What should be the touch temperature of the suction line connected to the compressor?

The suction line connected to the compressor should feel cool to the touch under normal operating conditions. This is because the suction line transports low-pressure refrigerant gas back to the compressor after it has absorbed heat from the indoor environment. During this process, the refrigerant evaporates and takes on heat, reducing its temperature.

When the suction line feels cool, it indicates that the refrigerant is effectively absorbing heat from the space being cooled, ensuring efficient system operation. If the line were hot or even warm, it could suggest issues such as insufficient refrigerant levels or problems with the compressor itself, indicating that heat is not being adequately removed from the system. The cool temperature indicates the refrigerant is performing its function properly, involving proper evaporation and heat exchange, which is crucial for the air conditioning system's performance.