Pressure Relieve Valve On A/C Compressor, Checking

WARNING: This page is about a different car, the 2016 Volkswagen Beetle, 2015 Volkswagen Beetle, 2014 Volkswagen Beetle, 2013 Volkswagen Beetle, and 2012 Volkswagen Beetle. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: The pressure relief valve protects the entire refrigerant circuit against too high of pressure.

WARNING:

There is a danger of ice-up.

Check valve drains coolant when engine is running and pressure in coolant circuit is too high.

Turn the engine off.

Fig 1: Checking Pressure Relief Valve On A/C Compressor (Sanden)

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

The pressure relief valve -arrow- has operated when refrigerant oil is found in the close vicinity.
In this case, check the specified capacity for the refrigerant circuit.
Extract the refrigerant with the A/C Service Station VAS 6007A (or newer model) from the refrigerant circuit and fill it to the prescribed capacity again.

WARNING:

There is a danger of ice-up.

Check valve drains coolant when engine is running and pressure in coolant circuit is too high.

Turn the engine off.

Fig 2: Checking Check Valve On A/C Compressor (Denso)

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

The pressure relief valve -arrow- has operated when refrigerant oil is found in the close vicinity.
In this case, check the specified capacity for the refrigerant circuit.
Extract the refrigerant with the A/C Service Station VAS 6007A (or newer model) from the refrigerant circuit and fill it to the prescribed capacity again.