Refrigerant Pressure Sensor / Switch: Description and Operation

The refrigerant pressure sensor (B12) measures the refrigerant pressure and relays it to the pushbutton control module.

Switching off the A/C compressor
The refrigerant pressure sensor transfers the current value to the pushbutton control module. When the following values are present the A/C compressor is switched off by the pushbutton control module:
- Refrigerant pressure < 2 bar = A/C compressor off
- Refrigerant pressure > 28 bar = A/C compressor off

Switching on the auxiliary fan
The pressure measured by the refrigerant pressure sensor is also compared with a value stored in the pushbutton control module. When the following values are present the fan is adjusted infinitely:
- Refrigerant pressure > 16 bar = fan low speed
- Refrigerant pressure > 20 bar = fan maximum speed