A/C System Performance Check

A/C Refrigerant System (R-134a) Pressures And Temperatures, Checking

The pressures and temperatures in the A/C system will vary depending on Engine Speed (RPM), coolant fan speed, engine temperature, whether A/C clutch is engaged or not, outside temperature, humidity, etc.

N�v=Pressure/Temperature Chart:

The pressure and temperature specifications given on the chart are based on the following:
- Engine Speed (RPM) at 1500
- fresh air blower on high speed
- A/C switch adjusted to Max. cooling





1 - Evaporator
2 - Low pressure service valve
3 - Compressor, low pressure side
4 - Compressor, high pressure side
5 - Condenser
6 - Receiver drier
7 - Sight glass
8 - High pressure service valve
9 - Expansion valve