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Detecting Leaks In The Refrigerant Circuit Using The UV Lamp Vas 6196/4

WARNING:

Do not look into UV lamp.

Do not direct UV lamp at other people.

NOTE:

The A/C system must run for at least 60 minutes so the additive distributes itself through the entire refrigerant circuit. The compressor must be running. Depending on the size of the leak, it may become visible within that time.

With leaks on evaporator, leak detection additive is possibly washed off with condensation and flows out via evaporator drain. Since the evaporator is not easily accessible on most vehicles, checking the evaporator drain may indicate if the evaporator is leaking. However, it is necessary for this purpose that leak detection additive has already been in the refrigerant circuit for a long period of time.

Protective goggles do not only serve as eye protection but also amplify the illumination of leak detection additive under UV light.

Depending on the accessibility of different components in the refrigerant circuit, it may be necessary to remove some vehicle components such as the bumper or air filter.

-- Move vehicle into a slightly darker area of the workshop (with daylight or bright lighting the effect of the UV light is diminished).

Fig 1: Checking For Refrigerant Leaks
GWWA87-0492Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Check the accessibility of the various components in the refrigerant circuit and remove any components in the area that block access to the refrigerant circuit such as noise insulation and the bumper.

-- Wear protective eyewear to protect the eyes.

-- Connect the UV-lamp to a 12 volt battery (vehicle battery). Observe correct polarity of connections.

-- Switch on UV lamp and illuminate components of refrigerant circuit. Locations where refrigerant, refrigerant oil and leak detection additive has leaked out light up under fluorescent UV light.

NOTE:

The leak detection additive can remain in the refrigerant circuit.