P83.40-A001-79
Refrigerant circuit (schematic) |
1 | Refrigerant compressor | 7 | Heat exchanger (in hybrid and electric vehicles) | |
2 | Condenser | 8 | Expansion valve (in hybrid and electric vehicles) | |
3 | Accumulator (drier) | A | High pressure, gaseous | |
4 | Evaporator | B | High pressure, liquid | |
5 | Inner heat exchanger | C | Low pressure, liquid | |
6 | Expansion valve or valve unit (equipment-specific) | D | Low pressure, gaseous |
The condenser is either water-cooled (electric vehicles) or air-cooled depending on the equipment installed in the vehicle. Thermal or electric expansion valves are installed depending on equipment.
Model all (CAR)
with code 582 (Rear air conditioner)
A second evaporator circuit is also present.
Overview
This document contains information on:
General
Function requirements
Function of the refrigerant circuit
High-pressure side
Low-pressure side
General
In the refrigerant circuit, the pressures and the physical states of the refrigerant change. It absorbs heat and releases it again elsewhere. The refrigerant circuit is regulated via the climate control controller.
The refrigerant circuit consists of a low-pressure side and a high-pressure side, which are separated, depending on equipment, by one or more valves and by the refrigerant compressor.
The refrigerant circuit can be filled with the synthetic refrigerants R134a or R1234yf.
Function requirements
Climate control switched on
Refrigerant compressor switched on (A/C function)
Function of the refrigerant circuit
The individual components of the refrigerant circuit are interconnected through hoses and pipelines and form a closed system. The refrigerant circuit essentially consists of the following components:
High-pressure side
The refrigerant compressor draws in the gaseous refrigerant from the evaporator, compresses it and routes it into the condenser. The compressed, hot coolant is cooled there by the passing airstream or by the coolant depending on the equipment installed.
Due to the cooling, the gaseous refrigerant changes its physical state and liquefies. The liquid refrigerant then flows through the drier. The drier draws moisture from the refrigerant, separates out vapor locks and filters out mechanical impurities.
After the drier, the refrigerant reaches the expansion valve, where it sprays into the evaporator under high pressure.
Low-pressure side
In the evaporator, the refrigerant decompresses and changes its physical state from liquid to gas. The refrigerant takes the heat it requires for evaporation from the passing airstream, which is cooled in the process. The refrigerant compressor draws in the now gaseous refrigerant and compresses it.