the expansion valve (2) and the rotational speed of the electric refrigerant compressor (4) or of the regulating valve of the mechanical refrigerant compressor (4) and for the actuation of the cooler fan (9) of the vehicle during heat pump operation.

An embodiment includes an air conditioner, including: a housing including an ambient side and an enclosure side, where the enclosure side faces an enclosure to be cooled by the air conditioner; the ambient side including an interface that fits in a flush-mounted configuration with respect to a wall of the enclosure to be cooled, whereby the entire air conditioner is disposed within the enclosure. Other embodiments are described and claimed.

An embodiment includes an air conditioner, including: a housing including an ambient side and an enclosure side, where the enclosure side faces an enclosure to be cooled by the air conditioner; the ambient side including an interface that fits in a flush-mounted configuration with respect to a wall of the enclosure to be cooled, whereby the entire air conditioner is disposed within the enclosure. Other embodiments are described and claimed.

A heat pump device can discharge air in a heat medium circuit regardless of the height positions of two bodies of the heat pump device and prevents refrigerant outflow when the refrigerant enters the heat medium circuit in the liquid heat exchanger. A pump causes the liquid heat medium to flow in a predetermined circulatory direction in a heat medium pipe, and a liquid heat exchanger, a first air vent valve and a second air vent valve are arranged in this order along a circulatory direction.

A system for providing air conditioning to a living space and heating potable water. The system comprising a heat pump circuit comprising a compressor for circulating a refrigerant around the heat pump circuit, a first condenser, a second condenser and an evaporator. The evaporator being adapted to receive a first flow of air from an air inlet to transfer heat from the first flow of air to the refrigerant. The first condenser being adapted to receive a flow of water to transfer heat from the refrigerant to the water. The second condenser being adapted to receive a second flow of air to transfer heat from the refrigerant to the second flow of air. The first flow being provided from the evaporator to a living space by an air outlet.

A preheater for a compressor that is capable of heating a lubricant oil efficiently with smaller power is provided. A preheater for a compressor includes: a capacitive oil surface sensor that is provided at a compressor used in a refrigerating cycle, and detects an oil surface of a lubricant oil A in the compressor; and a power supply unit that applies high-frequency voltage to the oil surface sensor.