volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

Leak detection in refrigerant circuit using compressed air or nitrogen > < Draining air conditioner service station
Detecting leaks in refrigerant circuit
Detecting leaks in refrigerant circuit
  Note
t  Different processes are described in this workshop manual for leak detection in the refrigerant circuit. These processes have been tested and lead to a positive result under the different conditions of use if the application is carried out correctly and in accordance with the complaint.
t  When leak detection using compressed air/nitrogen or vacuum does not produce results, use electronic leak detector or UV leak detector additive.
t  Small leaks can be detected with, for example, an electronic leak detector or a UV leak detector lamp.
t  A wide range of processes are offered on the open market for finding leaks in refrigerant circuits. These processes do not always produce conclusive results. If they are not used precisely according to the specifications, they may even cause components of the refrigerant circuit to develop leaks where they had none before. Furthermore, certain processes can cause preliminary or permanent damage to the components of the refrigerant circuit
t  Components that are found to be leaking must not be repaired. They have to be replaced with genuine parts.
t  A leaking refrigerant circuit must not be charged with refrigerant, therefore evacuate an empty refrigerant circuit and check for leaks before charging the system with refrigerant → Chapter.
  Caution
t  If there is evidence to suggest that chemical substances have been added in the vehicle to seal leaks, do not connect the air conditioner service station and do not extract the refrigerant.
t  Chemical substances used to seal leaks form deposits in the refrigerant circuit. These can impair the function of the air conditioning system and cause the air conditioning system (and your air conditioner service station) to fail.
t  Make your customer aware of the fact that there are substances in his/her air conditioning system that do not have VW approval. This air conditioning system cannot be drained or repaired by you.
  Note
t  Volkswagen rejects the use of chemical substances for purposes of sealing leaks in refrigerant circuits.
t  Chemical substances used for sealing leaks in refrigerant circuits often react with the surrounding air and the humidity contained within. They cause deposits to build up in the refrigerant circuit (and your air conditioner service station), valves to malfunction and defects in other components with which they come into contact. These deposits cannot be completely removed from the components (not even by purging).
t  It is often not possible to detect from the outside whether chemical substances have been used to seal leaks in the refrigerant circuit. The adhesive label that serves to identify its use can usually not be found. Therefore, exercise caution when working on vehicles for which you have no service or repair record.
t  Containers or tanks are offered as accessories on the open market that are designed to separate these chemical substances (to seal leaks). Since Volkswagen rejects the use of these substances, no statement can be made at this point regarding the effectiveness and separation rate of these filters.
   

Leak detection in refrigerant circuit using compressed air or nitrogen > < Draining air conditioner service station